part 2 - english

Emirate of Abu DhabiMunicipalities & Agricultural Dept.

Health & Safety Codes of Practice

forConstruction Projects

SiteStandards & Guidelines

for Consultants & Contractors

Foreword

Table of Contents

Definitions and Contact Details

PRELIMINARIES

SITE TRANSPORT, PLANT & EQUIPMENT

SITE TOOLS & MACHINERY

LIFTING OPERATIONS

CONSTRUCTION OPERATIONS

WORKING AT HEIGHT

SPECIAL PROCESSES

Document No. Revision Date Section title (i)

ADM/H&S/Pt 2 01 March 2005 Foreword 1 of 1

Municipalities & Agricultural Department

H&S Construction Codes of Practice

PART TWO

Foreword

In an industry such as ours with its diversity of activities, personal injury and health risks are,

unfortunately, an ever present hazard.

To successfully combat these hazards it is important that all of us contribute to the health and safety of

ourselves and others in all our work activities.

This H&S Construction Codes of Practice (Part Two) is intended to provide a base at which the

highest level of safety can be achieved on all our construction projects. It provides not only for the

physical working environment, but for appropriate consultation and discussion between the

department, consultants and contractors on accident prevention and occupational Health & Safety

matters;

Although the standards and guidelines contained in this manual have been developed from the best

and most appropriate international health and safety standards, they are not intended to replace any

present, or future Ministerial Orders applicable to health and safety of persons at work, nor any

specific health and safety requirements incorporated in contract specifications, all of which should be

fully adhered to at all times.

All concerned should note that as these manuals are controlled documents and as such, various forms

and checklists contained in them are sample formats only and should not be removed. A master file of

all the forms checklists and drawings are held with ADM Health and Safety Unit, copies of which are

readily available on request by quoting the Document No. located in the footers.

Both manuals will be regularly reviewed by ADM’s H&S Committee, and any amendments or additions

made by that committee, will be circulated to all concerned.

I look forward to the full co-operation of all concerned in, over a period of time, adopting the standards

and guidelines laid down in this manual, and to work together to achieve an improved safety record for

this very important industry.

Signed:

Undersecretary of Municipalities & Agricultural Department

Document No. Revision Date Section title (ii)

ADM/H&S/Pt 2 01 March 2005 Table of Contents 1 of 2



PART TWO

TABLE OF CONTENTS - PART TWO

FOREWORD

(i) Foreword

TABLE OF CONTENTS

(ii) Table of Contents

DEFINITIONS & CONTACT DETAILS

(iii) Definition of terms used in Part Two

(iv) Municipalities & Agricultural Dept. Abu Dhabi Municipality H&S Contact Details +

Emergency Contacts

PRELIMINARIES

1.0 ENVIRONMENTAL PROTECTION

2.0 WORKING IN HIGH TEMPERATURES AND REMOTE LOCATIONS

3.0 NOISE AT WORK

4.0 OCCUPATIONAL HEALTH

5.0 SUBSTANCES HAZARDOUS TO HEALTH

6.0 OVERHEAD AND UNDERGROUND SERVICES

7.0 ELECTRICITY AT WORK

8.0 MANUAL HANDLING & LIFTING

9.0 HIGHLY FLAMMABLE LIQUIDS & LIQUEFIED PETROLEUM GASES

10.0 SAFETY SIGNAGE

11.0 PERMIT TO WORK

12.0 PERSONAL PROTECTIVE EQUIPMENT (P.P.E)

SITE TRANSPORT, PLANT & EQUIPMENT

13.0 SITE TRANSPORT

14.0 MOBILE PLANT & EQUIPMENT

15.0 STATIC PLANT AND EQUIPMENT

TABLE OF CONTENTS - PART TWO continued

Document No. Revision Date Section title (ii)

ADM/H&S/Pt 2 01 March 2005 Table of Contents 2 of 2



PART TWO

SITE TOOLS & MACHINERY

16.0 PORTABLE TOOLS

17.0 ABRASIVE WHEELS

18.0 WOODWORKING MACHINERY

LIFTING OPERATIONS

19.0 CRANES AND HOISTS

20.0 LIFTING GEAR

CONSTRUCTION OPERATIONS

21.0 CONFINED SPACES

22.0 ROAD WORKS - BRIDGES

23.0 EXCAVATIONS - COFFERDAMS

24.0 TUNELLING - SHAFT SINKING

25.0 FALSEWORK

26.0 PILING

27.0 WELDING

28.0 WORKING OVER OR ADJACENT TO WATER

WORKING AT HEIGHT

29.0 SCAFFOLDING – LADDERS – CRADLES – SAFETY NETS

30.0 ERECTION OF STRUCTURES

31.0 DEMOLITION

32.0 SAFE WORKING ON ROOFS

33.0 REFURBISHMENT

34.0 MAINTENANCE

SPECIAL PROCESSES

35.0 � High Pressure Water Jetting

� Lasers

� Site Investigation

� Watercraft & Dredging

� Diving



PART TWO

Document No. Revision Date Section title (iii)

ADM/H&S/Pt 2 01 March 2005 Definition of Terms used in Part 2 1 of 1

Definition of terms used in Part Two

H&S Health and Safety

ADM Municipalities & Agricultural Dept. Abu Dhabi Municipality

Consultant Company appointed by the Owner/Client for all

Design/Management aspects of Project

Contractor Main Contractor appointed by the Owner/Client for the

Construction of the Project

Sub Contractor Company appointed by the Contractor, Owner or Client to

carry out designated aspects of the Project

Health & Safety Plan Format used by the Consultant to identify the main H&S risks

during the design stage of a contract

Lifting Appliances

A grab, winch, pulley block, gin wheel, hoist, crane,

excavator, dragline.

Lifting Gear

A chain, sling, rope sling, webbing sling or similar gear and a

ring, link, hook, shackle, swivel or eyebolt.

SWL Safe Working Load.

ASLI Automatic Safe Load Indicator.

Scaffold Any temporarily provided structure on or from which persons

perform work in connection with operations or works to which

this manual applies.

Site Any place where building operations or works of engineering

construction, or both such operations of such works are

being carried on, and any temporary storage or workshop

area associated with the works.

Sloping Roof A roof with a pitch of more than 10 degrees.

CE mark Recognised mark for personal protective equipment tested

and approved to international standards.

ADWEA. Abu Dhabi Water and Electricity Authority

RCCB Residual Current Circuit Breakers

mA milli Amp

SECTION 1

SECTION 1

ENVIRONMENTAL PROTECTION

DEFINITION 1

INTRODUCTION

MAIN APPLICABLE U.A.E. LEGISLATION

MAIN APPLICABLE BEST PRACTICE AND TECHNICAL GUIDELINES

EXECUTIVE REGULATIONS AND LOCAL ORDERS

1.1 GENERAL 2

1.2 ENVIRONMENTAL ASSESSMENT –

IDENTIFYING POTENTIAL IMPACTS ON THE ENVIRONMENT 3

1.3 ENVIRONMENTAL MANAGEMENT AND MINIMISATION OF IMPACTS 3

1.4 ENVIRONMENTAL MONITORING AND ONGOING INSPECTIONS 4

1.5 THE FEDERAL LAW ON PROTECTION AND DEVELOPMENT OF THE 5

ENVIRONMENT (1999)


Health & Safety at Work

PART TWO

Document No. Revision Date Section title 1

ADM/H&S/Pt 2 01 March 2005 ENVIRONMENTAL PROTECTION 1 of 6

SECTION 1


DEFINITION

The key issues that must be taken into consideration when undertaking any work which may, to any

extent, impact the environment.

INTRODUCTION

During construction certain development projects pose a significant risk to the environment. This risk

must be addressed through the consideration of Environmental Protection which involves

environmental assessment, management and monitoring to ensure that the effects of development

are not significantly detrimental. All personnel are responsible for considering the environmental

implications of their activities. This should be overseen by the consultant, or a specialist

environmental consultant where appropriate. Construction practices that fail to control pollution can

cause damage to the terrestrial environment, upset ecological systems and wildlife communities, and

result in the contamination of land and groundwater.

The issue of environmental protection during the contract period should be discussed with the

consultant prior to the site hand-over. Where deemed appropriate the consultant should seek

guidance from an approved specialist environmental consultant. Stiff penalties can be brought to bear

upon individual persons and companies whose actions result in damage, be it temporary or

permanent, direct or indirect, to the environment.


Federal Law No. 24 (1999) on Protection and Development of the Environment

Ministerial Order No.32 (1982) regarding protection of employers against occupational hazards

Local orders on discharge and disposal of wastes (Environmental Protection Section - Food and

Environmental Control Centre - Abu Dhabi Municipality)



PART TWO




ERWDA (2003).Technical Guidance Document (TG-0003R)

Standards and Limits for:

A. Pollution to Air and Marine Environments.

B. Occupational Exposure.

C. Pesticides and Chemical Use. Draft July 6 2003.

ERWDA (2003). Technical Guidance Document

Development of Construction Environmental Management (CEMP) - Onshore. Draft November 2003.


The contractor should contact the Environmental Protection Section of the Food and Environmental

Control Centre of Abu Dhabi Municipality to ascertain what standards and/or regulations are currently

in force.

1.1 GENERAL

• all contracts, whether new or existing, must comply with the Federal law and enforcing

regulations on environmental protection and also any local orders currently in place.

• it is recommended that all contracts, whether new or existing, comply with best practice

and technical guidance.

• in accordance with best practice recommendations, the contractor must have in place/be in

the process of developing an integrated Health, Safety Environmental Management

System in order to minimise risks.

• the contractor should make himself aware of any risks to the environment which may occur

within or outside the agreed site area as a result of his activities.

• the contractor should seek advice from an approved specialist environmental consultant as

to what measures should be taken to prevent or reduce to an acceptable level (as agreed

by the local authorities) the impact on the environment of activities taking place under the

contract in question.

• the contractor should have procedures in place to enable the monitoring of all discharges

into the environment, be they liquid, solid or gaseous and ensure adherence to permissible

threshold emission levels. Scrutiny of data arising from environmental monitoring may be

undertaken by the relevant authorities.



PART TWO



1.2 ENVIRONMENTAL ASSESSMENT-

IDENTIFYING POTENTIAL IMPACTS ON THE ENVIRONMENT

In order the have a full appreciation of the all potential environmental implications of a project,

the consultant must be familiar with all details any previous environmental studies,

conducted/instructed by Abu Dhabi Municipality. This should include the identification of all

direct and indirect impacts including secondary and cumulative implications of the works. In

particular the consultant, should be aware of any significant impacts that may occur as well as

any sensitive receptors. For example when construction occurs near built-up areas, poor

practices may result in air and noise pollution which may cause annoyance and affect the health

of neighbouring communities.

If necessary the contractor should seek advice from an approved specialist environmental

consultant.

The contractor should be aware that potential sources of pollution could include, but may not be

limited to, the following:-

• noise generated by machinery or construction activities.

• dusts and/or fumes produced by construction activities.

• disposal of solid wastes arising from construction activities, be they on or off site.

• discharge of waste waters, sewage or ground waters to land, sewer, surface water drain,

the marine environment or any other location.

• the disturbance of species or habitat either within or in the immediate vicinity of the site.

1.3 ENVIRONMENTAL MANAGEMENT AND MINIMISATION OF IMPACTS

Contract documents, specifications and drawings should be examined to establish whether any

activities which take place as part of the contract may have an impact upon the environment,

e.g.;

a) the disposal of waste waters to surface water drain, sewer or on land,

b) the production of noise, dusts or fumes,

c) the de-watering of ground and disposal of water arising,

d) the disposal of waste materials arising,

e) the damage to existing wildlife habitats due to construction activities.

In order to ensure that the contractor minimises all potential environmental impacts, and has

best working practices to minimise risks the consultant must also ensure that the contractor has

an appropriate Health, Safety Environmental Management System (HSEMS) in place. The

HSEMS aims to establish quality systems to consistently high health, safety and environmental

outcomes for the project as a whole.



PART TWO



For projects which are deemed to be environmentally sensitive, as defined by the regulatory

authority, the contractor will be required to develop a Construction Environmental Management

Plan (CEMP).

The CEMP is required to contain all aspects of a projects environmental management, and

should be prepared by the main contractor before work commences. This aims to implement

mitigation measures that may be required as defined by any previous environmental

assessments conducted by the Municipality. The CEMP should contain best practice sources

documents which can be used to address significant environmental impacts. These are generic

and should be applied to the site conditions via the environmental control plan.

The CEMP should be developed in accordance with ERWDA Techncial Guidance and should

include details of:

• Environmental Control Plan

• Work Scheduling

• Land Disturbance

• Stormwater Management

• Control Installations and Measures

• Soil Stockpiles

• Special Operational Precautions

• Contingency Plans

• Rehabilitation

• Maintenance, Inspections and Surveillance

• Ongoing Assessment and Management

The CEMP is the responsibility of the contractor. The consultant is required to ensure that the

contractor fulfils all their obligations as stated in the CEMP. Both the consultant and the

contractor may require the input of an approved specialist environmental consultant.

1.4 ENVIRONMENTAL MONITORING AND ONGOING INSPECTIONS

Construction sites are constantly changing and systems need to be in place to modify control

measures to maintain their effectiveness. Frequent inspection and monitoring may therefore be

required to continually check the effectiveness of measures. The CEMP should also be

updated to address deficiencies identified by the monitoring or audit program as new impacts

are identified through surveillance.

Any laboratory testing is required to be conducted in ERWDA approved laboratories.

Monitoring methodologies and plans need also to be approved by ERWDA.



PART TWO



1.5 THE FEDERAL LAW ON PROTECTION AND DEVELOPMENT OF THE ENVIRONMENT (1999)

The contractor should make himself aware of relevant articles in the above law. In particular

he should be aware of the following:-

The law aims at achieving the following purposes:-

article 2

To combat pollution of all forms and to prevent any immediate or long-run damage or effects

due to economic, agricultural, industrial or reconstruction development plans and programs

aimed at improving quality of life and to secure co-ordination between the Authority and the

parties involved in the environment protection, conservation of its diversity and natural

balance and to spread environmental awareness and anti-pollution principles.

articles 49-55

The contractor should make himself fully aware of the Executive Regulations which relate to

the above articles.

article 49

Machinery, engines or vehicles generating combustion beyond the limits specified by the

Executive Regulations shall not be used.

article 52

In carrying out drilling, construction, demolition, or transportation of whatsoever results

therefrom, including garbage or sands, all parties and individuals shall take the necessary

precautions in the course of practising such activities, as well as the precautions, needed for

their safe storage and transportation to prevent their scattering, in the manner to be shown in

the Executive Regulations.

article 54

• in carrying out production or service activities or otherwise, especially in operating

machinery, equipment, horns, loudspeakers all parties and individuals shall not exceed

the permissible limits for noise.

• the Executive Regulations shall show the tolerable limits for the maximum volume of

sound and the time limit to exposure thereto.

The contractor should make himself aware of the penalties which may applied for non-

compliance with this Law which could include:-

• death penalty,

• imprisonment

• maximum fine of 10 million Dirhams.



PART TWO



article 71

Any person, whose act or negligence causes damage to the environment or a third party,

due to violation of the provisions of this law or the regulations or decisions issued in

implementation thereof, shall be held responsible for all costs required for the handling or

elimination of such damage. He shall be bound as well to pay any consequent indemnity.

article 77

Whosoever pollutes drinking or ground waters, shall be punished with imprisonment for a

period of not less than one year and a fine not less than five thousand Dirhams and not more

than one hundred thousand Dirhams.



PART TWO

Document No. Revision Date Section title (iv)

ADM/H&S/Pt 2 01 March 2005 ADM TP & Emergency H&S Contact Details 1 of 2

ADM & TP H&S Contact Details Telephone No. Fax No.

Chairman of ADM H&S Committee Eng. Ibrahim Hussain Baquer 02-6771821 02-6724417

Building Directorate Health and Safety Unit Eng. Raafat Radi Elias 02-6955173 02-6724417

Building Directorate Health and Safety Unit Eng. Mohammed Saleh Al Naqeeb 02-6955787 02-6724417

Buildings Directorate Quality Assurance Eng. Marie Mahmoud Al Ghadi 050-6153144 02-6724417

Roads Directorate Eng. Issa Mubarak Al Mazrouie 02-6772227 02-6794518

Roads Directorate Dr. Rasin Kadri Mufti 02-6764002 02-6956367

Sewerage Directorate Eng. Nader Asaad Bin Taher 02-6711244 02-6790218

Town Planning Eng.Fadel ali Al Briki 02-6978283 02-6786716

Agriculture Section Eng. Helmy Abbas Abu Atia 02-6956716 02-6793699

Forestry Section Eng. Abdul Hakeem Eida El Jaberi 02-5839159 02-5839030

Agriculture Guidance Marketing and Livestock Eng. Ahmed Mohd. Al mutwaly Salim 02-6955451 02-6788724

Public Health and Environment El Wathiq Tibara Idris 02-6980349 02-6785961

Municipality Garage Mohamed Saeed Muhair El Qubaisi 02-4446500 02-4444038

Municipality Garage Hakeem Abdulla Nasser Shayaa 02-4446500 02-4444037

Stores Directorate Abdul Latif Ali Ibrahim Al Mansoori 02-4446619 02-4444746

General Transport Directorate

Tariq Mohammed Abdul Rahman Al Shahie 02-4071614 02-4431800

Financial Affairs Directorate Mohammed Osman Abasher 02-6955518

Traffic Signals (Roads Directorate) Eng. Majid Eid Ali Eidat Al Katheiry 02-6727324 02-6779173

Abu Dhabi Compost Factory Abdel Fatah Mohammed Abu El Nass 02-5554450 02-5555605

Industrial Security Directorate Elmor Mohammd El Neyadi 02-6956001 02-6790684

I.T. Section Zayed Ahmed El Hamely 02-6955910 02-6775877

Statistics Section Eisa Ali Al Hosani 02-6955055 02-6774919

Public Relations Section Fahad Salmeen Al Madhi 02-6955036 02-6780064



PART TWO

Document No. Revision Date Section title (iv)

ADM/H&S/Pt 2 01 March 2005 ADM TP & Emergency H&S Contact Details 2 of 2

Emergency Contact Details Telephone No.

FIRE/CIVIL DEFENCE 997

AMBULANCE SERVICE 998

POLICE 999

ELECTRICITY 4464677

WATER 991

ETISALAT 8005500

ADNOC 6023177

COAST GUARD 6731900

SECTION 1

SECTION 1


DEFINITION 1

INTRODUCTION




1.1 GENERAL 2

1.2 ENVIRONMENTAL ASSESSMENT –

IDENTIFYING POTENTIAL IMPACTS ON THE ENVIRONMENT 3

1.3 ENVIRONMENTAL MANAGEMENT AND MINIMISATION OF IMPACTS 3

1.4 ENVIRONMENTAL MONITORING AND ONGOING INSPECTIONS 4

1.5 THE FEDERAL LAW ON PROTECTION AND DEVELOPMENT OF THE 5

ENVIRONMENT (1999)



PART TWO



SECTION 1


DEFINITION

The key issues that must be taken into consideration when undertaking any work which may, to any

extent, impact the environment.

INTRODUCTION

During construction certain development projects pose a significant risk to the environment. This risk

must be addressed through the consideration of Environmental Protection which involves

environmental assessment, management and monitoring to ensure that the effects of development

are not significantly detrimental. All personnel are responsible for considering the environmental

implications of their activities. This should be overseen by the consultant, or a specialist

environmental consultant where appropriate. Construction practices that fail to control pollution can

cause damage to the terrestrial environment, upset ecological systems and wildlife communities, and

result in the contamination of land and groundwater.

The issue of environmental protection during the contract period should be discussed with the

consultant prior to the site hand-over. Where deemed appropriate the consultant should seek

guidance from an approved specialist environmental consultant. Stiff penalties can be brought to bear

upon individual persons and companies whose actions result in damage, be it temporary or

permanent, direct or indirect, to the environment.


Federal Law No. 24 (1999) on Protection and Development of the Environment

Ministerial Order No.32 (1982) regarding protection of employers against occupational hazards

Local orders on discharge and disposal of wastes (Environmental Protection Section - Food and

Environmental Control Centre - Abu Dhabi Municipality)



PART TWO




ERWDA (2003).Technical Guidance Document (TG-0003R)

Standards and Limits for:

A. Pollution to Air and Marine Environments.

B. Occupational Exposure.

C. Pesticides and Chemical Use. Draft July 6 2003.

ERWDA (2003). Technical Guidance Document

Development of Construction Environmental Management (CEMP) - Onshore. Draft November 2003.


The contractor should contact the Environmental Protection Section of the Food and Environmental

Control Centre of Abu Dhabi Municipality to ascertain what standards and/or regulations are currently

in force.

1.1 GENERAL

• all contracts, whether new or existing, must comply with the Federal law and enforcing

regulations on environmental protection and also any local orders currently in place.

• it is recommended that all contracts, whether new or existing, comply with best practice

and technical guidance.

• in accordance with best practice recommendations, the contractor must have in place/be in

the process of developing an integrated Health, Safety Environmental Management

System in order to minimise risks.

• the contractor should make himself aware of any risks to the environment which may occur

within or outside the agreed site area as a result of his activities.

• the contractor should seek advice from an approved specialist environmental consultant as

to what measures should be taken to prevent or reduce to an acceptable level (as agreed

by the local authorities) the impact on the environment of activities taking place under the

contract in question.

• the contractor should have procedures in place to enable the monitoring of all discharges

into the environment, be they liquid, solid or gaseous and ensure adherence to permissible

threshold emission levels. Scrutiny of data arising from environmental monitoring may be

undertaken by the relevant authorities.



PART TWO



1.2 ENVIRONMENTAL ASSESSMENT-

IDENTIFYING POTENTIAL IMPACTS ON THE ENVIRONMENT

In order the have a full appreciation of the all potential environmental implications of a project,

the consultant must be familiar with all details any previous environmental studies,

conducted/instructed by Abu Dhabi Municipality. This should include the identification of all

direct and indirect impacts including secondary and cumulative implications of the works. In

particular the consultant, should be aware of any significant impacts that may occur as well as

any sensitive receptors. For example when construction occurs near built-up areas, poor

practices may result in air and noise pollution which may cause annoyance and affect the health

of neighbouring communities.

If necessary the contractor should seek advice from an approved specialist environmental

consultant.

The contractor should be aware that potential sources of pollution could include, but may not be

limited to, the following:-

• noise generated by machinery or construction activities.

• dusts and/or fumes produced by construction activities.

• disposal of solid wastes arising from construction activities, be they on or off site.

• discharge of waste waters, sewage or ground waters to land, sewer, surface water drain,

the marine environment or any other location.

• the disturbance of species or habitat either within or in the immediate vicinity of the site.

1.3 ENVIRONMENTAL MANAGEMENT AND MINIMISATION OF IMPACTS

Contract documents, specifications and drawings should be examined to establish whether any

activities which take place as part of the contract may have an impact upon the environment,

e.g.;

a) the disposal of waste waters to surface water drain, sewer or on land,

b) the production of noise, dusts or fumes,

c) the de-watering of ground and disposal of water arising,

d) the disposal of waste materials arising,

e) the damage to existing wildlife habitats due to construction activities.

In order to ensure that the contractor minimises all potential environmental impacts, and has

best working practices to minimise risks the consultant must also ensure that the contractor has

an appropriate Health, Safety Environmental Management System (HSEMS) in place. The

HSEMS aims to establish quality systems to consistently high health, safety and environmental

outcomes for the project as a whole.



PART TWO



For projects which are deemed to be environmentally sensitive, as defined by the regulatory

authority, the contractor will be required to develop a Construction Environmental Management

Plan (CEMP).

The CEMP is required to contain all aspects of a projects environmental management, and

should be prepared by the main contractor before work commences. This aims to implement

mitigation measures that may be required as defined by any previous environmental

assessments conducted by the Municipality. The CEMP should contain best practice sources

documents which can be used to address significant environmental impacts. These are generic

and should be applied to the site conditions via the environmental control plan.

The CEMP should be developed in accordance with ERWDA Techncial Guidance and should

include details of:

• Environmental Control Plan

• Work Scheduling

• Land Disturbance

• Stormwater Management

• Control Installations and Measures

• Soil Stockpiles

• Special Operational Precautions

• Contingency Plans

• Rehabilitation

• Maintenance, Inspections and Surveillance

• Ongoing Assessment and Management

The CEMP is the responsibility of the contractor. The consultant is required to ensure that the

contractor fulfils all their obligations as stated in the CEMP. Both the consultant and the

contractor may require the input of an approved specialist environmental consultant.

1.4 ENVIRONMENTAL MONITORING AND ONGOING INSPECTIONS

Construction sites are constantly changing and systems need to be in place to modify control

measures to maintain their effectiveness. Frequent inspection and monitoring may therefore be

required to continually check the effectiveness of measures. The CEMP should also be

updated to address deficiencies identified by the monitoring or audit program as new impacts

are identified through surveillance.

Any laboratory testing is required to be conducted in ERWDA approved laboratories.

Monitoring methodologies and plans need also to be approved by ERWDA.



PART TWO



1.5 THE FEDERAL LAW ON PROTECTION AND DEVELOPMENT OF THE ENVIRONMENT (1999)

The contractor should make himself aware of relevant articles in the above law. In particular

he should be aware of the following:-

The law aims at achieving the following purposes:-

article 2

To combat pollution of all forms and to prevent any immediate or long-run damage or effects

due to economic, agricultural, industrial or reconstruction development plans and programs

aimed at improving quality of life and to secure co-ordination between the Authority and the

parties involved in the environment protection, conservation of its diversity and natural

balance and to spread environmental awareness and anti-pollution principles.

articles 49-55

The contractor should make himself fully aware of the Executive Regulations which relate to

the above articles.

article 49

Machinery, engines or vehicles generating combustion beyond the limits specified by the

Executive Regulations shall not be used.

article 52

In carrying out drilling, construction, demolition, or transportation of whatsoever results

therefrom, including garbage or sands, all parties and individuals shall take the necessary

precautions in the course of practising such activities, as well as the precautions, needed for

their safe storage and transportation to prevent their scattering, in the manner to be shown in

the Executive Regulations.

article 54

• in carrying out production or service activities or otherwise, especially in operating

machinery, equipment, horns, loudspeakers all parties and individuals shall not exceed

the permissible limits for noise.

• the Executive Regulations shall show the tolerable limits for the maximum volume of

sound and the time limit to exposure thereto.

The contractor should make himself aware of the penalties which may applied for non-

compliance with this Law which could include:-

• death penalty,

• imprisonment

• maximum fine of 10 million Dirhams.



PART TWO



article 71

Any person, whose act or negligence causes damage to the environment or a third party,

due to violation of the provisions of this law or the regulations or decisions issued in

implementation thereof, shall be held responsible for all costs required for the handling or

elimination of such damage. He shall be bound as well to pay any consequent indemnity.

article 77

Whosoever pollutes drinking or ground waters, shall be punished with imprisonment for a

period of not less than one year and a fine not less than five thousand Dirhams and not more

than one hundred thousand Dirhams.

SECTION 2

SECTION 2

WORKING IN HIGH TEMPERATURES AND REMOTE LOCATIONS

DEFINITION 1

INTRODUCTION


2.1 DRIVING TO REMOTE SITES 2

2.2 WEATHER 3

2.3 INSECTS, SPIDERS AND SNAKES 4

2.4 EFFECT OF HEAT WHILST WORKING ON SITE 5

2.5 PREVENTION OF HEAT RELATED CONDITIONS 6

2.6 VEHICLES, HEAVY EQUIPMENT AND PLANT 7

2.7 PERSONAL PROTECTIVE EQUIPMENT 7



PART TWO


ADM/H&S/Pt 2 01 March 2005 WORKING IN HIGH TEMPERATURE AND REMOTE LOCATIONS 1 of 7

SECTION 2

WORKING IN HIGH TEMPERATURES AND REMOTE LOCATIONS

INTRODUCTION

Driving and working in remote areas such as the Deserts of the UAE, and working on sites where the

temperature exceeds 75° F, requires planning and preparation to assure the safety of the men and

resources involved in the activity.

Complacency while working in the desert, and not appreciating the effects of excessive heat on sites

can lead to serious problems.

It is the management’s responsibility to ensure that the appropriate resources and training are in place

before sending his workforce into remote areas, and working in high temperatures.

DEFINITIONS

remote locations

A remote work site e.g. (working in the desert), that requires all resources brought in to complete the

activity safely.

high temperature

When temperature on any site in any location, exceeds 210 Celcius (75

0Farenheit)


Ministerial Order No. 32 (year 1982) Articles 5 & 7



PART TWO



2.1 DRIVING TO REMOTE SITES

• make sure of the location of the site and how to get there, if not take someone who does.

• allow plenty of time to make the journey.

2.1.1 check your vehicle

• oil pressure.

• tire pressure and condition, including

the spare.

• battery.

• radiator level.

• petrol tank level.

2.1.2 ensure the availability of the following

• drinking water.

• tool kit, jack and jack handle.

• owners manual.

• tire pressure gauge.

• shovel

• block of wood for the jack.

• mobile phone or two-way radio.

2.1.3 supplies required

• warm clothing.

• food.

• toilet roll

• sunshade (space blanket).

• fluorescent marking strips.

• flares and smoke canisters.

• 10 litres of water per man.

2.1.4 checking out procedure

• a plan of your route, be specific.

• your time of departure.

• your time of arrival.

• type, colour and vehicle number.

• the name of the driver and all

passengers.

• remember to book in on your arrival and

call departure point to confirm your

arrival.



PART TWO



2.1.5 break down or lost

• never leave the vehicle.

• call for help.

• get comfortable and wait for help to

come to you.

• set up sunshade.

• layout marking strip on high ground.

• drink water as you require it, do not

save it for later.

• keep in contact with base site if possible,

use high ground.

• keep calm and rest as much as possible.

• release a flare and smoke canister if you

hear an approaching vehicle or aircraft.

2.2 WEATHER

2.2.1 dust storm

• slow down immediately and get off the highway

• turn your lights off

• stay in your vehicle and wait until it is all over

2.2.2 flash flood

• monitor road and weather reports before

travelling

• flash floods can fill low spots to dangerous levels

very quickly

• do not drive into water on the road if you can’t

tell how deep it is



PART TWO



2.3 INSECT, SPIDERS AND SNAKES

2.3.1 bark scorpion

• this is the small light – coloured one (a little over 2 inches fully

grown).

• a sting will be very painful to touch and commonly causes

numbness around the area.

• allergic sensivity may result in swelling of the tongue and

difficulty in breathing. If so, you should get emergency medical

assistance.

2.3.2 black widow spider

• symptoms may include muscle cramps, nausea, vomiting,

headache and hypertension.

2.3.3 bees, wasps, ants and other bugs

• Any of these may result in itching, welts, nausea,

headache, and in more severe reactions, difficulty in

breathing.

2.3.4 general recommendations for avoiding insect danger

• never put your hands or feet anyplace you cannot see.

• shake out all clothes and shoes before reaching into them.

• never go barefoot.

• do not wear perfume or bright clothes in the desert.

2.3.5 general treatment

Since you may not know what bit you, the following are a few things you can do that are

generally recommended for most of the above insect stings:-

• wash the affected area with soap and water.

• apply ice, using a layer of cloth between it and the skin (no longer than 10 minutes at a

time).

• elevate the area if possible.

• seek medical attention as soon as possible.

If you have not had a Tetanus booster in the past 10 years, you should get one within 72 hours

following the sting.



PART TWO



2.3.6 snakes

Snakes are best avoided by never putting

your hands or feet where you can’t see.

If you should sustain a snake bite, keep as

quiet as possible and get emergency medical

aid immediately.

2.4 EFFECT OF HEAT WHILST WORKING ON SITE

The two main effects are called heat exhaustion and heat stroke. They are quite different and

must be recognised since the treatment of the two conditions differs.

Heat exhaustion can be compared to a faulty radiator and heat stroke can be compared to a

breakdown of the thermostat.

2.4.1 heat exhaustion

This is caused by failure of the body’s cooling process due to a lack of water and salt caused

either by excessive sweating or insufficient intake.

look for

• complaints of tiredness, drowsiness,

thirst, dryness of the throat, cramps and

headache.

• a decrease in the amount of urine

produced.

• the temperature may be normal or

slightly raised.

• there may be a feeling of sickness or

actual vomiting.

• sweating still occurs.

• a tendency to faint.

treatment

• replace fluids, large quantities of water or isotonic saline (1/4 teaspoon of salt in 1 litre

of water.

• if the patient is vomiting give water as above and seek medical treatment immediately,

as intravenous fluid replacement may be required.



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2.4.2 heat stroke

This is caused by a breakdown or overload of the body’s heat regulating mechanism as a

result of an excessive build up of heat in the body due to a high surrounding temperature

and/or the production of excessive heat by muscular exercise.

look for

• a sudden dramatic rise in body temperature above 40 o c.

• the cessation of sweating.

• the patient will feel very hot and dry.

• there may be disorientation, struggling or convulsions or unconsciousness.

treatment

• immediate cooling of the body is essential to prevent death.

• remove patient to a cool environment.

• wrap in wet sheets and/or sponge down with cold water. Immerse in cold water bath if

possible until temperature is down to 39oc, at which time cooling should be stopped to

avoid shock.

• seek medical attention as soon as possible.

2.5 PREVENTION OF HEAT RELATED CONDITIONS

• drink enough water to replace sweat loss. This may be from 5 litres to 10 litres per day

during summer months.

• take sufficient salt (the best way is with food).

• avoid alcohol intake before or during work.

• eat sparingly during the day.

• avoid exposure to the sun in the heat of the day, if possible arrange work during the

cooler hours.

• while working outside prepare shade over the task area if possible.

• wear light, loose clothing a hat and sunglasses.

• avoid overexposure to the direct rays of the sun.

• if stranded in the desert, take steps to maintain good fluid intake until rescued. Prepare

shade and stay with your vehicle. Reduce exercise.

• move workers to activities in shaded areas in shifts to prevent a build up of body heat.

Alternate heavy and light work activities.



PART TWO



2.6 VEHICLES, HEAVY EQUIPMENT AND PLANT

• keep equipment fluids up by regular inspections and checks.

• clean cab areas of rags and inflammable materials.

• keep a fire extinguisher in the cab of all equipment.

• prepare shade for the cab of equipment so as not to hinder the operator’s field of vision.

• park equipment in the shade whenever possible.

• inspect heavy equipment electrical system’s regularly.

• equipment and operators in remote areas of the site should be checked every 3 hours

min.

2.7 PERSONAL PROTECTIVE EQUIPMENT

• labourer’s in the field should be provided with light, loose coveralls.

• sunglasses and helmets to prevent direct exposure to the sun.

• gloves to prevent damage to hands when handling tools or equipment that has been

sitting in the sun.

• coolers and shade tents set-up at work activity areas.

SECTION 3

SECTION 3

NOISE AT WORK

INTRODUCTION 1


3.1 WHAT IS NOISE 2

3.2 HEALTH HAZARDS ASSOCIATED WITH NOISE 2

3.3 ESTABLISHING NOISE LEVELS 3

3.4 NOISE LEVELS AT PLANNING STAGE 4

3.5 REDUCING NOISE LEVELS 4

3.6 RECOMMENDED MAXIMUM EXPOSURE WITH PROTECTION 6

3.7 TYPICAL SOUND LEVELS OF THE MOST POPULAR

CONSTRUCTION AND PILING EQUIPMENT 6



PART TWO


ADM/H&S/Pt 2 01 March 2005 NOISE AT WORK 1 of 7

SECTION 3

NOISE

INTRODUCTION

Safety in the building industry has a high priority, however, health hazards are often less understood.

Many causes of occupational ill-health, including noise, are recognised by industry but can be difficult

to manage because there is often a long latency period before the disease or effect develops and

susceptibility varies.

Strategies for controlling occupational health risks are on the whole led by legislation and are seen as

requiring time and resources to develop and as not producing immediate direct cost benefits, for

example audiometry

Little wonder then that difficulty is often experienced by:

• designers (when taking into account health risks in the design and specifications)

• consultants (in highlighting health risks in the pre-tender health and safety plan)

• contractors (in determining when and at what level, health protection should be provided to their

employees)

• employees (in being aware of health risks and in using correctly the controls put in place or issued

to them for their protection)


Ministerial Order No.32 Year 1982 - Article (1)

Ministerial Order No.32 Year 1982 - Article (5) d

Ministerial Order No.32 Year 1982 - Article (15)



PART TWO



3.1 WHAT IS NOISE?

Noise is usually defined as unwanted sound. But strictly noise and sound are the same.

noise can:

• be a nuisance, resulting in disturbance and loss of enjoyment of life, loss of sleep and

fatigue

• it can distract attention and concentration, mask audible warning signals or interfere with

work, thereby being a factor in workplace accidents; and

• result in hearing impairment.

The danger levels for noise are identified as being, 85dBA and 90dBA. At 85dBA which is

known as the first action level, employees will probably have to shout to be heard at a

distance of 2m away from the person they are talking to, and must be provided with hearing

protection at their request.

At the second action level which is 90dBA or above, employees will probably have to shout

to be heard at a distance of 1 m away from the person they are talking to. The exposure of

employees to noise must be reduced as far as reasonably practicable, without the use of

hearing protection. If it cannot be reduced below this level then hearing protection must be

provided and reasonable steps taken to ensure that it is used; employees have a duty to use

hearing protection in such circumstances.

3.2 HEALTH HAZARDS ASSOCIATED WITH NOISE

The human ear is a delicate organ which is highly susceptible to damage, and this can

frequently be induced by the working environment,

There are two types of hearing loss associated with damage to the receptive hairs,

temporary and permanent threshold shift.

Temporary threshold shift is a temporary dullness in hearing after exposure to loud noises.

Hearing will subsequently recover, the time taken depends on factors such as loudness and

duration of the noise. If hearing does not fully recover after 48 hours, the level of hearing

loss that remains can be considered permanent.

There are two categories of ‘permanent threshold shift’

noise induced or occupational deafness, which results when the sufferer has been

regularly exposed to noise over a long period of time. Normally, hearing loss will be similar in

both ears and increase with continued exposure to the noise.

acoustic trauma, occurring with exposure to a very high sound level over a short period of

time, in some cases resulting in perforation of the eardrum. Once permanent damage has

occurred to the inner ear, it is irreversible.



PART TWO



3.3 ESTABLISHING NOISE LEVELS

3.3.1 unit of measurement

• the unit of measurement for sound levels is the

decibel dB.

• this scale is logarithmic which means that 90dB is

ten times the intensity of 80 dB and a hundred

times the intensity of 70dB.

• an increase of 3dB doubles the sound intensity, so

that 87dB is twice as noisy as 84dB.

• sound level meters, used for measuring noise

levels have standard characteristics built into them,

which attenuate, or emphasis signals at different

frequencies, this is known as 'frequency weighting'.

• an instrument with a weighting corresponding to

the frequency response of the human ear (known

as an ‘A’ weighted scale) is commonly used on

building sites to measure noise from the dB(A).

(see Fig.1)

• noise meters vary considerably depending on type, size and cost, but even the

inexpensive range will give a reasonable indication of sound levels being produced. Most

instruments can be switched to 'slow' response which dampens the oscillation of the

reading needle to allow easier reading.

3.3.2 surveys

• noise surveys should only be carried out by a person who has received adequate training

in noise measurement techniques.

• surveys are advisable when it is necessary to shout in order to be audible to a person

about one metre away.

• if conversation would be difficult in the nearest building (with windows closed) noise

levels are probably excessive.

• when the sound level at a building facade is to be estimated, an addition of 3dB(A)

should be allowed for reflection.

• noise levels may be irregular or steady.

• a reasonably steady sound level is where the level fluctuates through a total of less than

8dB(A) on a slow response scale.

Fig. 1- Examples of Sound Level Meters Measuring “A” weighted scale.



PART TWO



3.3.3 maximum exposure

• recommended maximum exposure to equivalent continuous sound levels without

protection are listed (see table in section 24.6).

• these are minimum requirements and everything possible should be done to improve on

them and reduce exposure to noise.

3.4 NOISE LEVELS AT THE PLANNING STAGE

Attention should be given at the planning stage to the following factors:

• design of project, and of processes and equipment involved.

• alternative methods and processes.

• phasing of operations (especially if a number of contractors are working on site).

• municipality requirements.

• location of site, or sites if work involves changing locations.

• noise levels likely to be produced.

• site layout (i.e. siting of access points, batching plants etc.)

• hours of working.

• provision for controlling noise on site.

• disturbance of nearby residents (if this is likely, the situation and measures to be taken to

reduce noise should be explained to persons likely to be affected).

Note: Failure to plan the control of noise may lead to delay and increased cost later.

3.5 REDUCING NOISE LEVELS

Where noise cannot be avoided, it may be reduced by:

• siting or location of noise source (i.e. static plant)

• control of noise at source e.g. acoustic hoods/covers

• equipping individual with ear protectors

• a combination of these methods will often be necessary



PART TWO



3.5.1 siting or location

• removing source of noise - i.e. static plant, loading/unloading areas - to a distance

whenever possible

• orientating plant to direct noise away from living/working zones

• placing site buildings, stores, etc between noise source and noise sensitive areas.

• screening source with a barrier, wall, acoustic screen, spoil heap or locating source

behind partly completed buildings.

• the effectiveness of a noise barrier will depend on its dimensions, its position relative to

the source and the listener, and the material used for the barrier.

• care must be taken to ensure barriers do not, by reflecting sound, transfer the nuisance

from one sensitive area to another.

3.5.2 control of noise at source

• design and manufacture of equipment.

• mufflers, acoustic shields and exhaust silencers

for equipment. (see Figs. 2&3)

• use of alternative, less noisy equipment or

methods.

• acoustic screens and sheds enclosing operator.

• regular inspection and maintenance.

• absorbent mountings to reduce noise

transmission through structures.

3.5.3 ear protectors

• all practicable methods should be used to reduce noise

levels, but where these remain excessive and harmful,

ear protectors must be worn. Ear protectors are not a

substitute for other methods of noise control.

• individuals may be reluctant to wear protection, and

personnel at risk should be made aware of the damage

caused to hearing by excessive noise levels, which can

result in permanent less of hearing.

Fig.2 - Acoustic Gaskets fitted to a compressor.

Fig.3 - Soundproofing foam used for wall insulation.

Fig.4 - Standard pair of Ear protectors.



PART TWO



3.6 RECOMMENDED MAXIMUM EXPOSURE WITHOUT PROTECTION

Average Noise Level dB (A) Maximum Exposure in one working day

90 8 hours

93 4 hours

96 2 hours

99 1 hour

102 30 minutes

105 15 minutes

108 7 1/2 minutes

111 3 3/4 minutes

Notes:

• this is the noise level at the ear and not at the source

• the table above is based on the logramithic calculation where an increase of 3 dB (A) is

regarded as doubling the noise level or halving the exposure time.

3.7 TYPICAL SOUND LEVELS OF THE MOST POPULAR CONSTRUCTION

AND PILING EQUIPMENT

Sound Level dB (A) General Construction Equipment Piling Equipment

95 Hand tools - Electric

100 Hand tools - Air

101 Fork lifts

102 Hammer Drill

103 Dumpers

104 Concrete Mixer

105 Hand Tools

106 Tower Cranes

107 Circular Saw Bench

108 Trucks

109 Excavators 6Ton Drop hammer (Cased Piles)

110 Crawler Cranes

111 Ready Mix

112 Heavy Lorries

113 Hoists - Diesel

114 Loading Shovel

115 Rock Drill



PART TWO



Sound Level dB (A) General Construction Equipment Piling Equipment

116 Batching Plant Trench Hammer (Sheet Piles)

117 Generators Rotary Bored Piles

118 Loaders Screened Drop Hammer (Sheet Piles)

119 Cranes Lorry mounted

120 Compressors - Compactors Impact Boring (Driving Case Method)

121 2 ton drop hammer (precast concrete

piles)

125 Vibration System (sheet piles)

126 Resonant sheet 'H" Section

128 Single Acting Air Hammer (precast

Concrete)

136 Diesel Hammer (sheet piles)

138

Bulldozer - Graders

Double acting air hammer (sheet

piles)

Notes:

• sound levels are for guidance only and are taken at source.

• for accurate measurement of site noise - a survey is necessary.

• information should be sought from plant hire company regarding machines on site.

• noise level emitted from the machines will be affected by the competence of the operator

and the quality of maintenance.

SECTION 4

SECTION 4

OCCUPATIONAL HEALTH

INTRODUCTION 1


4.1 HEALTH HAZARDS 2

4.2 TOXICITY OF SUBSTANCES 2

4.3 ROUTES OF ENTRY 3

4.4 MINSTRIAL DECISON NO. (37/2) YEAR 1982 – 4

MEDICAL CARE WHICH THE EMPLOYER IS

OBLIGED TO PROVIDE TO HIS WORKERS.



PART TWO


ADM/H&S/Pt 2 01 March 2005 OCCUPATIONAL HEALTH 1 of 7

SECTION 4

OCCUPATIONAL HEALTH

INTRODUCTION

Occupational health anticipates and prevents health problems which are caused by the work which

people do. In some circumstances the work may aggravate pre-existing medical condition and

stopping this is also the role of occupational health.

Health hazards often reveal their effects on the human body only after the passage of time; many have

cumulative effects, and in some cases the way this happens is not fully understood.

Because the effects are often not immediately apparent, it can be difficult to understand and persuade

others that there is a need for caution and control.

Good occupational hygiene practice encompasses the following ideas:-

• recognition of the hazard or potential hazard

• quantification of the extend of the hazard - usually by measuring physical/chemical factors and

their duration, and relating them to known or required standards.

• assessment of risk of actual conditions of use, storage, transport and disposal.

• control of exposure to the hazard through design, engineering, working systems, the use of

personal protective equipment and biological monitoring.

• monitoring change in the hazard by means of audits or other measurement techniques, including

periodic re-evaluation of work conditions and systems.


Ministerial Decision No. (37/2) Year 1982 re-

The Medical - Care which the Employer is Obliged to Provide to his Workers.



PART TWO



4.1 HEALTH HAZARDS

Health hazards can be divided into four broad categories: physical, chemical, biological and

ergonomic. Examples of the categories are:

• physical — air pressure, heat, dampness, noise, radiant energy, electric shock

• chemical — exposure to toxic materials such as dusts, fumes and gases

• biological — infection, e.g. tetanus, hepatitis and legionnaire’s disease

• ergonomic — work conditions, stress, man-machine interaction

4.2 TOXICITY OF SUBSTANCES

Toxicity is the ability of a substance to produce injury once it reaches a site in or on the body.

The degree of harmful effect which a substance can have depends not only on its inherent

harmful properties, but also on the route and the speed of entry into the body.

Substances may cause health hazards from a single exposure, even for a short time (acute

effect) or after prolonged or repeated exposure (chronic effect). The substance may affect

the body at the point of contact, when it is known as a local agent, or at some other point,

when it is described as a systemic agent.

Absorption is said to occur only when a material has gained access to the bloodstream and

may consequently be carried to all parts of the body.

4.2.1 what makes substances toxic?

The effect a substance will have on the body cannot always be predicted with accuracy, or

explained solely on the basis of physical and chemical laws. The influence of the following

factors combines to produce the effective dose:

• quantity or concentration of the substance

• the duration of exposure

• the physical state of the material, e.g. particle size

• its affinity for human tissue

• its solubility in human tissue fluids

• the sensitivity to attack of human tissue or organs

4.2.2 long and short-term exposure

Substances which are toxic can have a toxic effect on the body after only one single, short

exposure. In other circumstances, repeated exposure to small concentrations may give rise

to an effect. A toxic effect related to an immediate response after a single exposure is called

an acute effect. Effects which result after prolonged (hours or days or much longer) are

known as chronic effects. Chronic implies repeated doses or exposures at low levels: they



PART TWO



generally have delayed effects and are often due to unrecognised conditions which are

therefore permitted to persist.

4.3 ROUTES OF ENTRY

Substances harmful to the body may enter it by three main routes.

These are:

Absorption - through the skin, including entry through cuts and abrasions, and the

conjunctiva of the eye. Organic solvents are able to penetrate the skin, as a result of

accidental exposure to them or by washing. Tetraethyl, lead and toluene are examples.

Ingestion - through the mouth, which is generally considered to be a rare method of

contracting industrial disease. However, the action of the main defence mechanisms

protecting the lungs rejects particles and pushes them towards the mouth, and an estimated

50 per cent of the particles deposited in the upper respiratory tract and 12.5 per cent from

the lower passages are eventually swallowed.

Inhalation - the most important route of entry, which can allow direct attacks against lung

tissue which bypass other defences such as those of the liver. The lungs are very efficient in

transferring substances into the body from the outside environment, and this is the way

inside for 90 per cent of industrial poisons.

4.3.1 results of entry

Having gained entry into the body, substances can have the following effects:

Cause diseases of the skin such as:

Non-infective dermatitis - an inflammation of the skin especially on hands, wrists and

forearms. This can be prevented by health screening, good personal hygiene, use of barrier

creams and/or protective clothing.

Scrotal cancer - produced by rubbing contact with workers’ clothing impregnated with a

carcinogen such as mineral oil, in close contact with the scrotum. This can be prevented by

substitution of the original substance, by use of splash guards, and by provision of clean

clothing and washing facilities for soiled work clothing.

Cause diseases of the respiratory system such as:

Pneumoconiosis - resulting from exposure to dust which deposits on the lung, such as

metal dust and man-made mineral fibre. Other examples of these fibroses of the lungs are

silicosis due to the inhalation of free silica, and asbestosis from exposure to asbestos fibres.

Humidifier fever — giving influenza-like symptoms and resulting from contaminated

humidifying systems.

Legionnaire’s disease - from exposure to legionella bacteria.

Cause cancer and birth defects - by encouraging cells to undergo fundamental changes by

altering the genetic material within the cell. Substances which can do this are carcinogens,



PART TWO



which cause or promote the development of unwanted cells as cancer.

Examples are asbestos, mineral oil, hardwood dusts and arsenic. Teratogens cause birth

defects by altering genetic material in cells in the reproductive organs, and cause abnormal

development of the embryo. Examples are organic mercury and lead compounds. Mutagens

trigger changes affecting future generations.

Cause asphyxiation - by excluding oxygen or by direct toxic action. Carbon monoxide does

this by competing successfully with oxygen for transport in the red cells in the blood.

Cause central nervous system disorders - by acting on brain tissue or other organs, as in

the case of alcohol eventually causing blindness.

Cause damage to specific organs - such as kidneys and liver. An example is vinyl chloride

monomer (VCM).

Cause blood poisoning - and producing abnormalities in the blood, as in benzene

poisoning, where anaemia or leukaemia is the result.

4.4 MINSTRIAL DECISON NO. (37/2) YEAR 1982 RE MEDICAL - CARE

WHICH THE EMPLOYER IS OBLIGED TO PROVIDE TO HIS WORKERS.

The Minister of Labour and Social Affairs,

After taking cognizance of the Federal Law No (I) for the year 1972 in respect of the

jurisdiction of Ministries and power of and the laws amending thereto. And, the Federal Law

for the years 1980 in respect of the Regulation of Labour Relations and on the submission of

the Ministry’s undersecretary.

Is hereby decided:

Article (1)

The obligation of an employer for the medical treatment of workers shall be in accordance

with the medical care standards set forth in the provisions of this decision and within the

limits of available treatment in the State.

Article (2) An employer whose the number of employees in his establishment in not more than fifty in

one place or within an area the radius of which is twenty kilometres, shall provide at the work

place in his establishment with first aid kits.

Article (3)

An employer whose the number of his workers in one place or within an area the radius of

which is twenty kilometres, is exceeding fifty workers and less than two hundred, and in



PART TWO



addition to his obligation to provide first aid kits, must employ; nurse holding a nursing

certificate recognised by the Ministry o Health who shall be entrusted with rendering first aid

treatment The employer shall also appoint a doctor to treat workers at the place prepared by

him for that purpose and shall give then medicines required, all free of charge.

And if treatment requires a specialist doctor, the establishment doctor shall recommend in

writing for the treatment of the worker by a specialist provided that in such case. Treatment

expenses shall equally be shared by both the employer and the worker.

Article (4)

An employer whose employees are two hundred workers or more in one place or within an

area the radius of which is twenty kilometers shall provide the treatment facilities stipulated in

Article (2) and (3) of this decision in addition to his obligation to provide all other treatment

facilities in cases the treatment of which require specialist doctors, or undergo surgical

operations or otherwise, as well as necessary medicines, all of which are at the expense of

the employer.

If the worker is treated in a hospital or a governmental or private or charity clinic, the

employer shall pay to such hospital or clinic the expenses of treatment, medicines and the

admission fees of the worker as determined by the Ministry of Health for hospitals and

governmental clinics or according to the rates fixed by the management of such hospital, or

private clinic.

Article (5)

The doctor of an establishment which the number of its’ workers is two hundreds or more

must treat any disease in the normal way and dispense necessary medicines.

He shall refer the worker to a specialist doctor or to the hospital in cases which require so. In

such case the worker may not ask that his treatment shall he by a specialist doctor, or

undergoes a surgical operation or be treated at a hospital except upon the decision of the

establishment doctor or on the basis of a certificate issued by specialist and approved by the

medical administration or the concerned medical zone within which jurisdiction the

establishment is situated.

The worker may not ask for treatment by specialist doctors other than those determined by

the employer, nor in hospital not been agreed.

Article (6)

The place assigned for the workers clinic and for their treatment shall be as near as possible

from the work place and shall have adequate ventilation, lighting and healthily conditions;

and it shall be equipped with necessary equipments and devices.



PART TWO



Article (7) The expenses of transportation of workers to the clinic shall be paid by the employer and at

the times specified for treatment or medical check-up.

However, the worker shall not be entitled to such expenses unless he complies with the

instructions of the employer as to the times specified for treatment or medical examination at

the clinic except in emergencies or urgent cases.

The employer may designate means of transportation for transporting patients and injured

workers, and in such a case the worker may not refuse such transportation means if they are

suitable and shall not be entitled to transportation expenses if he refuses to use the

transportation means without justifiable reason.

Article (8)

If there is a fund in the establishment or a scheme providing medical services in which the

worker is contributing which gives the right to receive medical treatment for himself and the

members of his family, the employer shall reduce the subscription fees of the worker in such

fund or scheme to an amount equal to the expenses of his treatment which the employer

bears, pursuant to the provisions of this decision.

Article (9) An employer who employs fifty workers or more must display at the main gates used by

workers to enter to the workplace, the following information:

• The location of workers clinic.

• Days, and working hours of such clinic.

• Address of the hospital, and the specialist doctors who are entrusted to treat workers, and

timings of such treatment if the employer is bound to provide according to the provisions

of this decision.

Inspectors of the labour inspection division at the Ministry may instruct to display all the

foregoing information or some of them, as the case may be, at another place or suitable

places whenever they deem it necessary.

Information must be displayed in an easy a manner for workers to see.

Article (10)

Any employer who is employing workers from out of the country must be sure of their

physical fitness, through a certified medical certificate proving that which must be

authenticated by the official concerned authorities.

In all cases, the employer must be sure of the physical fitness of the worker employed by

him before he joins work after subjecting him to medical examination; the result of which

must be included in a written report approved by the competent authority at the Ministry.

be published in the official gazette and

shall the date of its publication.



PART TWO



Article (11)

Any employer must prepare for every worker employed by him a medical file including the

following:

• The result of medical examination of the worker at the time he joined work.

• The result of medical check-up, and the prescribed treatment whenever the worker

reports for medical check-up and any date thereof.

• The Results of medical analysis, or treatment and X-ray, if any.

• Result of medical examination to know whether the worker is suffering from chest or

dermatological disease.

• The period for which the worker was absent because of illness provided that every (4)

days of absence due to illness or accidents shall be shown separately.

Such files shall be confidential, and shall not be seen except by the treating doctor, or the

employer or who represents him.

Article (12)

An employer who employs fifty workers or more must send a list of two copies every three

months to the concerned labour department showing the number of workers who received

medical treatment at the expense of the employer, the nature ol their diseases and the days

of absence because of illness.

Article (13)

Compliance with the provisions of this decision shall not prejudice nor nullify any other

regulations related to medical treatment in the establishment if such regulations achieve

better medical care than those set forth herein.

Article (14) This decision shall be published in the official gazette and shall come into force from the date of its publication.

Seif Al Jarwan - Minister of Labour and Social Affairs

SECTION 5

SECTION 5

SUBSTANCES HAZARDOUS TO HEALTH INTRODUCTION 1 DEFINITION & CLASSIFICATION


5.1 SUBSTANCES HARMFUL BY INHALATION 2

5.2 SUBSTANCES HARMFUL BY INGESTION 4

5.3 PENETRATION HAZARDS 4

5.4 HAZARDOUS SUBSTANCE CONTROL 5



PART TWO


ADM/H&S/Pt 2 01 March 2005 SUBSTANCES HAZARDOUS TO HEALTH 1 of 5

SECTION 5

SUBSTANCES HAZARDOUS TO HEALTH INTRODUCTION

Hazardous substances are considered to be chemical materials and products which are used every

day for a variety of purposes, many of which are dangerous if not handled correctly, majority are toxic,

corrosive, flammable, oxidising or irritants and all pose a risk to workers, the public, and the

environment.

There are four routes by which chemical substances may enter the body and cause harm, inhalation,

ingestion, penetration and skin absorption, but the one by which building site workers are more at risk

is that of inhalation, and this section, in the main, gives priority to this.

DEFINITION & CLASSIFICATION

Chemicals are defined and classified according to type of hazard:

Class I Explosives

Class 2 Gases (flammable, non-flammable compressed gas oxidising gas and poisoning gas)

Class 3 Flammable liquids

Class 4 Flammable solids (spontaneously combust - dangerous on wetting)

Class 5 Oxidising agents & organic materials (Peroxides)

Class 6 Poisons & Infectious substances

Class 7 Radioactive substances

Class 8 Corrosives

MAIN APPLICABLE UAE LEGISLATION

Ministerial Order No. (32) For the Year of 1982. Article 6, 9, 18 & 23



PART TWO



5.1 SUBSTANCES HARMFUL BY INHALATION

When material in the air is breathed in it can consist of dust, vapour, gas, fumes or mist. It

may be mildly irritant or be highly poisonous.

The material may lodge in the mouth, nose or throat or be comprised of small enough

particles to penetrate the deep lung. It may be cleared from the respiratory tract by the

body’s natural mechanisms or may lodge in the lungs, or it may be absorbed by the body

and transported in the blood to other organs.

Solvent vapours, welding fumes, asbestos, legionella and silica are all inhalation toxins or

hazards.

5.1.1 dust, fumes and gasses

Some dusts are directly composed of toxic materials, such as silica or hardwood. Dusty

conditions are common in construction, especially on dry, windy sites and where there is

blasting, excavation, batching, plastering, crushing or demolition.

Where possible, dust inhibiting measures, including dampening of floors and surfaces,

vacuum cleaning and exhaust ventilation of power tools should be used. Some materials,

particularly metals and metal coatings, may be hazardous as dusts from cutting or grinding,

or as fumes when welding or gas cutting is in operation.

The fumes to which construction workers are typically exposed are related to hot work,

either welding or cutting. The standards of control, in order to prevent lead poisoning, metal

fume fever, or ill-health arising from inhaling paint fumes when paint burning therefore relate

to the materials made airborne in such processes.

Typical dangerous dusts fumes and gasses encountered in the Building and Construction

Industry are tabled below:

Substance/Hazard Main Risk Main Precautions Required

DUST

ASBESTOS Asbestosis: Chronic Industrial Lung

disease.

Mesothelioma: Serious form of Lung

Cancer.

• dampen asbestos during cutting/sawing

operations.

• Wear appropriate R.P.E.

CADIUM (DUST OR FUMES) Cadium Poisoning, Long Term –

Emphysema & Kidney Damage.

• exhaust ventilation

• personal hygiene

• no eating, drinking or smoking on the job

• RPE may be necessary.

HARDWOOD DUST Dermatitis and Asthma

• adequate ventilation (where appropriate

• extraction equipment should be fitted to

machines

• suitable gloves where the wood is a

dermatitic agent



PART TWO




LEAD (DUST OR FUMES)

SILICA and QUARTZ DUST

Lead poisoning, anemia and systemic

poisoning

Silicosis, Breathing Difficulties leading

eventually to respiratory disablement.

• total enclosure, where practicable

• protective clothing which does not hold

dust • good personal hygiene and welfare

facilities (including showers, where

necessary)

• no eating, drinking or smoking on the job • where appropriate, the use of wet

methods

• total enclosure


• air-fed RPE

• impervious clothing

• segregation of other workers

CEMENT DUST Breathing Difficulties leading eventually to

respiratory disablement.

• where appropriate, the use of wet

methods



• respiratory protection

FUMES

WELDING & CUTTING

FUMES

Metal fume fever: Flu-like illness.

• ventilation at source




GASES, VAPOURS AND MISTS

CARBON MONOXIDE (CO)

(Toxic Gas)

CO poisoning; Drowsinness; Loss of

Muscular Control; Vomiting; Unconscious

and Death.

• high standard of ventilation, especially in

excavations and confined spaces

• controlled entry (e.g. by a permit to work)

• removal of source of CO from confined

spaces

CARBON DIOXIDE (CO2)

(Asphyxiant Gas)

Being heavier than Displaces Oxygen in

the Atmosphere, can lead to death due to

lack of oxygen.

• forced ventilation and extraction,

(especially where working in confined

spaces)

• air monitoring

• controlled entry by permit to work

• breathing apparatus and a rescue

procedure may be necessary

HYDROGEN SULPHIDE

(H2S)

(Highly Toxic and Flammable).

Low concentrations: Irritation of eyes,

nose and throat, headaches and

dizziness.

High concentrations: rapid death from

respiratory paralysis.

• forced ventilation and extraction

• air monitoring


• breathing apparatus and a rescue system

may be necessary

GASES LIQUEFIED

PETROLEUM GASES

(LPG).

Asphyxiation due to depletion of Oxygen,

could also have a narcotic effect.

• adequate high and low level ventilation in

site huts

• some appliances may need individual

flues

METHANE

Asphyxiant gas-highly - flammable and

explosive.

• high standard of ventilation

• air monitoring



may be necessary



PART TWO




SOLVENTS

(commonly used in paints,

paint strippers, varnishes,

mastics, glues, surface

coatings, etc).

Inhalation or absorption through the skin

can cause impaired judgement and

dizziness, followed by confusion,

sleepiness and unconsciousness.

Other symptoms are irritation of the

respiratory tract and headache. The

inhalation risk is greatest when solvents

are used in confined spaces; skin contact

can also lead to dermatitis.

• adequate ventilation

• air monitoring and the use of breathing

apparatus in confined spaces.

• rescue arrangements may be necessary.

• avoid skin contact, wear impervious

clothing where appropriate. • prevent accidental ingestion by good

hygiene;

• forbid the carrying of cigarettes in work

areas.

5.2 SUBSTANCES HAZARDOUS BY INGESTION

The hazards of such substances are not always obvious, and poisoning still occurs on

construction sites. In most cases the hazard can be eliminated or significantly reduce by

using substitute materials which are safer or less toxic, and ensuring that employees are

aware of the hazard when:

• using poisonous substances.

• establishing and instructing employees on safe systems of use and handling of chemical

products.

• ensuring clear and correct labelling - especially when products are decanted from their

original containers, prohibition of drinking and smoking in areas when chemicals are

used, or on sites where general contamination may be present.

• actively promoting programmes of health education, with particular regard to the need for,

and value of good personal hygiene,

• provision of appropriate personal protection including gloves respirators, etc., and

actively ensuring the use of special equipment.

5.3 PENETRATION HAZARDS

Construction workers can be exposed to infection through micro-organisms which can give

rise to a number of specific conditions, e.g.:

5.3.1 tetanus (lock-jaw)

This is a serious disease resulting from wound infection by an organism which has specific

ability to form spores. They are found in animal intestines and excreta and are highly

resistant to destruction, even by heat or antiseptics. They are, therefore, ubiquitous although

the disease itself is more commonly encountered in tropical countries.



PART TWO



Construction workers are vulnerable when breaking new ground and particularly when

working on sites previously used for agriculture. Large, dirty, lacerated wounds are very

susceptible, but infection can result from minor pricks or puncture wounds, e.g. treading on a

nail.

Workers should be encouraged to arrange an appropriate course of immunisation with

Tetanus through their own doctor. This should be arranged by the employer where company

medical facilities exist.

5.4 HAZARDOUS SUBSTANCE CONTROL

5.4.1 symbol signs

A systematic approach to the identification of potential chemical hazards is an essential

requirement

Signs shown below are an example of hazardous substance control safety signs

commonly used to identify hazards and mark areas to protect employees.

SECTION 5

SECTION 5

SUBSTANCES HAZARDOUS TO HEALTH INTRODUCTION 1 DEFINITION & CLASSIFICATION


5.1 SUBSTANCES HARMFUL BY INHALATION 2

5.2 SUBSTANCES HARMFUL BY INGESTION 4

5.3 PENETRATION HAZARDS 4




PART TWO



SECTION 5

SUBSTANCES HAZARDOUS TO HEALTH INTRODUCTION

Hazardous substances are considered to be chemical materials and products which are used every

day for a variety of purposes, many of which are dangerous if not handled correctly, majority are toxic,

corrosive, flammable, oxidising or irritants and all pose a risk to workers, the public, and the

environment.

There are four routes by which chemical substances may enter the body and cause harm, inhalation,

ingestion, penetration and skin absorption, but the one by which building site workers are more at risk

is that of inhalation, and this section, in the main, gives priority to this.

DEFINITION & CLASSIFICATION

Chemicals are defined and classified according to type of hazard:

Class I Explosives

Class 2 Gases (flammable, non-flammable compressed gas oxidising gas and poisoning gas)

Class 3 Flammable liquids

Class 4 Flammable solids (spontaneously combust - dangerous on wetting)

Class 5 Oxidising agents & organic materials (Peroxides)

Class 6 Poisons & Infectious substances

Class 7 Radioactive substances

Class 8 Corrosives


Ministerial Order No. (32) For the Year of 1982. Article 6, 9, 18 & 23



PART TWO



5.1 SUBSTANCES HARMFUL BY INHALATION

When material in the air is breathed in it can consist of dust, vapour, gas, fumes or mist. It

may be mildly irritant or be highly poisonous.

The material may lodge in the mouth, nose or throat or be comprised of small enough

particles to penetrate the deep lung. It may be cleared from the respiratory tract by the

body’s natural mechanisms or may lodge in the lungs, or it may be absorbed by the body

and transported in the blood to other organs.

Solvent vapours, welding fumes, asbestos, legionella and silica are all inhalation toxins or

hazards.

5.1.1 dust, fumes and gasses

Some dusts are directly composed of toxic materials, such as silica or hardwood. Dusty

conditions are common in construction, especially on dry, windy sites and where there is

blasting, excavation, batching, plastering, crushing or demolition.

Where possible, dust inhibiting measures, including dampening of floors and surfaces,

vacuum cleaning and exhaust ventilation of power tools should be used. Some materials,

particularly metals and metal coatings, may be hazardous as dusts from cutting or grinding,

or as fumes when welding or gas cutting is in operation.

The fumes to which construction workers are typically exposed are related to hot work,

either welding or cutting. The standards of control, in order to prevent lead poisoning, metal

fume fever, or ill-health arising from inhaling paint fumes when paint burning therefore relate

to the materials made airborne in such processes.

Typical dangerous dusts fumes and gasses encountered in the Building and Construction

Industry are tabled below:


DUST

ASBESTOS Asbestosis: Chronic Industrial Lung

disease.

Mesothelioma: Serious form of Lung

Cancer.

• dampen asbestos during cutting/sawing

operations.

• Wear appropriate R.P.E.

CADIUM (DUST OR FUMES) Cadium Poisoning, Long Term –

Emphysema & Kidney Damage.




• RPE may be necessary.

HARDWOOD DUST Dermatitis and Asthma

• adequate ventilation (where appropriate

• extraction equipment should be fitted to

machines

• suitable gloves where the wood is a

dermatitic agent



PART TWO




LEAD (DUST OR FUMES)

SILICA and QUARTZ DUST

Lead poisoning, anemia and systemic

poisoning

Silicosis, Breathing Difficulties leading

eventually to respiratory disablement.

• total enclosure, where practicable

• protective clothing which does not hold

dust • good personal hygiene and welfare

facilities (including showers, where

necessary)

• no eating, drinking or smoking on the job • where appropriate, the use of wet

methods

• total enclosure


• air-fed RPE

• impervious clothing

• segregation of other workers

CEMENT DUST Breathing Difficulties leading eventually to

respiratory disablement.

• where appropriate, the use of wet

methods




FUMES

WELDING & CUTTING

FUMES

Metal fume fever: Flu-like illness.

• ventilation at source




GASES, VAPOURS AND MISTS

CARBON MONOXIDE (CO)

(Toxic Gas)

CO poisoning; Drowsinness; Loss of

Muscular Control; Vomiting; Unconscious

and Death.

• high standard of ventilation, especially in

excavations and confined spaces

• controlled entry (e.g. by a permit to work)

• removal of source of CO from confined

spaces

CARBON DIOXIDE (CO2)

(Asphyxiant Gas)

Being heavier than Displaces Oxygen in

the Atmosphere, can lead to death due to

lack of oxygen.

• forced ventilation and extraction,

(especially where working in confined

spaces)

• air monitoring


• breathing apparatus and a rescue

procedure may be necessary

HYDROGEN SULPHIDE

(H2S)

(Highly Toxic and Flammable).

Low concentrations: Irritation of eyes,

nose and throat, headaches and

dizziness.

High concentrations: rapid death from

respiratory paralysis.

• forced ventilation and extraction

• air monitoring



may be necessary

GASES LIQUEFIED

PETROLEUM GASES

(LPG).

Asphyxiation due to depletion of Oxygen,

could also have a narcotic effect.

• adequate high and low level ventilation in

site huts

• some appliances may need individual

flues

METHANE

Asphyxiant gas-highly - flammable and

explosive.

• high standard of ventilation

• air monitoring



may be necessary



PART TWO




SOLVENTS

(commonly used in paints,

paint strippers, varnishes,

mastics, glues, surface

coatings, etc).

Inhalation or absorption through the skin

can cause impaired judgement and

dizziness, followed by confusion,

sleepiness and unconsciousness.

Other symptoms are irritation of the

respiratory tract and headache. The

inhalation risk is greatest when solvents

are used in confined spaces; skin contact

can also lead to dermatitis.

• adequate ventilation

• air monitoring and the use of breathing

apparatus in confined spaces.

• rescue arrangements may be necessary.

• avoid skin contact, wear impervious

clothing where appropriate. • prevent accidental ingestion by good

hygiene;

• forbid the carrying of cigarettes in work

areas.

5.2 SUBSTANCES HAZARDOUS BY INGESTION

The hazards of such substances are not always obvious, and poisoning still occurs on

construction sites. In most cases the hazard can be eliminated or significantly reduce by

using substitute materials which are safer or less toxic, and ensuring that employees are

aware of the hazard when:

• using poisonous substances.

• establishing and instructing employees on safe systems of use and handling of chemical

products.

• ensuring clear and correct labelling - especially when products are decanted from their

original containers, prohibition of drinking and smoking in areas when chemicals are

used, or on sites where general contamination may be present.

• actively promoting programmes of health education, with particular regard to the need for,

and value of good personal hygiene,

• provision of appropriate personal protection including gloves respirators, etc., and

actively ensuring the use of special equipment.

5.3 PENETRATION HAZARDS

Construction workers can be exposed to infection through micro-organisms which can give

rise to a number of specific conditions, e.g.:

5.3.1 tetanus (lock-jaw)

This is a serious disease resulting from wound infection by an organism which has specific

ability to form spores. They are found in animal intestines and excreta and are highly

resistant to destruction, even by heat or antiseptics. They are, therefore, ubiquitous although

the disease itself is more commonly encountered in tropical countries.



PART TWO



Construction workers are vulnerable when breaking new ground and particularly when

working on sites previously used for agriculture. Large, dirty, lacerated wounds are very

susceptible, but infection can result from minor pricks or puncture wounds, e.g. treading on a

nail.

Workers should be encouraged to arrange an appropriate course of immunisation with

Tetanus through their own doctor. This should be arranged by the employer where company

medical facilities exist.


5.4.1 symbol signs


requirement

Signs shown below are an example of hazardous substance control safety signs

commonly used to identify hazards and mark areas to protect employees.

SECTION 6

SECTION 6

OVERHEAD AND UNDERGROUND SERVICES

INTRODUCTION 1


6.1 UNDERGROUND SERVICES 2

6.2 DIGGING – MECHANICAL OR MANUAL 5

6.3 PILING 6

6.4 GENERAL PRECAUTIONS 6

6.5 BACKFILLING 7

6.6 OVERHEAD SERVICES 7


ADM/H&S/Pt 2 01 March 2005 OVERHEAD / UNDERGROUND SERVICES 1 of 9



PART TWO

SECTION 6

OVERHEAD AND UNDERGROUND SERVICES

INTRODUCTION

Live overhead lines have been responsible for a number of serious and fatal accidents on construction

sites when contact with the lines has been made by workmen or machines. The voltages may lie in

the range between 240 and 400,000 volts, and they all have lethal potential.

Underground services are, to a great extent, out of sight and out of mind until the time comes for

someone to dig a hole or start excavating. Accidental contacts with buried services such as electricity

cables and gas pipes may lead to serious injury or fatality.

The damage and injury can be avoided if the proper procedures outlined in this section are followed.


Ministerial Order No. (32) Year 1982 – Article (20)





PART TWO

6.1 UNDERGROUND SERVICES

6.1.1 types of buried services

The most obvious examples of buried services are those used to carry gas, electricity, water,

sewerage, and telecommunications services.

There are many other types of buried services, often confined to specific locations, which

are not likely to be the subject of public knowledge at all, they include services associated

with:

• hydraulics process fluids,

• pneumatics,

• petroleum and fuel oils,

• highway authorities,

• street lighting,

• military authorities.

Work in the vicinity of oil & gas transmission pipelines, often requires special measures to be

taken and the oil & gas company will supply detailed procedures on request.

6.1.2 risks and cost of damage

The greatest risk of injury lies in contacting electricity cables. Some people are electrocuted,

but the majority suffer major burns from the explosive arcing of the damaged cable. (see

Fig.1)

Most injuries are caused to persons using pneumatic drills of jackhammers, ruptured gas

pipes can cause a leak, a fire, or an explosion.

The consequences of damaging water pipes

and telephone cables may be less immediately

evident, but are nonetheless serious, both in

terms of disruption and costs. The interruption

of services can create serious problems for

places critically dependent upon them, for

example, hospitals, and many people are likely

to be inconvenienced.

Fig.1 - This is what can happen when you cut a live underground electrical cable.





PART TWO

The cost of damage can be considerable. The new generation of fibre optic

telecommunication cables are very expensive - and an apparently simple break may mean

the replacement of two kilometre length, at a cost measured in thousands of dirhams.

Indirect costs, in some cases resulting from loss of production and disruption of business

activities, will be borne by all affected, including those whose negligence caused the

incident.

6.1.3 checking for buried services

Before any digging takes places, a check must be made with all public and private utilities

and the owner or occupier of the land for the existence of services in the proposed work

area, and, where applicable, a site clearance/no objection form received from the

department concerned.

The following are the main points to be considered:

• any service said to exist, should be clearly marked on the site plans.

• when looking at plans, it should be borne in mind that reference points may have been

moved, surfaces may have been re-graded, services moved without authority or consent,

and that not all service connections or private services are shown.

• plans must be interpreted with care; a pencil on a map may cover a width equivalent to a

metre on the ground.

• where appropriate the route, when established, should be identified with paint, tape or

markers - not steel spikes, which might penetrate a cable or pipe.

• a line on a plan does not mean a pipe or cable is located exactly in the position marked. It

only indicates that it is roughly in that location.

• the exact position will only be known when the buried service is found, as in many cases,

there is no indication above the ground that a buried service exists. They may be found

almost anywhere and at any depth from immediately beneath the surface of the

pavement, or tarmac, to 1.5 metres or more.

• indications that buried services do exist include the presence of lamp posts, illuminated

traffic signs, telephone boxes, concrete or steel manhole covers, hydrant and valve pit

covers, etc.

• small concrete indicator posts, usually on the verge, or plaques on walls have this

specific function. Indicator posts belonging to water authorities often give the size of the

pipe and its distance from the post.

• the absence of posts or covers, must not be taken as evidence that there are no buried

services. Access covers can be a substantial distance apart.





PART TWO

• cables or pipes may be laid loose in the ground, run in earthenware, concrete, metal,

asbestos or plastic ducts, or be buried in cement-bound sand, loose sand, fine backfill or

material dissimilar from the surrounding ground.

• plastic marker tape, tracer wire, boards, tiles or slabs may have been laid above the

service to indicate that there is something below. These may, however, have been

removed or damaged in the past; they are also liable to be laterally displaced by ground

water or movement and thus no longer indicate the true location of the service.

It is now becoming a widespread

practice for brightly coloured

polythene tape or expanded plastic

mesh, sometimes incorporating

metallic tracer wire, to be placed in

the backfill above the pipe or service.

A text on the tape usually identifies

the service below, when uncovered,

these tapes indicate the presence of a

pipe or cable before any damage is

done.

(see Figs. 2 & 3)

Note: The absence of a tape should not be taken as evidence that there are no pipes or

cables at the location; it may simply mean that no marker tape was used.

6.1.4 use of cable and pipe locators

A wide range of instruments

is available for the detection

of buried services. Several

different principles may be

applied in the task of

detection, and an instrument

may incorporate more than

one of these like Hum

Detection, Radio Frequency,

Transmitter and Receiver,

Metal Detectors, etc. (see

Fig. 4)

Fig.2 - Example of expanded plastic mesh incorporating a metallic tracer wire.

Fig.3 - Example of brightly coloured tape used to identify underground services.

Fig.4 - Typical examples of cable and pipe locators commonly used to detect underground services





PART TWO

6.2 DIGGING - MECHANICAL OR MANUAL

Once the approximate location of a service has been identified using all available information

(including plans, marker posts, cable detection results etc). trial holes should be dug

carefully by hand to establish the exact location and depth of the service.

The following points should be considered prior to, and during digging operations:

• where two holes are dug at intervals, it should not be assumed that the service runs in a

straight line between them.

• mechanical excavators and power tools should not be used within 0.5 metres of the

indicated line of a service, unless prior agreement on a safe system of work has been

reached with the service owner.

• power tools may be used to break paved surfaces, but great care must be taken to avoid

over-penetration, since a service may have been laid at an unusually shallow depth,

especially in the vicinity of buildings or other services.

• power tools must never be used directly over the indicated line of a cable unless it has

been made dead or steps have been taken to prevent damage.

• excavations must be adequately supported, especially it more than 1.2 metres deep, or

dug in poor ground, at a location exposed to traffic vibration or near a building, or

embankment, etc.

• check with all utilities and land owners before commencing.

• assume presence of service when digging, even though nothing is shown on plans.

• detectors must be used, and close watch kept for signs or tapes, etc., indicating a buried

service.

• although there are recommended minimum depths for all services, they may be closer to

the surface than normal, especially in the vicinity of works, structures, or other services.

• markers such as plastic tape, tiles, slabs or battens may have been displaced, and not

indicate the exact location of the buried service.

• some electric cables, gas pipes and water pipes look alike. Ensure proper identification

before working on them.

• spades and shovels are safer than forks and pickaxes.

• careful use of spades and shovels enables services, which could easily be damaged by a

fork or a pickaxe forced into the ground, to be safely uncovered.

• rocks, stones, boulders, etc., should be carefully levered out.

• over-penetration of the ground or surface with hand-held power tools is a common cause

of accidents.





PART TWO

• if an excavator or digger is being used near any service, extra care must be taken in case

the service is damaged or broken.

• when possible, no one should be near the excavator or digger while it is digging.

• if the service is embedded in concrete or paving material, the utility or owner should de-

energise it or otherwise make it safe, or approve a safe system of work before it is broken

out.

• closed, capped, sealed, loose or pot ended services should always be assumed to be live

or charged, not dead or abandoned, until proven otherwise.

• follow the guidelines and advice issued by the electricity, gas, water and

telecommunication authorities.

6.3 PILING AND DRILLING

Piling, drilling, thrust boring, bar holing and augering must never be commenced until all the

necessary steps and precautions have been taken, and a safe system of work has been

devised and implemented. (see Pt 2 section 26) for further information on Piling.

Services shown or thought to be nearby should be exposed by hand digging to establish

their precise location.

6.4 GENERAL PRECAUTIONS

6.4.1 protection of services

Even if a service is exposed in the bottom of a trench or excavation, it should be protected

with suitable timber or other material to prevent damage; e.g.

• services across a trench or along a trench above the bottom should be supported by

slings or props, to avoid unnecessary stresses. In cases of doubt, advice should be

sought from utilities or the owner.

• cables and services must never be used as jacking or anchorage points, or as footholds

or climbing points.

• if a service pipe or cable needs to be moved to allow work to progress, the owner should

be consulted and advice sought.

6.4.2 reporting damage

Any damage to buried services must be reported to the owners. Minor damage to the sheath

of a cable or to a coating on a pipe can result in moisture penetration, corrosion and

subsequent failure. A cable pulled and stretched may result in a conductor or core broken

and an earthenware or concrete duct broken may prevent a service being installed.





PART TWO

6.4.3 gas pipe is fractured or starts leaking

• evacuate all personnel from area.

• enforce no smoking no naked lights.

• prevent approach by public or vehicles.

• inform gas authority immediately.

6.4.4 if an electricity cable is broken

• avoid contact with it.

• do not attempt to disentangle it from excavator or digger buckets, etc.

• jump clear of excavators or diggers - do not climb down.

• inform electricity authority.

• keep everyone clear.

6.4.5 underground telecommunication cables

• leave alone.

• Inform Etisalat

6.4.6 breakage of any other service pipe or cable

• leave alone.

• inform owner.

6.5 BACKFILLING

• surplus concrete, hard core, rock, rubble, flint, etc., must never be tipped onto a service

while backfilling a trench or hole, since it may result in damage.

• selected backfill material should be adequately settled and compacted, care being taken

to avoid mechanical shocks to the service pipe or cable.

• warning tapes, tiles, etc., should be placed above the service.

• when gas service pipes have been exposed, advice on backfill should be sought from the

gas companies.

6.6 OVERHEAD SERVICES

6.6.1 general

where applicable.





PART TWO

On sites the electricity supply will generally be obtained either from Electricity Department or

from site generators.

Overhead lines belonging to A.D.W.E.A. are subject to the requirements of their rules. High

voltage overhead lines are not normally insulated and comprise bare conductors mounted

on insulators on steel or wooden towers or poles.

Low and medium voltage lines may be insulated or uninsulated but, in either case, care is

necessary if hazards and accidents are to be avoided.

Where any electrically charged overhead cable or apparatus is liable to be a source of

danger to persons employed on the sites, all practicable precautions shall be taken to

prevent such danger by the provision of adequate and suitably placed barriers. (see Fig.5)

6.6.2 precautions against danger from overhead lines

sites where plant, e.g., mobile cranes, excavators, trucks may pass under overhead

lines

• where a roadway or passage is required under a line the crossing should be at right

angles to the line and be restricted to the smallest possible working width for the type of

plant using the roadway.

• this width should not exceed 10 metres.

• such crossings should be restricted to the smallest possible number and should be

fenced to give a clear indication of the roadway, and goalposts should be erected on both

sides of the overhead line to act both as gateways and height limits.

• the height and position of such goalposts will depend upon the voltage of the overhead

line and A.D.W.E.A. will advice on these points. (see Fig.6) below.

275 or 440KV 132 KV 33KV 11KV Low Voltage

Minimum Clearance 7m

Minimum Clearance 6.7m

Minimum Clearance 5.2m

Fig.5 - Showing the Minimum clearance required on both Low, Medium and High Voltage Overhead Electricity Lines.





PART TWO

• danger notices should be installed which give a clear

indication of the working height and instructions given to

plant drivers to lower crane jibs, to tip bodies of lorries,

etc., and to drive carefully.(see Fig.7)

6.6.3 sites where work will be done under lines

• additional precautions are necessary where work must be carried out under overhead

lines and in each case early consultation with A.D.W.E.A is necessary.

• A.D.W.E.A. will advise on safe working clearances and all plant, equipment or hand tools

to be used must be of such construction or be so restricted that these safe working limits

cannot be exceeded. In extreme cases it is usually possible for the Department to make

the line dead for certain periods of time so that work can proceed.

6m Absolute minimum 10m Maximum

Advance Warning Sign

Between 3 – 6m

Height to be specified by A.D.W.E.A.

Traffic Passing Beneath Overhead Power Lines

Note: If any work takes place after dark, notices and cross bar should be illuminated.

Fig.6 - Showing various safe heights required for traffic to safely pass under Overhead Power Lines.

Fig.7 - Showing type of approved sign used to indicate presence of overhead lines.

SECTION 7

SECTION 7

ELECTRICITY AT WORK

INTRODUCTION 1


INTERNATIONAL STANDARDS

7.1 DUTIES 2

7.2 SUPPLIES 2

7.3 OPERATION AND MAINTENANCE 5

7.4 PLUGS, SOCKET-OUTLETS, COUPLERS 6

7.5 EQUIPMENT EARTHING (PROTECTIVE CONDUCTORS) RCD 7

7.6 SYSTEM VOLTAGE 8

7.7 CABLES 9

7.8 PLANT AND TOOLS 10

7.9 LIGHTING 11



PART TWO


ADM/H&S/Pt 2 01 March 2005 ELECTRICITY AT WORK 1 of 14

SECTION 7

ELECTRICITY AT WORK

INTRODUCTION

The use of electrical energy to assist in the construction process is extensive. The misuse or

malfunction of electrical equipment could have harmful effects on people and plant, but electricity is

perfectly safe if treated with respect.

This section is aimed to assist site managers, safety advisors and people in similar positions to satisfy

themselves that necessary steps are taken to ensure that electrical installations are safe.


Government of Abu Dhabi Water & Electricity Authority (ADWEA)

Regulations for Electrical Installation Works (1980)


BS 7671 : Requirements for electrical installations

(Formerly the IEE Wiring Regulations Sixteenth Edition)

BS 4343 : Industrial plugs, socket outlets and couplers for AC and DC supplies.

BS 4363 : Specification for distribution units for electricity supplies for construction and building

sites.

BS 7375 : Code of Practice for distribution of electricity on construction and building sites

BS 7430 : Code of Practice for earthing



PART TWO



7.1 DUTIES

7.1.1 consultants

The consultant engineering company shall ensure that:-

• the necessary and appropriate approvals are given for a selected electrical contractor or

sub contractor.

• the fixed and temporary ‘Electrical Distribution System’ and utilisation of ‘Electrical

Energy’ required for the construction phase of the contract complies and is operated

within the requirements of this section.

7.1.2 contractor

The Contractor shall ensure that:-

• both the fixed and temporary ‘Electrical Distribution System’ is designed with due

consideration of its purpose, external influences, compatibility of equipment and

maintainability of equipment used.

• they appoint, in accordance with ADWEA regulations, a ‘Competent Person’ who shall be

responsible for the installation, its use and modification during the construction phase of

the contract. The name of the designated person shall be prominently and permanently

displayed close to the main switch or circuit breaker controlling the installation.

• appropriate ‘Electrical Safety and First Aid’ signs are displayed.

7.2 SUPPLIES

7.2.1 incoming supplies

In making an assessment of the incoming supply requirements due consideration shall be

given to the size and locations of electrical loads and the manner in which they vary with

time during the project.

Ample allowance should be made in respect of welfare facilities. It should be noted that in

practice the air conditioning plant, heaters, drying room heaters, water heaters and canteen

cooking equipment, tend to be in continuous use. The use of thermostats, time or light

sensitive switches should be considered.

On large sites, allowance has to be made for the use of large items of equipment, e.g. tower

cranes. Where the load is sizeable or where there are special problems, such as remote

locations or large site areas, early and detailed planning of the site electrical system will be

necessary.

For large and complex installations, design and circuit drawings should be prepared,

showing the type and location of equipment.



PART TWO



When this estimated load is known, a decision as to how the supply is to be obtained may

be made. The options being from the Public Utility or where such a supply cannot be

obtained or where perhaps such a supply would be uneconomical, the only alternative is to

generate the electricity locally on site.

7.2.2 temporary supplies

Distribution of electricity on site is essentially quite different from a permanent installation.

There is constant need for convenient means of connecting plant which operates on a

variety of voltages, phases and currents in different places at different times. Load

requirements vary considerably. (see Fig.1)

FIG. 1 - Shows a Site Electricity Distribution Scheme designed to I.E.E.Standards. Note: All equipment specified in B.S. 4363 includes provision for major switches to be

locked off.

Stand by

Generator

Site Incoming

Unit

Incoming

Supply

Main Distribution Unit

Fitted with 300mA

Earth Leakage Circuit Breakers

oooo

oooooo

Outlet Units

Outlet panel

fitted with 30mA- ELCB,s

Outlet panel

fitted with 30mA- ELCB,s

oooo

ooo

Compressor

Tower Crane

Accommodation

Extension

Outlet Units

Festoon Lighting

Portable

Tools

Outlet

Units

Batching

Plant

Tower

Flood

Lighting



PART TWO



Wiring problems can arise because runs require re-routing or extension. Site conditions

themselves are scarcely conducive to planning a safe distribution system and the long

flexible cables for portable tools and lighting only make the overall situation the more

hazardous. Control gear may need to be portable thus its siting should be carefully planned.

7.2.3 unit distribution problems

In light of the less hazardous situations arising from the use of reduced voltage, a unit

distribution system has been evolved which is efficient, safe, flexible and economic for all

site work. It provides for the control and distribution of electricity from a main AC supply of

415 V (3-phase: 4 wire) and incorporates:-

• protection for the heavier electrical gear (415V: 3-phase) by using monitored earth

systems with or without sensitive earth – leakage circuit breakers.

• Reduced voltage (single – and three – phase) facilities for safety and flexibility with

portable tools and lighting. BS EN6039, 4363, 5486 & 7375 cover the technical

specifications for plugs, socket outlets, distribution units etc.

It should be stressed that this system is for site work only. Stores, site offices, canteens,

drying rooms etc. should be regarded as standard installations at normal mains voltage

(230V: 1 – phase) and conform to BS 7671.

Note: It is strongly recommended that this system be adopted for all site work and that a

clause requiring its use be included in all contract specifications.

7.2.4 main earthing terminal

Due consideration shall be given to the following earthing requirements:

• it is the responsibility of the consumer to provide and maintain an effective means of

earthing, the public utility regulations stipulates earthing electrodes.

• shall be driven to depth such that it penetrates the summer water table by a minimum of

2 metres.

• the resistance of any point in the earth continuity system shall not exceed 0.5 ohms.

• where the incoming supply is from the public utility and emergency standby generation is

also provided, then the supplies shall be mechanically and electrically interlocked so as

to ensure only one incoming supply can be switched into use.

7.2.5 existing services

Existing electrical installations will often be present on the site before the contract

commences, in the form of overhead lines, or underground cables. A survey should always

be conducted before work commences to determine the position and nature of such

installations and the results recorded and kept on site. The electricity supplier should

always be contacted for help and advice. (see Pt 2 section 6) for further advice on

Overhead/Underground cables.

Note: No work must be carried out on any live cable, or so near as to cause danger, unless

it is not practicable to make the cable dead and all necessary precautions are taken to

ensure safety.



PART TWO



7.3 OPERATION AND MAINTENANCE

7.3.1 maintenance

All electrical systems (which include all constituent parts) must be properly maintained to

ensure safety. Thus, inspection, tests and maintenance must be carried out on a routine

basis.

in addition to an initial inspection and test:

• fixed installations must be inspected and tested at least at three monthly intervals, routine

maintenance being carried out in accordance with equipment manufacturers’

recommendations.

• moveable and portable/transportable electrical equipment (as defined in BS 7671) should

be inspected, tested and maintained on a routine basis, depending on the use and

application of the particular item.

• records of training, permits-to-work, inspection, testing and maintenance should be kept

throughout the working life of an electrical system. In addition, records of circuit

diagrams, cable runs, loading diagrams and other relevant information should be retained

and kept up to date.

7.3.2 instruction, training and supervision

The installation, operation, maintenance and testing of electrical systems and equipment

should be carried out only by persons who are competent for the particular class of work.

Where employees’ knowledge or experience is not sufficient, adequate supervision must be

provided. The responsibilities of supervisors should be clearly detailed by relevant duty

holders.

7.3.3 first aid

Notices should be posted which give advice on treatment in the event of an electric shock

and there should be adequate provision for calling the emergency services. (see pt 2

section 10) – Safety Signage.

Speed is essential in dealing with any electrical accident and all electricians should be

familiar with action to be taken in an emergency.

7.3.4 testing and commissioning

All completed electrical installations must be inspected, tested and commissioned before

being made available for use. The inspection and tests necessary are listed in IEE Wiring

Regulations, but the construction site user should satisfy himself that the tests have been

carried out.

Written certificates should be completed for these tests.



PART TWO



7.4 PLUGS, SOCKET-OUTLETS AND COUPLERS

For distribution of electrical energy cable Plugs, socket-outlets and couplers for AC and DC

supplies are readily available to BS 4343 specifications

The BS specification covers single and three-phase components, a safeguard being

incorporated so that electrical apparatus operating at one voltage cannot be plugged into the

wrong supply. This is achieved by setting the earth point of plugs and socket-outlets at a

different “hour” position for each voltage and having a key (plug) and key-way (socket-outlet)

at a standard 6 o’clock position, so that they can only fit one way.

Plugs and sockets are available in a variety of designs providing varying degrees of

protection against damage and weather. The two types most commonly used on construc-

tion sites are the “splashproof” and the better “waterproof” designs. (see Figs. 2,3,4 & 5)

Fig.2 - Plugs with splash proof spring return covers:

110/130V

220/240V

Fig.4 - Plugs fitted with central water tight cable gland and strain relief clamp for mechanical support

Fig.3 - Free plugs – straight incorporating external cable grommet which allows water to run off the back of the plug.

Fig.5 - Angled panel sockets which allow for easier insertion and extraction when used on vertical surfaces.

Note: Distribution of electrical energy to moveable equipment shall only be permitted where such plugs and sockets are used.



PART TWO



7.5 EQUIPMENT EARTHING (PROTECTIVE CONDUCTORS) ELCB

There is always the risk of shock, fire, or burns if electrical insulation deteriorates or is

damaged and there is leakage of current. It is therefore usual practice to earth all metalwork

which could be made live by such leakage.

On all building sites where temporary electricity supplies are required voltage operated earth

leakage circuit breakers shall be installed and shall be arranged to have the operating coil

connected between the consumers earthing terminal and the main earth electrode with

insulated connecting leads.

Additional residual current earth leakage circuit breakers should be fitted on the advice of

the duty holder. In particular, BS 7671 requires the fitting of residual current device

protection for socket outlets used to supply portable equipment outdoors. However, it is

emphasised that such devices, in themselves, do not provide complete protection against

shock.

All extraneous metalwork and exposed conductive parts should be bonded together and

connected to the system’s main earth terminal. Circuit protective conductors must be

installed to provide the return path from each outlet of an installation to the main earthing

terminal.

protective conductors comprise

• part of a cable or flexible cord,

• the armour, or metal sheath of a cable,

Reduced voltage provides increased protection against shock, but its effectiveness depends

upon the transformer being correctly earthed and this must not be overlooked.

Figs. 6,7,& 8 showing typical examples of RCD protected sockets and adaptors:

Fig.6 - RCD protected outlet

plug.

Fig.7 - Metal Clad RCD Sockets.

Fig.8 - 13 amp RCD Adaptors

• conduit, trunking, ductng or parts of

enclosures designed for the purpose.



PART TWO



7.6 SYSTEM VOLTAGE

Ideally, the most acceptable reduced voltage compromise for site work (including portable

tools and lighting) is 110 V, single-or three phase, so that no part of the installation is at

more than 55 V or 65 V respectively to earth, but appreciating that , especially for the smaller

Contractors, this may not be practicable due to availability and cost, the use of 240v is

acceptable providing the requirements of section 9.5 Earth Leakage Circuit Breakers

(ELCB), and section 9.8 Plant & Tools are fully adhered to.

recommended distribution voltages

Fixed and moveable plant

above 3.75 kW 415 V: 3 phase

Fixed floodlights 240 V: 1 phase

Small mobile plant up to 3.75 kW 110 V: 3 phase or 240v with ELCB Protection

Portable handlamps (general use) 110 V: 1 phase or 240v with ELCB Protection

Portable hand-held tools 110 V: 1 phase or 240v with ELCB Protection

Local lighting up to 2 kW 110 V: 1 phase or 240v with ELCB Protection

obtaining reduced voltages

Where it is practicable to use 110v, the following is the correct method to be used for

achieving this:-

110 V 3-phase

• using a double-wound transformer with the neutral point of its star-connected secondary

winding earthed so that the nominal voltage to earth is approximately 65 V.

110V 1-phase

• using a double-wound transformer with the centre tap of the secondary winding earthed

so that the nominal voltage to earth is 55 V.

110 V 3-phase

• using portable generator set properly or 1-phase earthed in accordance with BS 7375.

7.6.1 identification colours

The use of the following colour coded cables should be adopted for distribution:

operating voltage AC colour

25 Violet

50 White

110 Yellow

220/240 Blue

380/415 Red

500/650 Black

Where Applicable



PART TWO



7.7 CABLES

For all site offices, workshops, huts, drying rooms and similar premises which are regarded

as permanent type installations, BS 7671 must be adhered to. For general site work

additional precautions are necessary.

Other than supplies for welding purposes, cables carrying a voltage to earth in excess of

65V should have continuous metal armour or sheath which has been effectively earthed.

Where. trailing cables are concerned, this earthing should be in addition to the normal cable

protective conductor.

In view of the rough conditions on site, all cables should be sheathed overall.

7.7.1 main types of cable sheaths

TRS (tough rubber sheath)

good mechanical properties; resistant to wear and abrasion; unable to withstand solvents or

oil.

PVC (polyvinyl chloride)

unsuitable for outside work where low temperatures are to be expected, but permissible for

site offices and similar permanent work.

PCP (polychloroprene)

combines the advantages of TRS and PVC, i.e. resists wear and abrasion; withstands

solvents, oil, etc.

Cables buried directly in the ground shall be of a type incorporating an armour or metal

sheath or both or be of the PVC insulated concentric type. Such cables shall be marked by

cable covers or a suitable marking tape and be buried at a sufficient depth to avoid their

being damaged by any disturbance of the ground. Cable routes should be marked on the

plans kept in the site electrical register.

Low and medium voltage cables often have to be suspended and some type of bold marking

or “goal post” arrangement of non-conductive material should be erected to indicate their

presence. Where these cables need to cross open areas, or where spans of 3m or more are

involved, a catenary wire on poles or other supports will provide a convenient means of

suspension. Minimum height should be 6m above ground.

It is sometimes necessary, because of the nature or circumstances of a particular job, for

cables to lie on the ground, if only for a short time. In such cases, additional protection

should be provided by means of a conduit and special provisions made if vehicles have to

cross (e.g. ramps). The line should be clearly marked.

Joints in cables should be avoided wherever possible. Where unavoidable, they should be

enclosed in purpose-built housings.



PART TWO



7.8 PLANTS AND TOOLS

7.8.1 plants

A large proportion of plant in use on site is electrically driven. Particular attention should be

paid to its positioning and to its supply leads.

fixed plant

(415 V: 3-phase), e.g. tower cranes, large hoists, continuous batch mixers, etc. Siting should

be carefully planned so that they can remain in one position throughout the job and so that

supply cables, of sufficient capacity, can be routed clear of construction work and be

protected against traffic movement.

movable plant

With load in excess of the 110 V: 3-phase system capacity, e.g. compressors (415 V: 3-

phase). The earth conductor in the heavy trailing supply cable must remain unimpaired if the

plant is to be used safely. If it is broken, current cannot flow to earth if a fault occurs, and it is

therefore strongly recommended that earth monitoring and/or a residual current operated

circuit breaker is provided.

7.8.2 light movable plant and portable tools

(110 V: 1- or 3-phase) or, 240v. supply panel fitted with a 30mA ELCB - e.g. drills, sanders,

polishers, grinders, vibrators, paint sprayers, soldering irons, etc.

supply leads

to these tools are likely to be lengthy; every effort should be made to protect them from

damage. Tools should be disconnected before any adjustments are made or attachments

changed.

portable tools

for use on high frequencies (in excess of 50 Hz) need a supply from a special generator and

manufacturer’s instructions should be consulted before any connections are made.

certified (kite-marked)

double-insulated or all-insulated tools may be used without earthing (i.e. with two core

cables), but they should still be used only if power supply unit is either protected by Earth

Leakage Breakers, or the portable tool itself is fitted with a 13amp. RCD plug.

Where tools have to be used away from the supply plant, an OU (outlet unit) or EOU

(extension outlet unit) should be used.

7.8.3 maintenance of plant and tools

In view of the risks from damaged or faulty electrical equipment, an appropriate maintenance

system should be set up. It is also important that equipment is regularly serviced in

accordance with manufacturers’ instructions.



PART TWO



• the cable covering is gripped where it enters

the plug or equipment,

• the outer casing of the equipment is not

damaged or loose

• there are no signs of overheating on the plug,

Visual checks should be carried out daily by users and formal inspections should be carried

out by competent persons at regular intervals.

These checks and inspections should ensure that:-

• bare wires are not visible,

• the cable covering is not damaged,

• the plug is in good condition,

• there are no taped or other non-

standard joints in the cable,

Residual Current Devices (RCD’s) should be checked to ensure they are working correctly

(the test button should be pressed daily).

Testing, by a competent person can detect faults such as loss of earth continuity,

deterioration of the insulation and internal or external contamination by dust, water, etc.

Note: The practice of connecting portable tools or any other type of electrical apparatus by

inserting bare wires into a distribution board or socket, is strictly forbidden.

7.9 LIGHTING

As well as supplementing poor daylight and enabling work to continue after dark, site lighting

is always necessary if in those areas are devoid of natural light, e.g. shafts and enclosed

stairways. Apart from permitting men to see what they are doing, adequate lighting helps to

minimise physical hazards; it facilitates the delivery and movement of material after dark; it is

an effective deterrent to intruders, pilferers and vandals. In short it safeguards men,

equipment and materials and makes for efficient, economic production.

Site lighting must be sufficient, well planned, of the right type and in the right place for it to

be properly effective. Lighting ought not to introduce the risk of electric shock.

7.9.1 measuring illumination level

Illumination levels on any part of a site can easily be checked with a pocket lightmeter,

calibrated in lux. These meters should be checked periodically and be kept covered when

not in use.

7.9.2 level of illumination

The unit of measurement for levels of illumination is the lux. One lux equals one lumen of

light falling on one square metre (lm/m2).

The level of illumination required to provide conditions in which work can be carried out

without undue risk or fatigue should not be less than the figures shown below. The figures

quoted take into account the effect of dust and dirt, depreciation, low contrast areas, etc.



PART TWO



Recommended minimum levels of illumination:

Interior movement only 5 lux

General movement 5 lux

Handling materials, unloading 10 lux

Exterior general 10 lux

Clearing sites, general rough work 15 lux

Interior working places 15 lux

Interior reinforcing and concreting 50 lux

Bricklaying (except facings), 100 lux

Bench work, facing brickwork and plastering 200 lux

Interior workshops 400 Iux

Drawing boards 600 lux

The term interior lighting covers those parts of structures which may not have cladding

during erection, but which will become interiors when the work is finished.

7.9.3 area lighting

The object of area lighting should be to produce an overall level of illumination sufficient for

men and vehicles to move about in safety. Every part of the area should receive light from at

least two directions to avoid dangerous, dense shadows.

Luminaires of the area lighting type should be mounted on poles, towers, or static crane

towers. Moving supports, e.g travelling cranes, are quite unsuitable since they cause lamps

to cast dangerously deceptive moving shadows.

If luminaires are spaced too widely, illumination becomes patchy, confusing and ineffective.

Luminaires of the non-symmetrical type should be spaced at not more than three times the

mounting height. Other area luminaires should be spaced at not more than 1.5 times the

mounting height.

7.9.4 beam flood lighting

Beam floodlights are used to throw concentrated light over an area from a relatively great

distance. The beam may be conical or fan-shaped and a ribbed spreader glass is sometimes

fitted to widen the beam in one plane.

Floodlight beams are usually classified according to their spread - wide, medium or narrow -

and it should be noted that performance changes radically with size and type of lamp. A

flood that gives a medium spread with a GLS lamp can give a wide spread with an MBF

lamp.

Narrow beam floodlights are only used on sites with large open group areas and they are

usually mounted in clusters on temporary towers at least 30m high.



PART TWO



With narrow beam luminaires there is always a hazard from glare because the beams are

intense. To minimise glare, they should be mounted as high as possible and the beams

should be directed downwards on the work.

significant points:

• the area illuminated decreases and the level of illumination increases as the floodlight is

brought closer to the work on the basis of the “inverse square rule”;

• to increase or decrease the level of illumination, floodlights should be moved closer to, or

further from the work — or their power should be changed;

• beam floodlights are often used to raise the light level at the point of work. (Sufficient light

should reach the workpoint from at least two directions to avoid creating shadow

hazards).

Figs. 9 & 10 show typical examples of Beam Flood Lighting lamps available.

7.9.5 dispersive lighting

Dispersive luminaires are similar to

industrial indoor types, but are

weatherproof and protected against

corrosion. They are used wherever

they can be suspended over the area

to be illuminated.

Luminaires should be spaced to

provide an even spread of light; the

ratio of spacing to mounting height is

usually 1.5:1 There are also

recommended minimum heights,

according to the lamp which must be

observed. (see Fig.11)

Fig.10 - Metal Halide - Environmentally protected

Fig.9 - High Pressure Sodium Lamps.

Fig.11 - Portable Site lighting attached to mobile Generators



PART TWO



7.9.6 walkway lighting

• includes stairs, ladderways, corridors, scaffold access routes and the localised

illumination of what would otherwise be small shadow areas, which could in themselves

be dangerous.

• luminaires are of the well glass or bulkhead type: when fitted with red lamps or red or

orange glasses, these types are widely used to delineate danger areas -hales,

excavations, obstructions, etc.

• If practicable, 11OV supply should be used for regular site work, e.g. on scaffolding and

other temporary structures, because both fittings and cables are prone to damage. A

230V supply should only be used where luminaires and cables are properly fixed, well

protected and supply protected with Earth Leakage Breakers.

• mounting should be as high as possible to avoid glare.

• spacing should be such that the light is evenly spread.

• sufficient light for access purposes on a scaffold platform 1 -1 .5 m wide can be obtained

from walkway luminaires using 60 watt Filament amps or two B waif fluorescent tubes,

set 2.5m - 3m above the walkway and not more than 6 m apart.

• mounting centrally above the walkway is to be preferred.

7.9.7 local lighting

This group covers the most widely used forms of lighting on sites, and since these fittings

are generally accessible to operatives, it is most important that they are either connected to

a 110v supply, or if 230v used, and supply protected with Earth Leakage Breakers.

Tungsten Filament lamps provide the most convenient forms of local lighting, but these

lamps, being relatively small sources of light, tend to produce hard shadows. Therefore, they

should be used with diffusers, or strung in a row so that each bulb in turn softens the

shadows created by the bulb on either side of it.

All lamps required for this type of work should be in waterproof lampholders and be

protected by guards or shades. Local lighting at the work point should supplement the

general Lighting scheme.

Luminaires should always be placed so that no person is required to work in their own

shadow and so that the local light for one person is not a source of glare for the next.

Great care should be taken that local light reaches the work from the same general direction

as light will come from window or permanent fitment when the job is finished. By doing so,

blemishes that would show up badly in the final lighting can be avoided.

Pendant luminaires should be supported so that the supply cable is not required to bear any

weight. Festoon lighting is an exception but, in this connection, only the type which uses

moulded-on lampholders is to be recommended.

SAFETY CHECKLIST - MANUAL HANDLING & LIFTING

Document No. Rev Date Title Checklist

ADM/H&S/CL/2.08/1 01 March 2005 SAFETY CHECKLIST - MANUAL HANDLING & LIFTING 1 of 1

Preparation

�� what is being lifted?

�� where to and how far?

�� how many people are needed?

�� are they trained in kinetic lifting and handling?

�� what methods and equipment are required?

�� is equipment required available?

�� would mechanical means be more practicable?

�� is the lifting and handling area clear of hazards?

�� is the operation part of a routine. If so, could it be more effectively planned and executed?

Lifting and handling

�� protective clothing in use?

�� proper (kinetic) method being employed?

�� co-ordination satisfactory in dual and team lifting?

�� necessary equipment in use or to hand?

�� are excessively heavy weights being lifted?

�� are loads being deposited/stacked safely and securely?

�� adequate supervision employed where necessary?

After lifting and handling

�� any incidents/accidents should be reported and recorded?

�� where injuries sustained, has medical attention been sought?

�� damage or loss of equipment etc., recorded?

SECTION 9

SECTION 9

HIGHLY FLAMMABLE LIQUIDS & LIQUEFIED PETROLEUM GASES INTRODUCTION 1

DEFINITION

MAIN APPLICABLE U.A.E LEGISLATION

9.1 HIGHLY FLAMMABLE LIQUIDS 2

9.1.1 storage 2

9.1.2 fire 3

9.1.3 handling of highly flammable liquids 3

9.1.4 empty containers and tanks 4

9.1.5 use of highly flammable liquids 4

9.1.6 spraying of highly flammable liquids 5

9.1.7 petroleum based adhesives 5

9.2 LIQUEFIED PETROLEUM GAS 6

9.2.1 characteristics and hazards 6

9.2.2 refillable cylinders 6

9.2.3 transportation 7

9.2.4 use of LPG in cylinders 7

9.2.5 general precautions 7

HIGHLY FLAMMABLE LIQUIDS & LIQUEFIED PETROLEUM GASES SAFETY CHECKLIST

(ADM/H&S/CL/2.9/1)



PART TWO


ADM/H&S/Pt 2 01 March 2005 HIGHLY FLAMMABLE LIQUIDS & LIQUEFIED PRETROLEM GASES 1 of 10

SECTION 9

HIGHLY FLAMMABLE LIQUIDS & LIQUEFIED PETROLEUM GASES

INTRODUCTION

Both highly flammable liquids (HFL) and liquefied petroleum gas (LPG) are widely used in building site

processes and operations. The principle hazard associated with both is fire, and it is essential that

precautions are taken to limit the risk involved.

Broadly speaking in dealing with both substances safety may be divided into three aspects:

• Storage

• Handling/transport

• Use

DEFINITION

Highly Flammable Liquid means any liquid, liquid solution, emulsion or suspension which when tested:

(a) gives off a flammable vapour at a temperature of less than 32°c.

(b) supports combustion.

Liquefied Petroleum Gas means commercial butane, commercial propane or any mixture thereof.


Ministerial Order No. (32) Year 1982 - Article (9)



PART TWO



9.1 HIGHLY FLAMMABLE LIQUIDS (HFL)

9.1.1 storage

On building sites, highly flammable liquids are not normally stored in fixed tanks. The following

details relate to the facilities necessary for safe storage of adhesives, paint, solvents etc. in

drums and cylinders up to 225 litres (50 gals’) capacity.

in open air

• the store should be formed on a concrete paving or

other impervious surface. A low sill ramp greater

than 150mm, should surround the paving at a height

sufficient to contain the maximum contents of the

largest drum stored. The paving should be bounded

by wire mesh fencing with access to the storage

area by way of a ramp over the sill. (see Fig.1)

• containers should be protected from direct sunlight by a roof of light fire resistant material. The distance between the store and any adjacent building, workplace or boundary fence should not be less than 4m.

• drums should be stored so that their contents can be

identified and where, in the event of leakage, they are

accessible for removal.

• gangways should be of sufficient width to allow easy

handling.

• the store should be marked ‘Highly Flammable’ or specify

flammability, e.g. ‘Flashpoint below 32°C, in clear bold

letters. (see Fig.2). Where this is impracticable, display ‘Highly Flammable Liquids’ sign as near to store as possible.

• naked flames, smoking or means of ignition should be

prohibited in the area of the store. Lighting should be of the

approved flameproof type.

• portable fire extinguishers of the dry powder or vaporising

liquids (BCF) type should be sited at strategic positions in, or

adjacent to the store as necessary.

Fig.1 - Open air Storage cage with fire resistant roof, lockable doors, segregated storage area for empty and full cylinders.

Fig.2 – Approved Sign for an LPG Store.



PART TWO



inside buildings

• a separate building should normally be provided and used solely for the storage of highly

flammable liquids where security and protection from weather is required. Such a building

need not be constructed of a fire resisting material.

• It should be located in a safe position, i.e. the distance between the outside wall of the store

and any adjacent buildings or boundary fence should not be less than 4m. Should space be

insufficient to isolate the store in this way, wall/partitioning must constructed with a fire

resisting material.

• rooms in finished buildings are generally unsuitable for use as storerooms.

additional points

• adequate ventilation of the store should be achieved by louvers or grilles. Care should be

taken not to obstruct these vents by stacked drums.

• a sill,no greater than 150mm should be provided at each door opening to prevent the outflow

of spilled flammable liquid.

• store should be marked ‘Highly Flammable’, or flammability specified, e.g. ‘Flash point below

32oC’, in clear bold letters.

• naked flames, smoking or means of ignition should be prohibited in the area. Lighting

should be of the approved flameproof type.

• portable fire extinguishers of the dry powder or vaporising liquids (BCF) type should be sited

at strategic positions adjacent to the store as necessary.

• where the quantity of highly flammable liquid to be stored is not more than 50 litres (10 gals)

it may be stored in the workplace, in a suitable cupboard or bin of fire resisting structure.

9.1.2 fire

For small fires involving highly flammable liquids Foam (AFFF) portable fire extinguishers are

preferable. Dry powder should only be used in the absence of Foam - especially if the liquid is

flowing; when the liquid is contained (as in a drip tray) CO2 extinguishers also suitable, but is

best used in covered areas preferably by trained personnel.

You should note that the efficiency of the external use of CO2 is severely restricted because it

gets quickly dispersed with the wind.

Note: Water must never be used to extinguish fire involving flammable liquids.

9.1.3 handling of highly flammable liquids

• bulk delivery of HFL should be made directly into the store and not off-loaded and left till

removed to the store.



PART TWO



• decanting of HFL should be carried out either in the open air or in a separate room of fire

resisting construction. Containers should be checked for leaks, sealed or contents

transferred as necessary. Small ready-to-use containers should be marked ‘Highly

Flammable’ and capped. A number of companies supply special drums, containers, taps

and drip trays, especially designed for HFL, incorporating spring loaded caps and spouts

etc. (see Fig.3) funnels should be used to minimise spillage and trays to contain any

unavoidable spillage.

• filling of small containers from larger drums should not be carried out in the store but in a well-ventilated place, preferably in the open air. Small containers should be marked ‘Highly Flammable’ and fitted with an effective cap. Where applicable, cans should be fitted with pouring nozzle with spring-loaded closure cap.

• spillage should be soaked up with non-combustible

absorbents or sand, which should be disposed of

safely.

9.1.4 empty containers and tanks

• heat must not be applied to, nor any attempt be made to cut or section empty containers.

They may explode.

• special care is necessary when the demolition or dismantling of tanks is undertaken as

disturbing or heating solid residues remaining in them may cause hazardous concentrations

of flammable vapours. Entry into tanks requires a certificate written and signed by a

responsible technical specialist.

9.1.5 use of highly flammable liquids

• heavy concentrations of vapour arising from the use of HFL should be avoided if possible,

and dispersed using natural or mechanical ventilation. If it is necessary to employ a

mechanical extraction system, a flameproof electrical motor should be used to avoid risk of

explosion.

• in general, where work involves the use of HFL inside a room or confined space, the power

supply should be cut off. Any space-heating appliance provided must either be sited remote

from any flammable vapour source or be incapable of causing ignition.

• naked flames, welding, heating torches, cigarettes, etc. should be prohibited in an area

when HFL vapour is present.

• metal bins with lids should be provided for off cuts, waste material and cleaning rags

contaminated with HFL, and should be emptied frequently.

Fig.3 - Type of Drip tray used for de-canting flammable liquids.



PART TWO



• HFL or toxic solvents should never be used to wash hands, floors or surfaces. Use

detergent degreaser cleaner.

• if brushes and scrapers require soaking, use suitable container with lid.

9.1.6 spraying of highly flammable liquids

Care should be exercised in:

• identifying the material in use and observing the manufacturer’s recommendations for use

and safety.

• selecting the correct type of spraying equipment. Spray booths with both appropriate and

approved exhaust ventilation should be used.

• providing personnel with protective clothing, respiratory equipment, hygiene and cleansing

facilities.

• avoiding the introduction of sources of ignition into working areas, i.e. non-flameproof

electrical equipment, combustion engines, hand tools, heating equipment, cigarettes, or

anything which might cause sparks.

• providing warning notices at entrances and physical barriers where necessary.

• controlling, storing and decanting material.

• providing fire-fighting equipment.

9.1.7 petroleum based adhesives

With the development of plaster and similar type boards used as coverings to walls and ceilings

and tiles for floors and other areas, the use of petroleum based adhesives in fixing is becoming

widespread.

Dangers arise from these materials, particularly when used in poorly ventilated areas where

concentrations of vapours are allowed to accumulate. Ignition of the vapours by a spark, e.g.

the simple action of switching on a light, may result in an explosion or fire, therefore the

following precautions should be observed:

• identify adhesive, its flash point and manufacturers recommendations for use and safety.

• open doors and windows; provide mechanical exhaust ventilation where necessary.

• when fixing floor coverings with highly flammable adhesives, treat only small areas at a time

and work towards door from further point.

• provide protective clothing and respiratory equipment as necessary.

• provide fire-fighting equipment.

• avoid introducing sources of ignition into work areas, e.g. cigarettes, hand tools, combustion

engines, heating equipment producing naked flames. Electrical equipment and fittings

should be of suitable flameproof design, or be isolated by removal of fuses.



PART TWO



• provide warning notices at entrances to the area and, where necessary, barriers to prevent

unauthorised access.

Note: Where petroleum-based adhesives are in use and doubts exist as to the concentration

of flammable or explosive vapours, sampling equipment should be employed.

9.2 LIQUEFIED PETROLEUM GAS (LPG)

On building sites, LPG has numerous uses ranging from heating bitumen cauldrons and boilers,

site offices and huts, to use as a fuel to power hand tools and oxy-propane cutting equipment.

Properly used, LPG is a convenient and valuable source of energy. Carelessly used, it is

extremely dangerous.

9.2.1 characteristics and hazards

• LPG is colourless; its vapour is heavier than air, and if it leaks will sink and flow into drains,

excavations etc.

• leakage, especially of liquid, may release large volumes of highly flammable gases. One

cubic metre of liquid propane equals roughly 250 cubic metres of propane gas.

• a small, proportions of gas in air (for propane, between 2% and 10%) can give rise to an

explosive mixture. If present in a confined space and ignited, it will cause an explosion.

• because LPG vapour will sink and flow, any vapour/air mixture arising from leakage may be

ignited some distance from the point of leakage and the resulting flame travel back to the

point of leakage.

• LPG is normally odorised before distribution so as to enable detection by smell.

• leakage may be noticed by smell or the cooling effect on the air at the point of leakage

causing condensation. Leaks should not be traced using a lighted match or naked flame.

Use soapy water.

• in contact with skin, the liquid will cause severe frost burns.

• though non-toxic, it is an asphyxiate and an anaesthetic.

9.2.2 refillable cylinders

• a store for refillable cylinders should be located away from site boundaries, enclosed

buildings, fixed sources of ignition and electrical equipment, in accordance with the following

table of weights/distances.

KGs Distance in

metres

50-300 1



PART TWO



300-1000 2

1000-4000 4

• a base should be compacted or paved, and enclosed by a fence minimum of 2m high.

• cylinders should be protected from direct sunlight by a roof of light, fire resistant material.

• two exits should be formed (not adjacent to each other) with doors opening outwards and

not self locking.

• signs should be displayed indicating the presence of LPG and prohibiting smoking and

naked flames.

• the storage area should be kept free of weeds and grass. Sodium chlorate should not be

used for this purpose. Access/egress must be kept clear.

• cylinders should be stored with valves uppermost.

• LPG cylinders may be stored with other cylinders of flammable gases but should be

separated from oxygen, toxic or corrosive gases by a distance of 3m.

• stocks should be grouped by the 1000kg and groups separated by 1.5m gangways.

• LPG cylinders should not be stored within 3m of flammable liquids or combustible materials.

• cylinders must not be dropped during handling or brought into violent contact with other

cylinders, or adjacent objects.

• valves should be in the closed position, and valve caps fitted.

• where lighting is necessary, it should be mounted at least 4m above ground level and at

least 2m above the topmost cylinder of the stack.

9.2.3 transportation

When loaded on vehicles for transportation, cylinders, (whether full or empty), must be stood

upright and secured. Vehicles should have fire extinguishers (CO2 - dry powder) readily

available, should carry first aid packs, and display appropriate warning notices.

9.2.4 use of LPG in cylinders

All personnel responsible for the storage of LPG should understand the characteristics of the

product. They should be familiar with the fundamentals of fire fighting and control and aware of

the procedures in force for dealing with such emergencies.

It is difficult to cover all aspects of the use and application of LPG; following list of points should

not be regarded as exhaustive.

9.2.5 general precautions



PART TWO



• before and after use, valve protection caps and plastic thread caps/plugs should be fitted to

minimise damage.

• cylinders should be kept upright and care should be taken during handling.

• full and empty cylinders should remain separated. Valves should be left in closed position

when not in use.

• never place cylinders below ground level, since any leakage of gas will not disperse.

• regulators should be handled with care and the hose

and connections should be examined before fitting.

All LPG containers are fitted with left hand thread

connections. Union nuts and couples have grooves

on the outside corners of the nut confirming left-

hand thread. Use correct size spanner. (see Fig.4)

• flexible hoses should be in good condition and

be protected, or steel braided if likely to be

subjected to damage by abrasion. (see Fig.5)

• over tightening connections will damage threads

and may cause leaks. Checks should be carried

out by smell-or use soapy water.

• weekly inspections should be carried out on LPG

appliances and equipment. Checklist should cover

testing for leaks, cleaning, adjusting, checking

hoses, hose clips and ferrules. (see checklist at

the end of this section).

bitumen boiler and cauldrons

• the gas cylinder should always be positioned at least 3m away from the boiler or cauldron.

• full cylinders, not connected, should be kept at least 6m away from appliance. Full cylinders

awaiting use should be kept out of direct sunlight.

• supply hoses should be checked for crushing, damage to metal braiding and impregnation

by bitumen. Unserviceable hoses should be replaced.

• if frost forms on outside of cylinder, flow rate is excessive. Avoid by using two or more

cylinders and a manifold or, if possible, a smaller burner.

blow torches, roofing irons

• lash cylinder to prevent it falling on its side when pulled.

Fig.4 - Typical type of Regulator fitted to most LPG Containers used on Building Sites.

Fig.5 - Flexible High Pressure steel braided hose with non return valve connection.



PART TWO



• a suitable high-pressure hose should be used and inspected frequently for wear.

• manufacturer’s recommended operating pressure should be observed.



PART TWO



site huttage

• cylinders and regulators should be fixed outside the building and the supply taken in at low

pressure via rigid pipe (copper or iron), with a flexible connection to the appliance.

• flexible tubing should be limited to a maximum length of 2.438m.

• pipework should be exposed and easily accessible for checking.

• appliances designed for use outside and requiring high ventilation should not be used within

huts.

• ventilation for convector heaters and cookers should be both permanent and adequate.

• weekly inspections should be carried out if soot forms or smell occurs, the reasons should

be determined.

fire

Instructions for dealing with LPG in the event of fire may vary with given situations. However, in

an emergency, it is of paramount importance to avoid endangering human life.

the following action should be taken by persons discovering a fire:

• summon the Fire Services (civil defence department). Acquaint Fire Officer with location of

all cylinders.

• if it can be done safely, turn off all valves to cut fuel supply and remove cylinders from the

danger area. Where this is not practicable, cool by copious spraying of water.

• if cylinders are equipped with automatic relief valves and fire exposure is severe, it must be

remembered ignited gas jets from these valves can extend a considerable distance.

• if cylinders are exposed to severe fire conditions and engulfed in flame, no attempt should

be made to fight fire. In such conditions summon Civil Defence and evacuate the area.

• where flame from a leaking gas bottle is extinguished, but gas or vapour continues to

escape, there is danger of an explosive re-ignition.

• instructions concerning emergency procedures should be provided and displayed as

necessary. Employees should be trained in the use of fire fighting equipment.

fire extinguishers

• sufficient numbers of adequate size dry powder fire extinguishers should be available.

Foam extinguishers are only suitable for small internal LPG fires.

• extinguishers should be provided for all operations and locations involving LPG, ranging

from the use of hand tools to site huttage and bulk storage.



PART TWO



Note: As a guide to the requirements for the latter,

a minimum of 4.5kg (10lb) dry powder is

necessary for up to a total of 450kg (1000lb)

weight of LPG. For larger storage areas

consultation with the Civil Defence is

advised. (see Fig.6)

Fig.6 - Showing example of 4.5 kg Dry Powder Extinguisher suitable for fires involving LPG.

SAFETY CHECKLIST - H.F.L. & L.P.G.


ADM/H&S/CL/2.09/1 01 March 2005 SAFETY CHECKLIST - HFL & LPG 1 of 4

HIGHLY FLAMMABLE LIQUIDS (HFL)

General storage requirement

a) stores

�� mark ‘Highly Flammable’ - indicate flash point

�� access clear

�� fire extinguishers provided

b) storage in open air

�� concrete base

�� mesh fence

�� roof cover

�� sill and ramp

�� separation distance 4m

c) storage in building

�� used exclusively for HFL

�� sill at doorway

�� well ventilated


Workplace

�� 50 litres (10 gals) or less in fire resistant, marked bin/cupboard

Decanting

�� in open air or fire resistant building

�� into small marked containers with effective closure

�� funnels/trays used

�� spillage mopped up/sanded

�� absorbents disposed of safely

Use of Highly Flammable Liquids

�� good ventilation or mechanical extraction with flame proof motor

�� no naked flame or ignition sources

�� waste bins provided, with lids

�� warning notices displayed





HIGHLY FLAMMABLE LIQUIDS (HFL) continued…

�� containers with lids, for cleaning brushes etc.

Spraying

�� identify materials: observe precautions in use and storage

�� use correct equipment

�� protective equipment/clothing

�� avoid ignition risks

�� warning notices, barriers in use


Flammable adhesives

�� identify type of adhesive and check precautions for safe usage

�� use exhaust ventilation as necessary – spark free motors

�� use respiratory/protective clothing

�� no ignition sources; avoid sparks and naked flames

�� electrical installations – isolate fuses

�� provide warning notices: erect barriers

�� solvent not used to clean hands, surfaces etc.

�� empty containers not to be heated or cut.

�� tanks - precautions taken against risk of explosion

�� entry into tanks, authorising permit obtained first.

Fire Emergency Procedures

�� emergency procedures - provide and display instructions.

�� procedures practised

�� summon Civil Defence

�� fight fire, but do not endanger life




LIQUEFIED PETROLEUM GAS (LPG)

Storage

�� fixed/movable tanks - obtain specialist advice


�� compacted/paved base

�� mesh fence

�� fire resistant roofing

�� two exits - outward opening

�� warning signs displayed

�� weed free area - no sodium chlorate

�� access clear


�� cylinders stored upright

�� 3m from oxygen, corrosive or toxic gases

�� avoid violent contacts, dropping of cylinders

�� grouped by 1000kg - 1.5m gangways

�� lighting - 4m above ground, 2m clear of top most cylinder

Transportation

�� cylinders upright and secured

vehicle equipped with:

�� fire extinguishers

�� first aid

�� warning notices

Use of LPG Cylinders and Appliances

�� before and after use: valve in off position; fit valve caps/plugs

�� handle regulators carefully

�� avoid cross-threading/use correct spanner

�� inspect equipment weekly, hoses, clips etc. Test for leaks - use soapy water.




LIQUEFIED PETROLEUM GAS (LPG) continued…

Bitumen Boilers

�� cylinder - 3m from boiler (not in use - 6m)

�� protect from direct sunlight

�� inspect hose frequently

Hand tools

�� lash cylinders upright

�� check hose for wear

�� operate at recommended pressure

Huttage

�� cylinders outside building

�� rigid pipe in use and accessible for inspection.

�� maximum length of flexible tubing to appliance 2.438m

�� high-ventilation appliances; do not site in huttage

�� carry out weekly inspections

Fire Emergency Procedures

�� fire/emergency procedures: provide and display written instructions

�� do not endanger life

�� summon Civil Defence

�� fight fire with dry powder. Cool cylinders with water

�� turn off gas supply if safe to do so

�� if flames engulfing cylinders, do not fight fire

�� beware ignited gas jets from automatic relief valves

SECTION 10

SECTION 10

SAFETY SIGNAGE

INTRODUCTION 1


10.1 PROHIBITION 2

10.2 MANDATORY 3

10.3 WARNING 4

10.4 SAFE CONDITION 5

10.5 FIRE EQUIPMENT 6


10.7 DETERMINING SIGN SIZES 8

10.8 STANCHION SIGNS 8

10.9 SAFETY NOTICE BOARDS 9



PART TWO


ADM/HSE/Pt 2 00 January 2005 SAFETY SIGNAGE 1 of 9

SECTION 10

SAFETY SIGNAGE

INTRODUCTION

Safety Signs should be used to inform, advise, instruct, warn of danger and improve safety in the

workplace. Signs incorporate certain colours which have specific meanings as follows:

PROHIBITION MANDATORY WARNING SAFE CONDITION FIRE EQUIPMENT

- You Must Not -

- Do Not Do -

- Stop -

-You Must Do -

- Carry out the -

action given by

the sign

- Caution -

- Risk of Danger

- Hazard Ahead -

- The Safe Way -

- Where to go in

an emergency

- To indicate -

Fire Equipment

Outline Circle with

Crossbar

Solid Circle Outline Triangle Square or

Rectangle

Square or

Rectangle

RED

means

BLUE

means

YELLOW

means

GREEN

means

RED

means

STOP OBEY RISK OF

DANGER

GO

FIRE

EQUIPMENT


Ministerial Order No. 32 (year 1982) Article 14


BS 5378: Part 1:1980



PART TWO



10.1 PROHIBITION

• background colour should be white

• circular band and crossbar shall be red

• the symbol shall be black and placed centrally on the background and shall not obliterate

the crossbar

• red shall cover at least 35% of the area of the safety sign

10.1.1 example of prohibition safety signs



PART TWO



10.2 MANDATORY

• background colour shall be blue

• the symbol or text shall be white and placed centrally on the background

• blue shall cover at least 50% of the area of the safety sign

10.2.1 example of mandatory safety signs



PART TWO



10.3 WARNING

• background colour shall be yellow

• triangular band shall be black

• the symbol or text shall be black and placed centrally on the background

• yellow shall cover at least 50% of the area of the safety sign

10.3.1 example of warning safety signs



PART TWO



10.4 SAFE CONDITION

• background colour shall be green

• the symbol or text shall be white

• the shape of the sign shall be oblong or square as necessary to accommodate the

symbol or text

• green shall cover at least 50% of the safety sign

10.4.1 example safe condition safety signs



PART TWO



10.5 FIRE EQUIPMENT

• background colour shall be red

• the shape of the sign shall be oblong or square as necessary to accommodate the text or

symbol

• the symbol or text shall be white

10.5.1 example of fire equipment safety signs



PART TWO




hazard


requirement

symbol signs

Used to identify hazards and mark areas to protect employees

10.6.1 example of hazardous substance control safety signs



PART TWO



10.7 DETERMINING SIGN SIZES

The size of sign required should be assessed depending on the sign viewing distance.

10.7.1 determine the size of signs required as follows

10.8 STANCHION SIGNS

Used for displaying signs on a temporary basis for both indoor and outdoor use, they are

simple to assemble and can be quickly positioned near to a potential danger.

Clips are supplied for retaining signs into the frame, this allows interchangeable messages

to suit the necessary requirements

Single sided Double sided

Viewing distance Viewing distance Viewing distance Viewing distance up to 4.5m (15ft) up to 7.7m (25ft) up to 15.5m (50ft) up to 23m (75ft)

100 150 300 600

450

400

200

100



PART TWO



10.9 SAFETY NOTICE BOARDS

Contractors shall set up and maintain throughout the course of the contract, Safety Notice

boards for the use of his labour force.

Safety Notice boards should:

• be set up in prominent locations on the site that are clearly visible to the Contractors

employees and anyone entering the works

• contain all relevant emergency and contact numbers required for the contract

• be fully illustrated with relevant safety signage showing precautions required

• be safely supported and suitably placed to withstand bad weather conditions e.g. strong

winds

The Contractor’s staff and labour force shall be made fully aware of the safety signs and the

emergency contact information, prior to commencing duties on site.

PERMIT FORM - HOT & COLD WORK

Document No. Rev Date Title Form

ADM/H&S/FM/2.11/1 01 March 2005 HOT & COLD WORK PERMIT 1 of 1

Permit Issued to - Section/Contractor:

To do the Following:

Exact Location:

Validity Period: Date: Duration: (Max.24hrs.) From: To:

A Actions/Conditions

Yes No N/A B Safety Eq. & Protective Clothing

Reqd.

Yes No N/A

Depressurised/ Drained Goggles/Face Visors/Hard Hats

Steamed/Water Flushed PVC Gloves/Safety Boots

Ventilated Properly Respirators

Isolated Mech. & Tagged Escape Sets/Full BA Sets

Isolated Electrically & Tagged Safety Belts/Safety Harnesses & Safety

Lines

Combustible Mats Cleared Three in One Gas Monitor

Lighting is Sufficient Man Riding Winch

Continuous Monitoring Reqd Portable Fire Appliances

Area clean & Safe Overalls - Chemical/Ordinary

C Other Safety/Protective Equipment or Actions Required:

I Certify That I have Inspected the Site, and Subject to all the Safety Requirements detailed in this Permit being fully

implemented, I Confirm that it is Safe for Hot/Cold Work to Start.

Name: Position: Signature: Date:

D Toxic/Hazardous Mats. To

be tested

Safe Limit Test

Result

N/A Time Date Name Signature

Combustibles/Methane Gas L.E.L. 5%

Oxygen Above 19%

Hydrogen Sulphide 10 PPM.

Chlorine 1 PPM.

Carbon Monoxide 50 PPM.

Special Instructions:

E Acceptance by the Person in Charge of the Operation:

I Confirm That I Fully Understand and Will Implement All The Safety Requirements Detailed in This Permit, and

That All Those Under My Control Will Be Fully Informed and Instructed in it’s Implementation.

Name: Position: Company/Section: Signature: Date:

F Completion: Hot/Cold Work is Stopped/Completed At …….............…Hrs. and this Permit may be Cancelled.

Performer/

Person in Charge Signature: ………….....…… Originators Signature: ………..…….…….Date: …………Time …..………

Note: A new Permit Must be Issued For Any Change In Conditions: IMPORTANT: This Permit Does Not Allow

“SMOKING” At Any Time

PERMIT FORM - CONFINED SPACE ENTRY


ADM/H&S/FM/2.11/2 01 March 2005 CONFINED SPACE ENTRY PERMIT 1 of 1

Contractors Name: Contract:

Location of Confined Space:

Work to be done in Confined Space:

This Permit is VALID ONLY from: (hrs) to (hrs) Date P

A

R

T

1

THIS PERMIT COVERS ENTRY ONLY INTO A CONFINED SPACE

All work entailed in effecting entry and after entry shall be covered by the appropriate

WORK PERMIT –See Part 3A below.

P

A

R

T

2

CONDITION OF PLANT

1. The plant/equipment *IS isolated from all sources of danger

2. The main valves ARE closed and locked.

3. The equipment HAS been drained/vented*.

4. Dangerous sludge and other deposits HAVE been removed

5. Mechanical drives HAVE been disconnected.

6. Electrical circuits HAVE bee locked off.

7. The atmosphere HAS been tested and IS free from toxic and flammable

substances.

8. There IS an adequate supply of fresh air to the work location.

Yes/No N/A Signature

P

A

R

T

3

SPECIAL PRECAUTIONS TO BE TAKEN

A. Additional permit for hot work/cold work release* is required.

B. Protective clothing SHALL be worn, (specify type).......................................

C. Safety belt and lifeline shall be worn.

D. Forced ventilation SHALL be provided.

E. Fresh air/self contained *breathing apparatus SHALL be worn.

F. Flameproof/intrinsically safe * lighting SHALL be used.

*delete as applicable

AUTHORISATION:

Signature of issuing authorised person Time: Date

RECEIPT:

I have read this form and understand the special precautions to be taken prior to and during entry.

Signed: (person in charge of the work) Time: Date:

CLEARANCE:

Work in the above enclosed space has been completed (or stopped) and all the men under my charge withdrawn.


P

A

R

T

4

CANCELLATION:

All copies of this permit are hereby cancelled.


PERMIT FORM - ELECTRICAL WORK


ADM/H&S/FM/2.11/3 01 March 2005 ELECTRICAL PERMIT 1 of 1

Project:

Authorisation is given to the Contractor/Person as indicated below , to carry out the following task/s and shall adhere

to the precautions as listed to ensure the work is carried out safely.

Signature: .................................................. (Electrical Engineer) Date: .................... Time: ....................

Location or area of work:

Description of work:

Plant/Equipment/System:

Precautions necessary:

1.

2.

3.

Location of:-

Isolation: …………………………………………….. Locks: ……………………………….……….......

Notices: …………………………………….. …… Earthing (if applicable) ……………..……..…...

Other Precautions: …………………………………………………………………………………………….…...

I acknowledge receipt of this permit and I am satisfied that the precautions taken are adequate and I accept

responsibility for undertaking the work specified above in a safe manner. I declare that neither myself nor those

persons within my control will attempt any task other than as specified above.

Signature: ……………………………………… (Task Supervisor) Date: …………….. Time: ………………

I certify that the work specified above has been completed/stopped*, and that the safety measures have/have not*

been removed.

Signature: ……………………………………… (Task Supervisor) Date: …………….. Time: ………………

I certify that the above safety measures have been removed and the plant/equipment* is safe to operate and is hereby

returned to normal service. This permit is hereby cancelled and his completed form is filed for record purposes.

Signature: ………………………………… (Electrical Engineer)) Date: …………….. Time: ………………

* Delete as appropriate

PERMIT FORM – EXCAVATION WORK/ROAD CLOSURE


ADM/H&S/FM/2.11/4 01 March 2005 EXCAVATION / ROAD CLOSURE PERMIT 1 of 1

Permit Issued To: Section/Contractor: ………………………….………………………………………………….......……….

Details of Excavation Work Required: ……………………………………………………………………………….......……..

Exact Location: …………………………………… Validity Period: From: ………….…......…. To: …………....………

“A” - ELECTRICAL CHECKS

Underground Electrical Cables Yes No - Overhead Electrical Cables Yes No

If present – specify exact location and precautions: …………................…………………………………………………………

MECHANICAL/CIVIL CHECK

Underground Pipelines/Drains etc. Yes No If present – specify exact location and Precautions

………………………………………………………………………………………………………………………....…………..

Name Position Signature Date

“B” - TELECOMMUNICATION CHECKS

Underground Running Telephone Cables etc.: Yes No - If present – specify exact location and Precautions …………………………………………………………………………………………………………………………………........


“C” - SAFETY DEPARTMENT CHECKS

Road Closure: Yes No If yes - Give full details: ………………………………………………………...

Safety Eequipment: (tick box) Road Signs Barriers Flashing Lights Traffic Lights

Other Instructions: …………………………………………………………………………………………………………….

I have personally checked the site and conditions and permission is granted for work to commence under all the above

mentioned precautions.


“D” - ACCEPTANCE BY THE PERSON IN CHARGE OF THE OPERATION

I confirm that I fully understand and will implement all the safety requirements detailed in this permit, and that all

those under my control will be fully informed and instructed in its implementation.


“E” - COMPLETION: Work is stopped/completed. Site Inspected and made safe. Work permit cancelled.

PERSON IN CHARGE

Name Signature

PERMIT ORIGINATOR

Name Signature

DATE TIME

SECTION 11

SECTION 11

PERMIT TO WORK

INTRODUCTION


11.1 FORMULATING THE PERMIT TO WORK SYSTEM

11.2 PERMIT TO WORK GUIDANCE

11.2.1 CONTROL

11.2.2 ASSESMENTS OF RISK

11.2.3 OBJECTIVES

11.2.4 UNDERSTANDING

11.2.5 LINE MANAGEMENT

11.2.6 INDIVIDUAL RESPONSIBILITIES

11.2.7 CIRCUMSTANCES IN WHICH PERMITS MUST BE USED

11.3 ATTACHMENTS

HSE/FM/2.11/1 - HOT & COLD WORK PERMIT

HSE/FM/2.11/2 - CONFINED SPACE ENTRY PERMIT

HSE/FM/2.11/3 - ELECTRICAL PERMIT TO WORK FORM

HSE/FM/2.11/4 - EXCAVATION / ROAD CLOSURE PERMIT



PART TWO


ADM/H&S/Pt 2 01 March 2005 PERMIT TO WORK 1 of 4

PERMIT TO WORK

INTRODUCTION

For work involved in areas defined as confined spaces or when isolation of either Electrical,

Mechanical or High Pressure Systems etc. is required, the most satisfactory way of ensuring a safe

system of work is by observing a permit to work system.

The permit to work is an operational document prepared by a responsible person who is familiar with

the work procedures, the hazards and all necessary precautions and who has carried out a thorough

assessment of the situation.

The permit gives a written authority that the area concerned is safe to enter and the work to start, and

lays down the time when it must stop. It sets out the correct sequence of work, the precise way in

which the work is to be done, the responsibilities of all persons involved, and the safety checks made

and all the precautions taken. The permit to work is not issued until the responsible person has put his

signature to this record, signifying that every step in the sequence of safety checks has been taken.


Ministerial Order No. 32 (year 1982) Article 7 & 9



PART TWO



11.1 FORMULATING THE PERMIT TO WORK SYSTEM

A typical permit to work system should lay down:

• location/description of work to be done

• types and details of hazard/risks involved

• certificate of isolation where appropriate

• safety/protective equipment required

• limitation of time

• authorisation for work to commence

• acceptance by person(s) carrying out the work

• clearance of isolation

• completion of work or renewing certificate

• cancellation of permit

11.2 PERMIT TO WORK GUIDANCE

11.2.1 control

A permit to work procedure is a formal written system used to control certain types of work

which are potentially hazardous.

The term Permit to Work refers to the pro-forma or certificate which forms a part of an overall

safe working system.

The essential features of Permits to Work are:-

• clear definition of who may authorise particular work.

• clear identification of who is responsible for specifying the necessary precautions to be

taken.

• effective instructions and training to all personnel in the issue and use of permits.

• performance monitoring in order to ensure that the safe system is implemented as

intended.

The permit is therefore a written document that gives authorisation to certain people to carry

out specific work within certain time constraints and which sets out the main precautions

needed to complete the work safely and without risk to health and safety of all those who are

involved.

Note: The mere issue of a Permit to Work does not simply give permission to carry out

dangerous work or, In itself, make a job safe.

11.2.2 assessment of risk



PART TWO



The purpose of a Permit to Work system is to ensure that proper consideration is given to

the risk of particular work and that these are assessed and controlled before work starts.

11.2.3 objectives

The primary objectives of the procedure are to ensure proper authorisation of designated

work which may be of certain types and type within certain designated areas (other than

normal production).

11.2.4 understanding

Management and Supervision must ensure that persons involved in such work fully

understand the exact:-

• identity, nature and extend of the job

• the hazards involved

• precautions to be taken

• limitations as to the extend of the work and time during which the work may be carried

out

11.2.5 line management

It is important to ensure that the line manager in direct charge of an area, location, unit,

plant, installation or equipment is fully aware of all the work being done

A system of control must be provided and provisions made for a record showing that the

nature of the work and the necessary precautions have been checked by the appropriate

persons.

Line management should also provide a formal hand - back procedure to ensure that the

part of the plant, installation or equipment affected by the work is in a safe condition before

normal work is resumed.

11.2.6 Individual responsibilities

Clear information, instruction, training and guidance should be given to all who have

responsibilities under Permit to Work procedure including:-

• management, and where appropriate, occupiers and owners

• contractors and sub contractors

• supervisors, foremen and charge hands

• other employees or non management and supervisory staff



PART TWO



11.2.7 circumtances in which permits must be used

These include potentially hazardous non – production work for which Permits to Work are

normally required e.g.

• maintenance

• repairs

• inspection

• testing

• alteration

• construction

• re-construction

• working in confined spaces

• electrical installations

• dismantling

• hot/cold work

• modification

• cleaning

• excavation work

11.3 Attachments

Attachments A, B, C & D are samples of typical formats that can be used when a Permit to

Work is required.

SECTION 12

SECTION 12

PERSONAL PROTECTIVE EQUIPMENT (PPE)

INTRODUCTION 1


12.1 DUTIES 2

12.2 SUITABILITY 2

12.3 HEAD PROTECTION 3

12.4 EYE PROTECTION 5

12.5 HEARING PROTECTION 7

12.6 FOOT PROTECTION 9

12.7 HAND PROTECTION 10

12.8 BODY PROTECTION 11

12.9 RESPIRATORY PROTECTIVE EQUIPMENT (RPE) 12

12.10 SAFETY HARNESSES AND BELTS 16

12.11 ENERGY ABSORBING DEVICES 17



PART TWO


ADM/H&S/Pt 2 01 March 2005 PERSONAL PROTECTIVE EQUIPMENT 1 of 19

SECTION 12

PERSONAL PROTECTIVE EQUIPMENT (PPE)

INTRODUCTION

Where a risk cannot be controlled adequately by other means, employers have a duty to provide suitable PPE.

The use of personal protection in the form of clothing or equipment should be considered as a last

resort in the minimisation of accidents. All too often there is insufficient effort to reduce or eliminate a

hazard, and too much reliance on personal protection to prevent the hazard giving rise to personal

injury.

When engineering control measures are not possible to be provided for total elimination of hazards,

the use of personal protective equipment is required.

There is considerable requirement within the Construction Industry for the use of personal protection,

even as a last resort, in view of the fact that, even on the safest of sites, hazards are not totally

eliminated.

In this section, required safety standards and advice is given on the following items:

Head Protection

Eye Protection

Hearing Protection

Foot Protection

Hand Protection

Body Protection

Respiratory Protective Equipment (RPE)

Safety Harness and Belts

Energy Absorbing Devices


British Standards referred to in applicable sections

Ministerial Order No. (32) Year 1982 – Article (1), (6), (9), (15), (22)

Part V–Industrial Safety Preventative Measures, Health & Social Care for Workers – Article (91)



PART TWO



12.1 DUTIES

12.1.1 employers

• assess hazards and risks prior to work to ensure proper selection and adequate provision

of personal protective equipment.

• ensure arrangements for employees to report loss or defects to enable replacement or

repair, before the employee concerned is allowed to re-start work.

• equip all visitors with a minimum of hard hats and safety boots.

• erect signage to inform of PPE requirements when entering a site area and near site

hazards (see signage section)

• provide suitable storage arrangements for when PPE is not in use.

• ensure the user is trained in :

- the hazards of the activity that PPE is required for,

- how the PPE is used,

- limitations of the PPE,

- maintenance, storage and inspection requirements.

12.1.2 employees

• be trained before using any PPE

• make full and proper use of PPE.

• care for PPE and follow any maintenance requirements.

• report any defects or loss, and where appropriate, return PPE to storage after use.

12.2 SUITABILITY

12.2.1 recognised marking

• All PPE shall either have a BS kite mark or CE mark (both being recognised marks for PPE tested and approved to International Standards).

12.2.2 inspection and maintenance

• properly trained persons should examine PPE in accordance with manufacturer’s

recommendations prior to issuing.

• the wearer should also inspect it before use to ensure that it is clean and not defective.



PART TWO



12.2.3 checks

To be suitable, PPE must:

• be assessed as appropriate both to the risk and the work condition.

• be selected to take account of factors such as length of time it needs to be worn and the

need to see and hear.

• be capable of fitting the wearer correctly.

• be compatible with other PPE which may need to be worn (e.g. safety helmets and

hearing protection).

• carry a CE mark, BS Kite mark or other mark to internationally recognised standard.

• be comfortable and convenient to the wearer.

• allow wearer to be selective and have a degree of choice, where appropriate, before final

selection is made.

12.3 HEAD PROTECTION

In the vast majority of construction operations, there is a foreseeable risk of persons

incurring an injury to the head, either due to falling material, or due to the head striking

against another object.

12.3.1 required safety standards

• a safety helmet is required to be

used on construction sites,

excavation work, overhead crane

operation, low structures / pipes /

beams or wherever there is risk of

head injury.

• All contracts shall be classed as

“Hard Hat Areas” and notices shall

be displayed.

• anyone having control over other

persons at work has a duty to ensure

that head protection is worn. This

applies to main contractors, sub

contractors and also to individuals

such as site managers, foremen,

engineers and surveyors.

Examples below are situations where

head protection may not be required,

but will still have to be worn to cross the

site:

∗ maintenance or decorative work

on completed buildings where

there is sufficient headroom

and no multi layers of working

levels

∗ inside site offices, temporary

accommodation etc.

∗ inside the cabs of vehicles and

plant, if provided with falling

object protection

∗ when work is at ground level,

e.g. roadworks such as kerb

laying or resurfacing



PART TWO



12.3.2 main types of head protection

12.3.3 use and maintenance of head protection

• for the harness to be properly

adjusted, but not too tight, and for

the helmet not to be worn at an

angle.

• to keep the clearance between

helmet and harness; i.e. nothing

must be carried in the helmet.

• to handle the helmet with care.

• for regular inspection of the helmet

shell for cracks and signs of wear

and of the harness for loose or

broken straps, worn stitching etc.

• not to paint, mark or label a helmet,

as this can affect its protective

properties.

• to minimise exposure to sunlight,

extreme heat or cold, chemicals etc.

• to remove all dirt and moisture after

use with warm soapy water.

• to provide places to store correctly,

when not in use.

• to request a replacement, if the

helmet is lost or the harness is

damaged.

industrial safety helmets/hard hats

should conform to BS EN 397 Industrial hard hats - heavy

duty, or an equivalent standard. Photo shows safety helmet

shell and section through to the harness.

industrial scalp protectors/bump caps

should conform to BS EN 812 Industrial hard hats – light

duty, used as protection against abrasion or bruising in

confined spaces, such as ducts etc. They are intended only

to protect against minor risks and must not be used where

industrial safety helmets are required.



PART TWO



12.3.4 accessories

When determining the type of helmet to be supplied, consideration should be given to other protective equipment which may be needed to be worn. Equipment, which can be mounted on safety helmets, includes:

12.4 EYE PROTECTION


• should be to BS EN 166 which covers general industrial eye protectors including

spectacles, goggles and face shields.

• suitable face and eye protection must be worn by employees to protect face/eyes against

any flying particles / splash of chemical / hot solutions.

• impact resistant safety glasses with side shields / safety goggles/full face shield suitable

for grinding, buffing, chipping operations shall be provided and used.

• welding masks with appropriate filter glasses must be used when performing welding

operations and be to BS 1542.

• in addition, eye wash fountain shall be readily available at the site. In remote locations,

eye wash bottles may be substituted.

chin straps

used for work that might cause the helmet to fall off e.g. steel

fixing, where much of the work is done whilst bending over.

ear defenders

built in brackets for the attachment of hearing protectors when

working in a noisy environment.

lamp brackets

these allow lights to be fitted to safety helmets for work in dark

areas.

face shields

may be fitted to certain helmets by a swivel mount fitting. These may

be needed on operations where there is a danger of flying particles,

chemicals etc.



PART TWO



12.4.2 types of eye protectors

safety spectacles

these include those with robust Acetate frames with

toughened glass lenses and Lightweight Nylon frames.

Side shields are fitted for lateral protection. Safety

spectacles are available in both Grade 1 and Grade 2

standards.

safety goggles (box goggles)

wide vision goggles, usually with lenses giving General

Purpose Grade 2 or Grade 1 impact protection. The

ventilation styles offered cover most industrial hazards,

e.g. dust, chemical and gas hazards. “Antimist” and

“Molten Metal Splash” approved goggles are also

available. This type of eye protection can be worn over

ordinary prescription goggles.

welding goggles and shields

fibreglass polyester welding shields are available either as

hand shields, or, as with face shields, fitted to the safety

helmet lens holder. Welding filters are supplied depending on

the wearer and job requirements.

welding spectacles welding goggles welding shield

face shields

lightweight face shields in acetate, polycarbonate, etc. are

manufactured for total eye and face protection and can be

worn secured to the front of the safety helmet. Styles vary

(brow guards, flare etc.) as does length of visor. Models are

available for antiglare and gas welding. Light mesh type face

shields are available for use with chain saws etc. when cutting

timber.



PART TWO



12.4.3 eye protectors are marked as follows

Type/Hazard Marking

General purpose industrial eye

protection

BS EN 166 S

Impact Grade 2

Impact Grade 1

BS EN 166 F

BS EN 166 B

Molten Metal goggles BS EN 166 - 9

Chemical goggles BS EN 166 - 3

Dust goggles BS EN 166 - 4

Gastight goggles BS EN 166 - 5

Lens filters (for welding) BS 679

Face and hand shields : helmets for

protecting during welding

BS 1542

Note: Glass lens supplied for use in impact and/or molten metal eye protectors in

combination with plastic lenses, must be additionally marked with the word “outer”.

12.5 HEARING PROTECTION

Ear defenders are used to prevent loss of hearing when persons would otherwise be

exposed to levels of noise which are considered to be hazardous.

The maximum levels to which persons may be exposed are expressed as a function of

intensity and time, e.g. 90 decibels [db (A)] for a period of 8 hours, or its equivalent This

value is quoted as the ‘equivalent continuos sound level’ or 90dB(A) Leq (8hr). The noise

levels in any particular working environment should be determined by measurement with

meters but, as a rough guide, if it is necessary to shout over a distance of 1 metre or less in

order to he heard, then the noise level may be excessive.


• persons working in areas with excessive noise above 90 dB(A), shall wear ear muffs/ear

plugs.

• hearing protection should conform to BS EN 352 Hearing Protectors: Safety

Requirements and Testing.

• high noise level areas should be identified and appropriate warning notices should be

exhibited to warn employees.



PART TWO



12.5.2 types of hearing protection

In order to combat noise, which cannot reasonably practicably be, reduced sufficiently at

source, ear protection, which may range from the simplest forms of ear plugs to extremely

efficient ear muffs and noise helmets, must be used.

ear plugs

These are effective in relatively low noise level areas and many different types are now available e.g:

• disposable types of wax impregnated cotton wool, glass

down or similar materials with are shaped and inserted in

the ear canal.

• permanent moulded pre shaped plugs of fiber or plastic for

insertion into the ear canal.

• foam ear plugs which are compressed in order to fit into the

ear and expand to maximise protection.

Notes: - plain cotton plugs do not give adequate protection.

- some ear plugs are supplied in different sizes and it is important that the

correct size is used..

ear muffs

• these consist of two rigid cups or shells which cover

the ears and are fitted with absorbent material. They

fit to the head by means of soft sealing rings known

as ear seals. The ear cups are connected to suitable

headbands so designed to maintain cups firmly

against the ear. Seals are either fluid or foam filled.

Note: - Fluid seals may not be sufficiently robust to

withstand the rigours of the construction

environment.

12.5.3 communication systems

These are available incorporating receivers in the ear cups and are operated, generally on a

loop transmitting system, to enable the wearer to receive messages.

An alternative is a two way wired communication system, incorporating noise cancelling

boom microphones and amplifiers in the ear cups that can be connected together allowing

two way communications in noisy areas. This could have particular application where noisy

work has to he carried out in confined spaces, such as sewers, where effective

communication is essential.



PART TWO



12.5.4 selection of hearing protection

level of protection

The level of protection (amount of noise reduction) offered by hearing protectors, known as

the attenuation, will be dependent on the frequency of the sound source. Each manufacturer

of ear protection will have available an attenuation chart or graph showing the level of

attenuation at a range of different frequencies. Also quoted will be a standard deviation and

this figure should he deducted from the attenuation value to determine the assumed

protection. This is only if the equipment is properly fitted and adequately maintained.

compatibility with other PPE

Hearing protection, particularly ear muffs, should be selected so that it is compatible with

other items of protective clothing which may have to be worn.

12.6 FOOT PROTECTION


• safety footwear should conform to: BS EN 345, BS EN 346 & BS EN 347 or equivalent.

• standard safety boots with metal toe caps must be worn by all personnel on site and in

places where foot injury could occur.

• in specific operations, rubber boots with steel toe should be used.

12.6.2 protective footwear is used to

• provide protection to the toes in the event of material falling on the foot by the use of a

steel toecap built into the boot or on the outside surface.

• prevent injury by the penetration of nails and similar sharp objects. Steel midsoles are

standard only on some boots and shoes and is preferred for building construction sites.

• provide protection against the ingress of water.

Rubber/wellington boots are used when persons are required to

work with their feet in wet substances, such as concrete or mud

and for work in places such as sewers.

• provide a good grip on surfaces which are potentially

slippery.

• provide protection during certain specific operations, e.g

special electrical safety shoes should be used by those

involved in electrical trades.



PART TWO



12.6.3 selection

The selection of foot protection will depend primarily on the assessed risk. In general, safety

boots rather than shoes are recommended for site work as they provide support for the

ankle on uneven or soft ground. Where there is a risk of injury from penetration or crushing,

protective steel toecaps and midsoles will be required.

comfort

• comfort is an important factor to be considered particularly in the selection of

rubber/wellington boots which are obviously required to be 100% waterproof. Rubber and

PVC boots are inexpensive, but they are not permeable; moisture is kept out, but

perspiration is kept in. With such boots the wearing of socks is recommended, but it is

important that these are regularly washed.

• the weight factor particularly with boots having safety features such as steel toe caps and

midsoles can he important with respect to foot comfort.

• steel toe caps, designed to protect toes from falling objects may bruise and chafe the

toes across the foot joint after prolonged wear. It is important to choose the correct size

of footwear allowing for the type of socks to be worn.

12.7 HAND PROTECTION


• hand gloves must be used in jobs likely to

cause injury to hands.

• gloves must be used near moving machinery

parts.

• PVC/rubber gloves must be used when

handling chemicals.

• electricians using tested rubber gloves must

check them for defects prior to start of work.

• select and use the gloves suitable for the job.

12.7.2 selection

The first consideration in the selection of industrial protective gloves must be to identify the

hazard to be overcome and the handling requirements.

The handling of small components will require that the glove must be highly flexible and give

good dexterity to the worker.



PART TWO



12.7.3 considerations when selecting

abrasion

gloves which are used to protect against abrasion will usually be of

leather, or those having leather palms. Where gloves are to be worn in

the wet, polyvinyl chloride (PVC) will give a high standard of water, oil

and chemical resistant, in addition to preventing abrasion.

grip

where grip is important, gloves made of a base material such as knitted

nylon or cloth with a latex coating, are suitable

chemical resistance

air-impermeable (plastic or rubber) gloves will be necessary for

operations such as degreasing, paint spraying and pesticide handling.

heat resistance

this will be required by welders, burners and other such as those working

on live heating systems. Leather gauntlets will be appropriate for these

trades

water resistance

resistance to water and other fluids is rarely a quality which is

required on its own and PVC gloves resistant to abrasion would

normally be suitable.

12.8 BODY PROTECTION


• wear proper protective clothing/coverall.( Loose or baggy clothing is not permitted in work

areas).

• a PVC apron must be worn against splash from any chemical or corrosive substances,

• a leather apron is required to be worn by welders and others where there is potential

hazard of hot metal/sparks.

• full PVC suit to cover full body is required for persons entering tanks/vessels/sumps/pits

to protect against any chemical/corrosive substance.



PART TWO



12.8.2 types of body protection

wet weather clothing

usually In the form of PVC either one or two piece suits, and often in company livery. PVC

clothing is particularly prone to condensation on the inside and the incorporation of vents will

help alleviate the problem. Clothing manufactured from a breathable fabric (Gortex) is

available, but is quite expensive.

high visibility clothing

normally in the form of waistcoats or jackets for use when workers

are working adjacent to moving traffic, either on public highways,

or on such operations as earth moving. These garments will

incorporate retro reflective strips front and rear.

overalls

these will normally be made of poly cotton and arrangements must

he made for regular cleaning- Specialist trades such as asbestos

strippers and lead burners will have lightweight overalls suited to

the operation; such overalls may be of the disposable type.

leather aprons

used by welders and burners to provide protection against sparks and molten metal which

might otherwise ignite their clothing

trousers

incorporating ballistic nylon or similar material, are available to give round leg protection to

chain saw operators.

12.9 RESPIRATORY PROTECTIVE EQUIPMENT (RPE)

Whether toxic materials, which are liable to produce, dust, gases or vapours are being used,

or are present in the working environment, there is always a respiratory hazard. Ideally, the

contaminant should be controlled at source to minimise the hazard, but this is often not

possible. If it is necessary to provide RPE the first step is to determine whether the

environment is deficient in oxygen, in which case, air supplied equipment (breathing

apparatus) must be used; if sufficient oxygen is present, but the air is contaminated air,

purifying equipment (respirators) can be used.

The overall choice of equipment is wide. As the wrong choice could seriously affect the

health of the wearer, or lead to asphyxiation, expert advice is essential combined with

training and information being given to the wearer. In addition, cleaning and maintenance

facilities for the equipment must be provided to ensure continued effective protection.



PART TWO




• dust mask respirators must be worn to protect against dust particles.

• chemical cartridge respiration must be worn when painting/spraying solvent or chemicals.

• when there is potential for the presence of toxic gas/vapor or oxygen deficient

atmosphere, the self-contained breathing apparatus (SCBA) should be used.

• only authorized /qualified personnel can issue Respiratory Protective Equipment.

• persons trained /certified on the usage of self contained breathing apparatus shall be

engaged and the work should be done under direct supervision. The basic tests to

ensure proper fitting of face masks must be done before each operation.

• proper selection and use of RPE should be ensured by taking into consideration

hazardous operation, contaminant, time, protection from the particular equipment,

limitations, state of health of individual.

• when working with asbestos, staff shall be provided with respiratory equipment approved

for use with asbestos which does not allow penetration by, or retain dust and which

should be a close fit with head cover.

• when engaged in grit blasting, the use of air supplied hood is essential If blasting in direct

contact with the dust / grit.

12.9.2 types

Inhaled air is drawn through a medium that is designed to remove most of the contaminant.

It is imperative that the correct medium is used for the particular contaminant and, where

dust and fibres are concerned the actual size range of the particles is an important

consideration. Filters are used to collect dust and fibres whereas, for gases and vapours, a

chemical absorbent is used usually contained within a replaceable cartridge.

disposable respirators

manufactured from filtering material and are usually termed

filtering facepeices or facemask. The facepiece is at a

negative pressure.

half mask respirator

made from rubber or flexible plastic and designed to cover nose

and mouth. They are fitted with a single or two side-by-side

replaceable cartridges, different ones being available to protect

against a range of dust. gases and vapours. The facepeice is at

a negative pressure.



PART TWO



full-facepeice respirator

are made from rubber or flexible plastic, but designed to cover the nose, mouth and eyes.

The filter median is contained in a cartridge or canister directly coupled to the facepiece or

connected via a flexible tube with the appropriate filter fitted, it is suitable for either dust

gas or vapour and the facepiece is at a negative pressure.

positive pressure powered respirators

have filtered air supplied to the breathing zone, via a flexible tube from a battery powered

blower. The filter fan and battery are usually fixed around the wearers waist. Alternatively

positive pressure to the breathing zone may be provided by a blower and filter mounted in

the respirator, with only the battery fixed to the wearers waist, as shown opposite.

12.9.3 breathing apparatus

Used primarily where the atmosphere is deficient in oxygen as may occur in confined

spaces. However it is sometimes used in other circumstances where the atmosphere is

contaminated, e.g. in the removal of asbestos insulation and coating. The equipment

consists of a facepiece by which the wearer can breathe uncontaminated air, either drawn

from fresh air or supplied by compressed air.

fresh air breathing apparatus

consists of a full facepiece, with insulation and exhalation valves connected by a non

kinking hose to fresh air. The hose is normally less than 25mm in diameter and should not

exceed 9m in length unless breathing air is assisted by means of a hand or mechanical

power to maintain a positive pressure in the facepiece.

compressed air-line

breathing apparatus, in which an is supplied to the

facepiece through an air line from a compressor. These

devices depend on a good face fit. They may supply air

on demand (by suction demand or positive pressure

demand), or they may provide air continuously to the

facepeice.

self contained breathing apparatus

in which the air supply is provided to a full face piece

from cylinders carried on the back. Air may be supplied

to the wearer on demand, or the exhalation and

demand valve may be so designed that a positive

pressure is maintained inside the facepiece.



PART TWO



12.9.4 selection

RPE should be selected so that the wearer does not breathe level of contaminants above

the relevant occupational exposure limits. A wide range of equipment is available, which

have various limitations in respect of efficiency and wearability. Proper selection is essential

if wearers are to receive adequate protection.

Heat stress call also be a factor when working in hot and humid atmospheres, or when

clothing is sealed as in asbestos stripping. The cooling effect of the supplied air in power-

assisted equipment and the low breathing resistance, make it more acceptable than non-

powered equipment.

Freedom of movement must also be considered. With compressed air line, breathing

apparatus movement is restricted by the air line, which must not become entangled or

kinked. Self-contained breathing apparatus does not have this limitation, but is bulky and

heavy; power assisted respirators are lighter.

12.9.5 use of RPE

Where a face piece is incorporated, a good seal is essential. Where it is possible to close

the inlet of the equipment, e.g. by a card over the filter, the wearer should carry out the

following “negative pressure test” each time the respirator is worn:-

• after the harness straps have been properly tensioned and adjusted, the inlet should be

lightly closed and the wearer should inhale gently. The face piece should collapse

slightly. Excessive leakage is indicated if the face piece does not collapse, in which case

the equipment should be readjusted and the test repeated. If excessive leakage is still

indicated, it is unlikely that the equipment will be suitable to the wearer. Alternative

equipment should then be made available for test.

In the case of power assisted respirators fitted with face masks, loss of air flow will be

indicated by increased breathing resistance.

12.9.6 inspection and storage

All equipment, with the exception of disposable types, require cleaning, disinfecting and

inspection after use and before wearing by another person, and properly stored when not in

use.

12.9.7 training

Training in the use and application of RPE is essential for all types of equipment. Only

persons who are thoroughly familiar with the equipment and know the procedure to adopt in

an emergency should wear RPE.



PART TWO



12.10 SAFETY HARNESSES AND BELTS

The main reason for the use of safety harnesses is to limit the distance of any fall and

thereby minimising the risk of injury. They will also be used to facilitate the rescue or persons

working in confined spaces, such as manholes etc. Safety belts are not suitable for arresting

a fall, but only as a restraint to prevent access to a danger area.


• safety belts with life lines must be worn when hazards of falling from height exist or when

working on elevated platforms or baskets. Select the proper safety belt and use it.

• safety belts shall be examined periodically. Defective and worn out safety belts must

never be used.

• rescue safety belts with harness / life line must be worn when an employee is working in

a confined space.

• when using ladders, a fall arrest device connected to body harness must be used.

12.10.2 types of harnesses and belts

full body harness

this comprises straps, fittings, buckles etc. suitably

arranged to support the whole body of a person and to

restrain the wearer during a fall and after the arrest of a

fall. The harness should be fitted with a lanyard which will

limit the fall to maximum of 2m. The use of an energy

absorber to further minimise risk of injury during arrest, is

strongly recommended.

general purpose belts and chest harnesses

are used in situations where short duration work is necessary in areas where provision or

fall prevention measures would be impracticable. Belts and harnesses should be fitted with

a line of the appropriate length to prevent access to the danger area.

rescue harness

a rescue harness is used for protecting or rescuing workmen entering dangerous enclosed

places It must be capable of reasonable adjustment, be easy to fit in an emergency, and

be used in such a way that the fall is limited to 600mm.



PART TWO



12.10.3 use of harnesses and belts

It is of the utmost importance that, whenever a safety belt or harness is provided, there is

also an effective means of fixing it to the structure at all times while the protection is

required. All too often, a belt or harness is provided in the hope that the wearer may find

somewhere to attach it. It is also vital that that the fixing point for a harness is strong enough

to withstand the snatch load of a fall. The use of two lanyards will sometimes be necessary

to ensure constant attachment whilst moving.

The distance of fall should be as small as is possible, and to that end, the harness lanyard

should be fixed to the structure, or fixing point, as high as practicable above the working

position.

12.11 ENERGY ABSORBING DEVICES

An energy absorber should be part of a fall arrest system whenever possible. In order to

reduce the possibility of injury to the body in the event of a fall, energy absorbers have been

developed. These devises installed between harness and the anchorage point, allow the fall

to be slowed down, thus absorbing energy and reducing the final load on the body.

12.11.1 types of energy absorbing devices available

A pack containing a strip of 350 lbs nylon tear web,

parallel with a main load-bearing web, together linking

the nylon lanyard to the safety harness. In the event of a

fall, the tear web absorbs the shock as it tears apart.

A corrugated curved stay of metal designed to reduce

the shock by straightening out under a shock load.

A simple rubber labrinth through which the anchorage

rope is threaded.



PART TWO



12.11.2 selection

The selection of energy absorbing devices is as important as the proper selection of your

body belt or full-body harness.

• one of the most important aspects of selecting energy absorbing devices is fully

planning the operation before it is put into use. Probably the most overlooked

component is planning for suitable anchorage points.

• lanyards should be kept as short as possible to reduce the possibility of serious injury

and should not exceed 2 metres.

• ensure that forces incurred during a fall would be less than 1,800 lbs.

• ensure the anchorage point and device will take the dynamic loads generated in a fall.

• energy - absorbing device selected should match the particular work situation, and any

possible free fall distance should be kept to a minimum.

• consideration should be given to the particular work environment and conditions. For

example, the presence of acids, dirt, moisture, oil, grease, etc., and their

effect on the device, should be evaluated. Hot or cold environments may

also have an adverse effect on the system. Wire rope should not be used

where an electrical hazard is anticipated.

12.11.3 use

• choose the correct type of anchorage point or restraint system.

• choose the correct type of equipment.

• assess the possible free fall distance.

• check for dangerous obstacles which a person could hit or swing into.

12.11.4 inspection

• check the equipment prior to use for damage (If in doubt seek expert advice

or replace it)

Note: If a harness and lanyard has been subjected to a fall, they should be disposed of and

replaced. The human eye cannot evaluate the stresses that have been put on the

equipment and next time they may not work. A suitably qualified person should

inspect energy absorbing devices, anchorages and systems annually or following a

fall.

12.11.5.1 training

• ensure you have received comprehensive instructions from the supplier as to

the devices proper use and application.



PART TWO



• train personnel in the correct use of equipment and the procedures that

should be followed.

• put in place emergency procedures and have means available to promptly rescue an

employee should a fall occur, since the suspended employee may not

be able to reach a work level independently.

SECTION 13

SECTION 13

SITE TRANSPORT

INTRODUCTION 1


13.1 TRAINING 2

13.2 VEHICLE SAFETY CHECKS 2

13.3 SELECTION OF DRIVERS/OPERATORS 2

13.4 GENERAL SAFETY RULES 3


H&S Codes of Practice Manual

PART TWO


ADM/H&S/Pt 2 01 March 2005 SITE TRANSPORT 1 of 3

SECTION 13

SITE TRANSPORT

INTRODUCTION

Transport accidents continue to contribute to the overall toll of injury and consequent personal misery.

About one quarter of all fatal industrial accidents involving transport occur in construction. Common

sense therefore suggests the need for clear rules and systems of work to ensure the safe use of

vehicles in the construction environment.


In compliance with Abu Dhabi Police Traffic Regulations



PART TWO



13.1 TRAINING

The provision of adequate training and instruction is a legal requirement as well as being

essential to good general safety management. This is particularly so in regard to the safe

use of mechanically propelled vehicles.

13.2 VEHICLE SAFETY CHECKS

• at the commencement of each day/shift the driver should check the following items as

appropriate :

∗ fuel

∗ water

∗ oil

∗ tyre pressure and soundness

∗ wheel nuts (in place and properly tightened)

∗ efficiency of brakes and steering mechanism

∗ efficiency of lights, horn, reversing light/klaxon, direction indicators, flashing beacon,

windscreen wipers/ washers, etc.

∗ batteries – for secure placing, cleanness, corrosion, and correct electrolyte level

before use and charging.

• any defects, damage or other condition considered by the driver as being likely to make

the operation of the vehicle unsafe should be reported immediately.

13.3 SELECTION OF DRIVERS/OPERATORS

Persons selected to drive site vehicles should be physically fit with normal eyesight and

hearing. They should be mature, reliable and have the capacity to carry out the work in a

responsible manner.



PART TWO



13.4 GENERAL SAFETY RULES

• the authorised driver is at all times responsible for the safe operation of his vehicle. He

must ensure that all movements are made smoothly and at a safe speed. Site speed

limits must not be exceeded. Unauthorised persons must not be permitted to operate the

vehicle.

• the driver must ensure that the vehicle is not overloaded and that the load is secure.

• the vehicle should be kept tidy and free from tools, rubbish or other materials which could

obstruct the controls.

• passengers must only be carried on vehicles, trucks, etc. designed for the purpose and

fitting with fixed seating. Vehicles which do not meet this standard should display a notice

stating “NO PASSENGERS”.

• vehicles must not be manoeuvred too close to excavations so that they run the risk of

causing the sides to collapse. There is also the danger that a laden vehicle may fail to

stop at the edge.

• the driver should not leave his vehicle unattended with the engine running. When parked

on an incline, in addition to applying the parking brake, the engine should be left in gear

and wheel chocks used to prevent movement.

• before reversing the vehicle, the driver must ensure that there is no obstruction in his

path and should obtain the assistance of a banksman or signalman to accompany him

and direct the operation. Where appropriate, audible/visual warning devices should be

fitted to indicate that a vehicle is reversing.

• no vehicle may be used on the public highway unless:

∗ the driver is in possession of a valid current driving licence issued under the

authority of the Road Traffic Acts:

∗ the vehicle is licensed for use on the public highway and complies with Department

of Transport inspection and test requirements.

• when an emergency or rescue towing operation is necessary, the connection between

the towing vehicle and the casualty should, wherever possible, be by means of a solid

bar and purpose-made towing apparatus. Lifting gear should not be used unless this is

unavoidable, in which case it should not be used again in a lifting operation until it has

been re-tested/examined, as appropriate, by a competent person.

• no person must remain on any vehicle, truck or wagon whilst it is being loaded by

mechanical means if he is endangered by doing so. Where a falling objects protective

structure is fitted to a vehicle, it is normally acceptable for a driver to remain in his cab.

SECTION 14

SECTION 14

MOBILE PLANT & EQUIPMENT

INTRODUCTION 1


14.1 GENERAL PLANT AND EQUIPMENT 2

14.1.1 drivers, operators and banksmen 2

14.1.2 maintenance 2

14.1.3 general precautions 3

14.1.4 tyre changing 3

14.2 SPECIFIC TYPES OF PLANT AND EQUIPMENT 4

14.2.1 earthmoving plant 4

14.2.2 fork lifts and telescopic materials handlers

14.3 PRECAUTIONS WITH SOME MISCELLANEOUS MOBILE PLANT 14



PART TWO


ADM/H&S/Pt 2 01 March 2005 MOBILE PLANT & EQUIPMENT 1 of 14

SECTION 14

MOBILE PLANT & EQUIPMENT

INTRODUCTION

Mechanical plant and equipment in use in the Construction Industry are available in a wide and ever

increasing variety. The categorisation of such plant and equipment can be produced as follows:

∗ earthmoving Plant

∗ miscellaneous Mobile Plant

This section covers hazards common to the above categories in addition to those hazards specifically

associated with the safe control of individual items of mobile plant and equipment.


Ministerial Order No 32 (year 1982 Articles 11 - 14

In compliance with Abu Dhabi Police Traffic Section Regulations



PART TWO



14.1 GENERAL PLANT AND EQUIPMENT

14.1.1 drivers, operators and banksmen

The minimum required, but not limited to, qualifications of all drivers, operators and

banksmen of mechanical plant and equipment, are as follows:

• competence in performance of their duties.

• attainment of the legal age (as per Applicable UAE Legislation Section above) and to be

eligible of driving and operating such equipment.

• achievement of training on the correct operation of the specific plant or equipment, the

limitations of its use, and the hazards which exist if, it is not used properly.

• full awareness of usage instructions for the plant and equipment that will be operated by

them.

• ability to maintain stability of the mobile type plant they use and its load at all times.

• awareness that mobile plants should be parked on firm, level ground, with the engine

turned-off, brakes on, and any load lowered to the ground.

employers responsibilities

• ensuring that their drivers, operators and banksmen have the minimum of the

qualifications and achievements mentioned above.

• establishing a procedure to ensure that only drivers and operators, holding Certificates of

Authorization issued by the appropriate authority, use their equipment.

14.1.2 maintenance

It is only after proper maintenance that mechanical plant or equipment will remain safe to

operate. In this regard, the measures to be undertaken by the person, or department

assigned by the user to do the maintenance of the plants or equipment, are as follows:

• establishing a programme whereby every plant and mechanical equipment is regularly

and systematically inspected, serviced, maintained and repaired as necessary.

• maintaining during repair and maintenance activities a safe system of work whereby

permit to work system, like lock-off systems, are established to ensure that no part of the

equipment can accidentally go into motion while work on it is in process.

• ensuring that measures like the propping of raised attachments (e.g. bodies, cabs, etc.)

are applied to prevent the occurrence of accidents as a result of accidental lowering.



PART TWO



14.1.3 general precautions

General precaution measures, as listed below, are to be seriously implemented by all

involved persons. These measures can be summarized as follows:

• minimum clearance distances are to be preserved whenever operating plant and

equipment are used in the vicinity of overhead, buried electrical cables and underground

gas mains.

• clear visibility of mobile plant drivers should be secured at all times. The following

measures must be secured:

∗ restricting speed limits, applying one-way traffic system within the site, in addition to

the spraying of water can help prevent dust from impairing visibility.

∗ keeping all persons not performing any activity related to the work under execution,

well outside the work boundary of working plant and equipment.

• driver of mobile plant should be provided with well-trained banksmen as necessary.

• drivers should never remain on a vehicle being loaded unless falling objects protective

structures/ cabins are used.

• drivers should always use the safe means of access to the cab (like ladders, steps, stairs

etc.) that should always be provided.

• noise produced by powerful plants should be reduced at source to a minimum. Persons

performing work around noisy plant must wear hearing protection, and, where applicable,

protective clothing. (refer to section 1)

• all mobile plant should be properly equipped with lights, side and rear view mirrors.

14.1.4 tyre changing

Failure to follow proper tyre changing procedures can lead to serious accidents, injuries or

death. The general guidelines for tyre changing are the following:

• only trained persons having the proper tools are to mount or dismount, inflate or deflate

tyres which should be carried out following the manufacturers’ recommended

procedures, especially if the tyre is ballasted.

• maximum inflation pressures specified by the manufacturer should be posted on the

equipment using a clear label as close as possible to the tyres location.

• persons should be trained to distinguish between the different required precautions with

the different designs and sizes of tyres.

• the jack should never be relied upon on its own to support a machine during the changing

of a tyre; sound and substantial timber must be used as a support for the jack.



PART TWO



• before removal, tyres must be

deflated and the pressure in the

stem should be decreased by

depressing the valve core stem.

• during the inflating of a tyre, either

a safety cage or extension to the

air hose should be used to prevent

any accident or occurrence to

persons standing over or in front of

the tyre. (see Fig.1)

14.2 SPECIFIC TYPES OF PLANT AND EQUIPMENT

14.2.1 earthmoving plant

general

• when earthmoving plant are driven on the highway, tooth guards should always be fitted

to excavator bucket teeth.

• when loading/unloading earthmoving plant on to a transporter vehicle, measures to be

taken are: (see Fig.2)

∗ the plant operator should supervise the loading/unloading of the plant under the

directions of the transporter driver to ensure that such activities are done at low

speed and safely.

∗ the vehicle should be designed to carry loads exceeding the anticipated maximum

floor load to be carried.

∗ the carried plant should be securely fixed so that there is no possibility of potential

moving, toppling, or falling off the vehicle during transport. Brakes are to be also

engaged.

∗ best arrangements of the plant on the transporter vehicle should be made so as to

eliminate the possibility of the load blocking the driver’s visibility, especially to the

rear.

∗ the carried plant should also be loaded in such a way as to keep its center of gravity

as low as possible, and as close as possible to the centerline of the vehicle in order

to increase its stability.

∗ the availability of sufficient area to prevent the striking of the machine with

obstructions, is to be checked.

Fig. 1 - Example of a tyre cage mounted on a fixed column which will effectively protect the operator should the tyre explode.



PART TWO



∗ the transporter on which the plant is loaded should be parked on a firm and level

ground and never on a ramp with an unsafe angle.

Type

crawler tractors

(dozers)

Brief about machine

All-purpose powerful

machines for pushing and

pulling. Usually noisy and

with restricted vision.

Measures and Precautions to be Undertaken

• Require supervision of the machine and nearby site activities.

• Special care to be made in soft fill areas since there is possibility of sinking of the lower track deeper than

the upper one.

Lashings from rear towing point prevent forward movement and movement of dipper arm

Lashings from front towing point through idler sprockets prevent rearward movement. Note tracks butted against stowed loading ramps

Fig.2 – Diagram showing how to safely load an excavator onto a transporter.



PART TWO



Type

scrapers

Brief about machine

Motorised scrapers are

fast movers of soils.


• Require well maintained haul roads for safety

• Minimum clearance to be kept between closely operating scrapers is 25m

• To be in low gear during downhill travel

• During travel, the bowl should be kept high enough to prevent any collision with low objects and ground, and

low enough to prevent any instability occurrence on turns.

Type

360º Excavators

Brief about machine

Obviously, used for

excavating and are

available in two types:

Mounted on tracks and

Mounted on wheels


• A minimum clearance of 60 cm is to be kept in order to allow for tail swing.

• No person should be present in the work area of the excavator. When necessary, the person may access

this zone only after informing the operator by signs or radio.

• Size of the bucket as recommended by the manufacturer should never be exceeded.

• The machine should be positioned so that the wheels or tracks are at 90ºto the workface to allow for rapid

withdrawal when necessary.

• The bucket should not be extended too far in the downhill direction so as to prevent unstable conditions.

• It is advisable to use stabilizing devices when wheels-mounted excavators are in operation.



PART TWO



Type

180º backhoe

loaders

Brief about machine

Serving in excavating

and/or loading excavated

materials.


In addition to those applicable to excavator (item c above), the following is applicable to backhoe:-

• Backhoe attachment must be set in the travel position when the front shovel is used.

• The shovel should be lowered to ground whenever the backhoe is operated in poor soils conditions which

could cause stabilisers to sink.

Type

trenchers

Brief about machine

Equipment used to make

trenches


• Correctness of Trenching depths is to be verified immediately before start, especially when working in multi-

service areas.

• Operator should not rely on the clutch slip mechanism which could stop the operation when a boulder is

encountered. He should manually disengage the digging mechanism before attempt of removal of boulders.



PART TWO



Type

loading shovels

Brief about machine

Equipment mounted on

tracks or wheels and

used to excavate loose

soils and other materials,

transport them for short

distances and to load

transporter vehicles.


• Bucket should be carried low during travel.

• Operators must check the rear before and during reversing the machine as for the majority of the time, this

equipment is operated in reverse direction.

Type

graders

Brief about machine

Essentially used as a

shaping and finishing

machine.

High-speed equipment

designed to work on

slopes.


• When working on slopes, special precautions are to be made in presence of wet soil conditions.

• Flags are to be fixed to the blade in addition to lights whenever the grader machine is working on a road

used by other equipment.



PART TWO



14.2.2 fork lifts and telescopic materials handlers

introduction

The following guidance applies, in general terms, to the use of both Rough Terrain Fork Lifts

and Telescopic Materials Handlers. The expression "Fork Lifts" will be used in this chapter to

cover both types of machine.

operators and banksmen

The efficiency and safety in use of fork lifts depends mainly on the competence of those who

control, maintain and operate the equipment.

Operators must.

• Before anyone is permitted to operate a machine for the first time, he must be given off-

the-job basic training by a competent instructor and, at the end of the training, pass a test

on the skills and knowledge required for safe operation in all aspects of fork lift operation.

• A record must be kept which includes the details of basic training given and the nature of

the test. The employee will need a copy of the record, as evidence of training, on change

of employment.

• Employers should not allow personnel to operate fork lifts without written authorisation,

relating to specified types of fork lift.

• Banksmen should be 18 years of age or over and medically fit, with good eyesight,

hearing and reflexes. They should be familiar with any communication systems or signals

used in association with the machine's operation and have been sufficiently trained in the

workings of the fork lift to be able to direct the driver as necessary.

machine stability and safe load handling

Safety in fork lift operation demands that machine stability is maintained at all times. Fork

lifts should, therefore, be carefully selected for the work they are required to do. For

construction sites, only those types designed for site work should be used.

The rated capacity of a machine will be quoted by the manufacturer; but careful checks

should be made to ensure that the capacity is appropriate for the work to be done. For

example, safe loads will be lower if the mast is tilted forward or the boom of a telescopic

materials handler is extended. Stated capacities apply in a static condition and may be far in

excess of those which are safe when the machine is moving. Limits of safe operation will

depend on site conditions and, as far as possible, machines should be operated only on

designated routes.

Even with the right machine for the job and satisfactory site conditions, the safe operation of

fork lifts on site still depends on the machine being properly operated. The establishment of

safe systems of work (in written form where appropriate) and incorporated in operator

training programmes is all important.

When stabilisers are fitted to a machine, they should be used in accordance with



PART TWO



manufacturers' instructions.

When operating fork lifts, drivers must be aware of the effect on the machine's stability of

induced forces. These are the forces which act upon a machine or on its load due to a

change in speed or direction; for instance, when starting, stopping, turning or rolling. The

greater the speed of the machine, the greater these induced forces. Accelerating,

decelerating and braking must be done progressively and smoothly, never hard or jerkily.

Turning must be done carefully, giving due consideration to the weight and placing of the

load and the condition of the ground.

Accident experience has indicated certain points which need particular attention:

• Load stability is crucial and should be checked before travelling.

• Wide loads have tilted and caused fatal accidents. Ensure that loads cannot tip sideways.

• Accessways must be checked to see that they are wider than any load which may be

carried along them. Loads should normally be carried close to the ground but, if they

have to be raised to clear obstructions, they must be lowered when the way is clear. The

operator should be assisted by a banksman.

• The weight of timber and other porous material should be re-estimated if it is wet.

• If the machine has a mast, loads should be lifted with the mast vertical or slightly tilted

back.

• Travelling on slopes, or in poor ground conditions, may be critical and the machine

manufacturer's recommendations should be followed. The danger of skidding and

overturning is particularly serious on two wheel drive machines where braking can cause

weight transfer away from the brake axle when negotiating a slope.

• There are reversing hazards with fork lifts, as with other transport. Audible warning

alarms are a useful aid, but their effectiveness can be limited by general background

noise and by operators relying on them, instead of carrying out a visual check before

reversing. The need for a banksman should always be considered.

Whenever the load impairs the operator's vision, a banksman should be used to guide the

operator.

With articulated fork lifts, a lift should not be made unless the front and back wheels are in

the same straight line.

Unit loads should not be broken down unless the overall weight would overload the machine.

stacking of materials

Stacking areas should be clearly designated and built on firm level ground with good

drainage. There should be adequate clearance between the stack and any wall, because

walls have been known to collapse as a result of the horizontal pressure exerted by the

weight of stacked material.



PART TWO



The stability of a stack depends on:

• Relation of its height to the narrowest base dimension (height should not exceed three

times the narrowest base width).

• Interlocking of the material to prevent movement.

• Compactness and the security of wedging, where applicable, to avoid sideways

movement.

• Proper understanding of the weight to be carried by the components at the bottom of

the stack (this is particularly important where fragile materials are concerned).

• The avoidance of any projecting items which, if accidentally struck, could cause

the collapse of the stack.

• Adequate measures to ensure security in high winds.

Most accidents involving collapse occur during the destacking process, when material is

removed in an uncontrolled order to suit the operator's convenience, thereby leaving

portions standing at a height which cannot be supported by the remaining base. De-stacking

should be in the reverse order of the original stacking process.

safe systems of work - safety of site personnel

On sites operating fork lifts, all personnel must be fully instructed in the safe systems of work

laid down for their protection, and must observe them at all times. Some of the points which

should be covered by safe systems of work are:

• Everyone not directly involved in fork lift operations should keep well clear of the

machine.

• The carrying of passengers on fork lifts should be forbidden.

• Persons acting as banksmen, or guiding the driver in removing his forks from the pallet,

should:

1. keep a safe distance from the machine and its load

2. never stand under the elevated load of a fork lift

3. never stand between the load and any exposed floor edge, or between the load and

a fixed object

4. wear conspicuous clothing; reflective jackets should be worn during poor visibility



PART TWO



attachments

Attachments are designed to increase the

scope of fork lifts. In each case it must be

remembered that the use of an attachment

can radically alter the fork lift's stability

characteristics and hence its safety (see

Fig. 1).

Preferably, any attachment should be made

by the manufacturer of the fork lift, and its

incorporation on the fork lift done in

consultation with them; otherwise it is

essential that the attachment is designed by

a competent person and that adequate

testing is carried out before the equipment is

allowed into general use.

The use of attachments may involve

additional training for operators to ensure

overloading does not occur.

When using a jib/hook attachment, similar

operating procedures to those for mobile

cranes should be employed.

safety devices

Each rough terrain fork lift should have a device incorporated in its hydraulic system which

will not allow the machine to lift weights greater than its rated load. The machine should also

have a device which will prevent a specified load being lifted beyond a given height.

The provision of a simple levelling indicator is strongly recommended, with the danger

zones, where it is not permitted to raise the load, clearly marked. Such indicators, if not

fitted as original equipment, can be fitted by the user; but only after consultation with the

manufacturer of the fork lift.

Every telescopic materials handler should be fitted with an Automatic Safe Load Indicator

which gives a continuous read out of forward stability and sounds an audible alarm when

the load exceeds 95% of the Safe Working Load. Other safety devices which should be

fitted to these machines are:

• a levelling indicator

• check valves which will hold the load in the event of hydraulic pressure loss

• an indicator lamp which will show when stabilisers are on firm ground

Fig. 1 – effect of fork extensions

OUTSIDE LOAD CENTRE - UNSTABLE

WITHIN LOAD CENTRE - STABLE



PART TWO



working platforms

Due to height limitations and the necessity to have an absolutely level surface, the use of

working platforms on fork lifts will be very rare on site.

Where it is intended to use a working platform on a telescopic materials handler; it is

essential that the fork tilt control is isolated to prevent inadvertant operation.

maintenance

Fork lifts should be maintained in efficient state, efficient working order and in good repair.

Details of necessary maintenance will be given in manufacturers' manuals. It will be

necessary to arrange for this maintenance to be carried out, usually involving a fitter to do

the less frequent but more complex work and the driver to do the simple but vital checks.

The driver should:

• check that any defects previously reported to the supervisor have received

attention

• check battery levels, topping up where necessary

• check tyres for wear, damage and pressure

• check fork locating or retaining pins

• check water and oil levels

• check brakes

• check any rollover or falling-object protective structures (ROPS or FOPS), where

fitted

• check that steering is positive

• check the stability of the seat

• check the mirrors and test the horn (it is recommended that these items are fitted)

• check that lights are working correctly

• check working of lift mechanism; check chains for lubrication and for foreign

material caught in links

• check hydraulic hoses for chafing and leakage.

Any defects revealed by these checks should be reported by the driver to his supervisor.

Machines should not be used until defects which affect their safety have been rectified.



PART TWO



14.3 Precautions with some Miscellaneous Mobile Plant

Type

Hydraulic Mechanical

Breakers

Brief about Equipment

Used to break and penetrate

rock or concrete into pieces.


• Ensure that before the start of work that the excavator is in proper working order and capable

of carrying the load of the attachments.

• Only involved persons are to remain close of the breaker and these persons should wear

safety helmets and eye protection.

• The danger of rock/concrete material splintering should always be considered.

Type

Telescopic

Boom Concrete

Pump

Brief about Equipment

Used to pump concrete from

ground to various floors on

buildings under construction.


• Driver/operator must be fully trained in all operational and safety aspects of the plant.

• Outriggers must always be used prior to pumping.

• Communication to be maintained by use of a banksman or radio when discharge hose is out

of sight of the Pump operator.

SECTION 15

SECTION 15

STATIC PLANT & EQUIPMENT

INTRODUCTION 1


15.1 DUTIES 2

15.2 SELECTION 2

15.3 SITING 3

15.4 USE 3

15.5 MAINTENANCE 3

15.6 SAFETY STANDARDS FOR SPECIFIC TYPE OF

PLANT & EQUIPMENT 4

15.6.1 compressors/air receivers & pneumatic tools 4

15.6.2 cement and concrete mixers 5

15.6.3 bar bending and cropping machines 6

15.6.4 burning and welding equipment 6

15.6.5 brick/block saws 6

15.6.6 woodworking machinery 7

15.6.7 winches 7

15.6.8 tirfors 8

15.6.9 hoists 9

15.6.10 drilling rigs 9

15.6.11 piling equipment 10

15.6.12 cement silos 10

15.6.13 batching plants/transmixers 11



PART TWO


ADM/H&S/Pt 2 01 March 2005 STATIC PLANT & EQUIPMENT 1 of 11

SECTION 15

STATIC PLANT AND EQUIPMENT

INTRODUCTION

This section identifies the general principles of selecting, siting, maintaining and using static plant and equipment

commonly found on Building Sites in Abu Dhabi.

The general risks of specific items are also described.


Ministerial Order No. (32) Year 1982 – Article (1), (6), (7) (9), (10) (15),



PART TWO



15.1 DUTIES

15.1.1 employers

Have a legal duty to ensure the proper selection and maintenance of mechanical plant and

equipment, and to provide the required information, instruction and training to their operators

in their safe use

15.1.2 operators

should have been trained not only in the correct operation of the plant and equipment, but

also in the limitations of its use, and the hazards which exist if it is not used properly. It is

recommended that all plant operators hold relevant Certificates of Training Achievement

15.1.3 manufacturers

Have a duty to provide information on any hazards associated with their products and advice

on their safe use. Users should ensure they are in possession of this information, and make

certain that the operators are instructed accordingly.

15.2 SELECTION

The proper selection of static plant and equipment is of paramount importance to reducing

risks in the workplace. The exact requirements for each specific item of plant or equipment

should be determined by risk assessment.

Above anything it should be safe and ‘fit for purpose’.

The following are the main points to consider:-

• location of use and any limitations, eg noise, weight, vibration, fumes, fire risk, etc. that

exist, or will exist.

• space required to safely operate the plant or equipment.

• method in which the plant or equipment will be safely transported to site, safely offloaded

and positioned.

• performance of the plant or equipment to ensure it is capable of performing the task

without being overloaded.

• availability of suitably trained, experienced and competent personnel to operate the

specific plant or equipment.

• any special requirements for guarding.

• if appropriate, whether electric or combustion engine options are more suitable for the

workplace?

• what type of ground conditions are required to support the plant or equipment?



PART TWO



• if appropriate, whether solid tyres are a safer option than pneumatic tyres, or vice-versa?

• if appropriate, what heights are required to be reached?

• is the plant or equipment new. If not, are maintenance details available?

• what maintenance of the specific item is required and how frequently?

• whether the item of plant or equipment can be safely removed from its location after

construction works have progressed?

• will any lifting operations be required to position the plant or equipment? If so, are lifting

eyes available?

15.3 SITING

As previously mentioned, specific items of plant and equipment should be selected with

exact siting (location and suitability) requirements in mind.

In some cases, the area where the plant or equipment is to be sited will need to be

prepared. For instance, ground compaction, level firm surfaces, extract systems, exclusion

zones, sound barriers, etc, may be needed. A risk assessment should be used to determine

the safe method of siting the plant or equipment, taking into account all the hazards from

when it enters the site gate to its final position(s).

15.4 USE

Before any item of plant or equipment is put into operation, it should be assessed to ensure

that it is in accordance with the selection specification, and safe for use.

• all operatives should be trained and/or experienced and competent to safely operate the

plant or equipment.

• no plant or equipment should be used if it is not in a safe working condition.

• all specific safety control measures determined by risk assessment should be in place

before the plant or equipment is used.

15.5 MAINTENANCE

Any item of plant or equipment will remain safe to operate only if it is properly maintained in

good condition. A programme of regular preventative maintenance should be established to

ensure that all plant and equipment is systematically inspected, serviced, maintained and

repaired as necessary. Responsibility for taking this action should be clearly identified.



PART TWO



Personnel undertaking maintenance work should be suitably trained, experienced and

competent to undertake their works safely. Those who are not fully competent, eg trainees,

should be provided with additional supervision.

A safe system of work must be maintained during all maintenance and repair operations

and, where necessary, a permit to work system (e.g. a lock-off system) should be

established to ensure that no part of the machinery is accidentally set into motion whilst

work on it is being carried out. (see Pt 2 section 11) - Permit to Work.

While personnel are carrying out inspections, maintenance or repair tasks, machinery

should be isolated and inspection covers, etc should be securely propped to ensure the

safety of the inspector.

The appropriate manufacturer’s repair and servicing instructions should be made available

to all persons responsible for carrying out the work.

15.6 SAFETY STANDARDS FOR SPECIFIC TYPE OF PLANT & EQUIPMENT

15.6.1 compressors, air receivers and pneumatic tools

The following points should be checked: (see Fig.1)

• V-belt and pulley drive is adequately

guarded.

• air receiver is:-

� clearly marked with its safe working

pressure and distinguishing number.

� is fitted with a safety valve, a pressure

gauge, a drain cock and a manhole.

� has been examined as required by an

approved inspector.

• if an airline is used for blowing out, the

activity is strictly controlled and that the

person using the airline, and other persons

in the vicinity, are adequately protected (e.g.

by eye protection).

• joints in air lines are made with purpose-made connections.

• air supply to all tools is switched off when tools are left unattended or changed.

Under no circumstances should horseplay with air lines be permitted.

Fig. 1 - Type of Compressor used in Workshops, can be either fixed or used as a mobile unit.



PART TWO



15.6.2 cement mixers

The following precautions should be taken when

using cement and concrete mixers: (see Fig.2)

• operatives should be experienced and competent

to operate the mixer. Where the operative is not

experienced, a higher level of supervision will be

required.

• should be sited on a firm level hard standing to

ensure its stability during all modes of operation. A

paved surface, eg concrete, will contribute to the

ease in which the workplace can be maintained in

a safe manner.

• sufficient room will be required around the mixer for easy/local access for materials.

• provision should be made to facilitate the delivery of materials to the mixer workplace

without the need to move the mixer, equipment, or materials.

• workplace should be maintained to provide a safe work environment for the attendant

and those people delivering materials and collecting cement or concrete.

• should be positioned to allow sufficient ventilation for diesel/petrol fumes to exhaust away

from the operation. If area is not sufficiently ventilated, a change of location should be

considered, but if this is not reasonably practicable, an exhaust extract system will be

required.

• all pulley wheels, belts and gears must be guarded as per the manufactures’ standards.

• on diesel/petrol engine mixers, the exhaust should be suitably shielded to prevent burns.

• unless otherwise stated by the manufacturer, the cover lid over the engine/motor should

be closed whilst the mixer is operational.

• fuel tanks should not be filled whilst the engine is running.

• should never be stopped when materials remain inside. Restarting the mixer when it is

loaded poses increased risks to safety.

• should not be loaded beyond its designed limits. If it will not do what is required of it with

reasonable ease, then it is probably not the correct machine for the job.

• oil levels must be regularly checked to prevent overheating.

• care should be taken when operating the wheel. A tight grip is required when unloading

the mixer to prevent the wheel spinning, which can result in arm and hand injuries.

• mixer and workplace should be inspected daily to ensure continued safe working. Any

faults or damage should be repaired.

Fig.2 - Type of te Mixer commonly used on Building Sites



PART TWO



• many diesel engine mixers generate potentially harmful noise levels, especially for mixer

attendants working in the noise for many hours at a time. Risk assessment will determine

what ear defenders are required (if any) and who is required to wear them.

• proper procedure for starting diesel engines with a starting handle should be followed to

prevent thumb/hand injuries.

• attendants should wear suitable gloves whilst handling the mixer (but not for starting it).

gloves used should also be suitable for handling cement, lime and sand.

15.6.3 bar-bending and cropping machines

Hand and power operated bar benders and croppers should be: (see Fig.3)

• used only by authorised persons,

• used only as recommended by the

manufacturer; no attempt must be made to

exceed stated maximum capabilities,

• firmly mounted on a substantial base

ensuring stability in operation,

• fixed at a suitable height to ensure ease of

operation, and reduce the risk of strain or

injury to the operator;

• maintained in a fully serviceable condition,

e.g. pivot pins, ratchets or cutting edges are

not worn,

• located at a safe distance from other site personnel and activities,

• kept clean and lightly lubricated,

• stored, and adequately protected from the weather when not in use.

15.6.4 burning and welding equipment

(see Pt 2 Section 27) - Welding.

15.6.5 bricks/block saws

The brick saw has been used on construction sites for a number of years. It has a number of

advantages over other methods, namely:

• a neat, straight, flat and accurate cut is achieved.

• whilst cutting, the operative stands upright.

• are fitted with a dust suppression system (water), which effectively prevents dust

contamination.

Fig.3- Example of a Bar Bending Machine commonly used in Workshops on Building Site



PART TWO



• fitted with a diamond tipped, steel blade to achieve a constant depth of cut throughout its

long life.

Because of the inherent dangers in using this type of saw, it is paramount that the

following precautions are taken:-

• saw should always be positioned on a firm, level and flat surface to ensure stability.

• cutting operations should be within a barriered off safety zone to prevent others being at

risk from the saw, and provide the operative (who cannot hear other work operations),

with protection from others.

• operative should be suitably trained and competent.

• area surrounding the saw should be kept in a tidy condition to prevent trip hazards whilst

carrying bricks and blocks.

• maintenance of the dust suppression system is of paramount importance to minimise the

risks of the dust created and prolong the life of the diamond tip blade.

• ear defenders should be worn, especially with diesel/ petrol driven saws.

• safety footwear and eye protection is a must.

• hands should be kept a safe distance away from the revolving blade during the cutting

operation.

15.6.6 woodworking machines

(see Pt 2 section 18) - Woodworking machinery.

15.6.7 winches

Checks should be carried out on all winches to ensure that:

• the winch is securely bolted down,

• the lead angle of the rope is as nearly at

right angles to the drum as possible,

• the rope is strong enough and long enough,

with at least two turns remaining on the

drum,

• the driving pinion engages properly and can

be locked in position,

• water and oil are kept out of break linings,

• brakes are adequate,

• a guard is fitted over the driving cogs,

• persons are kept clear when the winch is operating,

Fig. 4 - Helical/parallel gearing type Floor Mounted Winch with enclosed gearing and flange style roller bearing. Up to 26000lb capacity.



PART TWO



• the pawl and ratchet are in good condition.

• hand winches should be registered, inspected frequently, be thoroughly examined,

cleaned and lubricated at regular intervals. (see Fig.4)

15.6.8 tirfors

The following precautions are necessary in the use of a tirfor machine:

• It should never be released whilst under load.

• forward and reverse levers should not be operated

at the same time.

• secure anchorage must be ensured to hold the

applied load.

• only the operating handle supplied with the

machine should be used. Attempt must not be

made to increase leverage, e.g. by placing a tube

over the lever as an extension.

• only the appropriate manufacturer’s shear pins

must be used.

• when using multi-sheave blocks, it must be

ensured that they are suited to the load applied.

• only the specially designed wire rope supplied by the manufacturer should be used.

• it should be remembered that, when using a tirfor machine for pulling purposes, the

necessary pulling effort is not equal to the load being moved. If the operation of the tirfor

is too much for one man, then the work should be stopped and the number of blocks

increased (within the rated capacity of the machine). (see Fig.5)

Fig.5 - Example of a typical Lightweight type of Tirfor having 800kg. Lift – 1250kg. pull and a 20 metre rope, commonly used on Building Sites.



PART TWO



15.6.9 hoists

(see Pt 2 section 19) – Cranes and Hoists.

15.6.10 drilling rigs

Surface drilling rigs, including augers, are

used in the work of site investigation,

sample recovery and testing, well drilling,

and other geotechnical processes such as

ground stabilisation and anchorage. (see

Fig.6)

As all drilling work requires a high degree of

skill and competence, without the overall

supervision normally expected on

construction sites, it is recommended that

formal training of operatives is carried out

followed by on the-job instruction under the

guidance of experienced drillers. This

method provides operatives who are both

knowledgeable and safe.

The proposed site should be investigated prior to any drilling operations, and particular

attention given to such hazards as overhead power lines, underground services, toxic fills,

mine cavities, cellars, derelict buildings etc., which could affect the safe installation and

operation of the drilling rig, and the safety of personnel. (see Pt 2 section 6) – Overhead

and Underground Services.

Permission must be sought from, and notification given to, the various interested bodies and

organisations, such as ADWEA, A.D.N.O.C, S.P.D. before site access or drilling operations

commence.

The working area immediately around the drilling rig should be kept tidy at all times, and any

working platforms, (e.g. on the vehicle-mounted rig) should be uncluttered and free of

grease and oil spillage. Rods, casings etc., should be stored in a safe manner; i.e., pegged

to prevent collapse and spreading

In particular:

• hand tools should be kept in a clean and serviceable condition.

• process of connecting and disconnecting rods and casings should be carried out in a

manner which avoids the possibility of injury to personnel.

• manual lifting of heavy equipment, rods and casings, should be carried out in the

recommended manner.

• loose attire such as scarves, ties and sleeves, and the wearing of wrist watches and

Fig.6 - Example of a Mobile Surface Type Drilling Rig commonly used on Building Sites and Explorative work in Abu Dhabi.



PART TWO



jewellery such as finger rings can lead to serious injury, and should not be allowed.

• wearing of suitable gloves is essential in the handling of drilling equipment, in particular

steel wire rope. In the possible presence of toxic material, the use of protective barrier

cream is recommended.

• safety helmets should be worn at all times.

• when rotary percussive drilling is taking place, ear defenders should be worn.

• in the presence of rock dust, or similar hazards, suitable protection should be taken

against inhalation, ingestion, or damage to the eyes.

• wearing of safety footwear at all times is strongly recommended. (see Pt 2 section 12)

PPE

15.6.11 piling equipment

(see Pt 2 section 23) - Excavation & (see Pt 2 section 26) - Piling.

15.6.12 cement silos

Adequate lifting points must be fitted to facilitate

handling and positioning. Proper ladder access, with

safety hoops where appropriate, must be provided.

Where access to the top of the silo is needed, a safe

working platform must be provided.

A safe system of work must be established to allow

blockages of material to be cleared without the

operative having to enter the silo. When, for any

reason, it is necessary for a person to enter the silo

to carry out work, the Confined Space Requirements

apply. At least two competent people, fully trained in

rescue procedures, including the use of breathing

apparatus, must always be in attendance. Any

person entering a silo must always wear a safety

harness and line and adequate means of rescue

(sheer legs, winch or other means of leverage) must

be provided. (see Pt 2 section 21) -Confined Space.

There must be adequate lighting during the hours of

darkness or when natural light is inadequate. (see

Fig.7)

Fig.7 - Type of Cement Silo complete with pneumatic fill pipe, baghouse for dust control, a full perimeter safety cage and ladder, manhole and pressure relief valve.



PART TWO



15.6.13 batching plant/transmixer

Static concrete batching plants are

now a common feature of large

building sites, and although they

are fairly safe when properly

operated and maintained, there

are inherent dangers such as

concrete dust, moving parts of

machinery etc. (see Fig.8)

The following are the main safety

features to consider:

• only trained and authorised

persons should be allowed to

operate batching plants.

• cement dust from silo to be effectively controlled.

• entry into silo should be under a permit to work system as this is classed as a confined

space. (see Pt 2 section 11) – Permit to Work.

• all moving parts of any machinery should be effectively guarded.

• storage bins storing dry cement stored should be covered by a tarpaulin.

Fig.8 - Sowing a typical example of a static Batching Plant commonly used on large Building Sites.

SECTION 16

SECTION 16

PORTABLE TOOLS

INTRODUCTION 1



16.1 ELECTRIC TOOLS - GENERAL REQUIREMENTS 2

16.2 PORTABLE ELECTRIC SAWS 3

16.3 PORTABLE ELECTRIC DRILLS 3

16.4 PORTABLE ELECTRIC GRINDERS & CUTTING BLADES 3

16.5 CARTRIDGE OPERATED TOOLS 4

16.6 COMPRESSED - AIR TOOLS 5

16.7 HAND TOOLS - GENERAL PRECAUTIONS 7



PART TWO


ADM/H&S/Pt 2 01 March 2005 PORTABLE TOOLS 1 of 7

SECTION 16

PORTABLE TOOLS

INTRODUCTION

The majority of power driven hand tool accidents are caused by improper handling and poor

maintenance of the equipment, both of these can be overcome by good supervision and proper

training of the tool operators.

This section will introduce the legal requirements, and applicable standards that should be adopted

when using ‘Power Tools’ on the Departments Building/Construction sites.

MAIN APPLICABLE U.A.E.LEGISLATION

Ministerial Decision No. 32 of 1982 Articles; (10) – (14)


OSHA 2207, Part 1926, Subpart I, section 1926.300 – 1926.305

British Standard BS 4343, BS 1362, BS 2769

British Standard BS 2092, BS 4481, BS 4078



PART TWO



16.1 ELECTRIC TOOLS - GENERAL REQUIREMENTS

condition of tools

All power tools and similar equipment, whether furnished by the employer or employee, shall

be maintained in a safe condition.

guarding

When power tools are designed to accommodate guards, they shall be equipped with such

guards when in use.

power source

Portable electric tools, when used in normal industrial conditions working off 220/240v power

source, should be in good condition, properly maintained and power supply to the tool fitted

with an approved earth leakage detector. (refer to site electrical requirements section in this

manual section 9) Electricity at Work.

personal protective equipment

Employees using power tools and are exposed to the hazard of falling, flying, abrasive, and

splashing objects, or exposed to harmful dusts, fumes, mists, vapours, or gases shall be

provided with the particular personal protective equipment necessary to protect them from

the hazard. (see Pt 2 section 12) PPE.

housekeeping

Good housekeeping is essential for good workmanship and safety. All tools shall be neatly

and correctly stowed when not in use. Work areas must be maintained in a clean and orderly

fashion.

maintenance

All tools shall be cleaned and inspected regularly, and those which are worn or damaged,

should be replaced or repaired immediately.

operators

Only authorised and competent persons shall be permitted to operate power tools.



PART TWO



16.2 PORTABLE ELECTRIC SAWS

• all portable saws are equipped with a fixed guard over the upper half of the blade and a

moveable guard which automatically covers the lower half of the blade. Both these guards

must be kept in place; blocking of the lower guard to prevent closure is prohibited.

(see Fig.1)

• saw blades shall be regularly checked, kept in good condition and stored suitably.

• blades used must be those recommended for the material being cut.

• if a portable saw is adaptable for bench top use it

must be securely clamped before use to the support

designed for this purpose.

• operators exposed to harmful dust, as when cutting

concrete, tile, lead or stone, should wear approved

type respirators.

• operators should be trained in the use of the electric

saw and be familiar with the hazards associated with

the tool.

• appropriate personal protective equipment must be

supplied by the employer and worn by the employee.

16.3 PORTABLE ELECTRIC DRILLS

• electric drills shall either be of the approved double-insulated type or grounded in

accordance with site electrical requirements section in this manual.

• operators shall be trained in the use of the tool; selection of the bit for the material to be

drilled, use of ‘starter’ marks, clamping of work piece and elimination of loose clothing on

the operator.

• appropriate personal protective equipment for the task and material being drilled.

16.4 PORTABLE ELECTRIC GRINDERS & CUTTING BLADES

(see also Pt 2 section 17) Abrasive Wheels.

• no person shall operate an abrasive wheel grinder unless he is trained and found to be

competent to mount and operate an abrasive wheel or cutting blade and perform the task

safely.

Fig.1 - Portable Electric saw fitted with a spring loaded retractable guard.



PART TWO



• grinding wheels maximum permissible speed should be higher or the same as the grinder

motor.

• the wheel must be inspected and dressed regularly. Appropriate eye shields and

respirators must be worn during the dressing operation.

• cracked stones shall be discarded immediately.

• tool rests shall be used and adjusted properly. The rest should not be adjusted when the

grinder is in motion.

• cutting-off wheels should only be used on machines designed specially for their use –

never use an un-reinforced cutting-off wheel on a portable grinder machine.

• all guards designed for use with a grinder must be used and never removed.

• so far as it is practicable, the work area shall be maintained in good and even condition,

shall be kept clear of loose material and prevented from becoming slippery.

• approved cautionary notices displaying the hazards associated with grinding wheels shall

be posted at the work area where grinding or cutting is being carried out.

• the side of the wheel shall not be used to perform work under any circumstances.

• appropriate approved personal protective equipment shall be used by the operator and

helpers.

• grinding or cutting operations shall be isolated from other activities and personnel by the

use screens or any other approved means.

16.5 CARTRIDGE OPERATED TOOLS

• no person shall operate a cartridge-operated tool or powder-actuated tool unless, he is

trained on the specific tools and found to be; competent in the use of the tool, understand

all risks and hazards associated with the device; and perform the task safely. (see Fig.2)

• additional training must be conducted for other makes and models.

• the operator must undergo a specific test to check for colour blindness.

• all guards designed for use with a cartridge operated shall be used at all times – there

are no exceptions.

• tools and cartridges must always remain in the possession of the person to whom they

are issued. When not in use, they must be locked up in a safe and controlled place. They

must never be left unattended at any location for even the shortest of times.

• used and spare cartridges must be returned to the stores as soon as possible, and must

tally with cartridges signed out.



PART TWO



• the tool shall be examined when taken from the store, before use, and upon return to the

store for defects (by persons competent to carry out those examinations).

• any problems with the tool or cartridges shall be reported to the store keeper immediately

and a record kept for the life of the project.

• the tool must be dismantled and examined for defects (by a competent person duly

appointed and authorised to undertake this duty) every seven days and taken out of

service if any defects are found.

• the tool must always be operated from a firm and stable position. A scaffold is preferable,

but if use of a ladder is unavoidable, the operator must use effective fall-arrest equipment.

Mobile scaffolds must be securely tied to a stable structure.

• full face screen, safety helmet, ear protectors and suitable gloves shall be worn by the

tool operator and by any other worker who might be endangered by flying pins, particles

of materials, sparks, or the noise of firing.

• cartridges must always be kept in the

makers package and never be carried

loose or in a pocket.

• cartridge tools must never be used in any

area where flammable gases, vapour’s or

explosive dusts are present.

• cartridge operated tools will be controlled by a storekeeper, registers and method statements and will be audited by the Contractors safety department and the Client on a regular basis.

16.6 COMPRESSED-AIR TOOLS

• pneumatic tools shall be secured to

the hose or whip by some positive

means to prevent the tool from

becoming accidentally disconnected.

Safety clips or retainers shall be

securely installed and maintained on

pneumatic impact tools to prevent

attachments from being accidentally

expelled. see Fig.3

Fig.2 - Cordless Cartridge Gun fitted

with automatic nail feed and

patent head to prevent nail

penetrating even thin sheets.

Patent Head to prevent over penetration.

Fig. 3 - Showing a “Whip Check” strong steel cable which, when attached to both the hose and tool end, prevents hose whip in case of accidental seperation of coupling or clamp device.

Hose End Tool End



PART TWO



• all pneumatically driven nailers, staplers and other

similar equipment provided with automatic fastener

feed, which operate at more than 100p.s.i.

pressure at the tool, shall have a safety device on

the muzzle to prevent the tool from ejecting

fasteners, unless the tool is in contact with the

work surface. (see Fig.4)

• compressed air shall not be used for cleaning

purposes except where reduced to less than 30

p.s.i., and then only with chip guarding and

personal protective equipment.

• the manufacturers safe operating pressure for

hoses and appurtenances shall not be exceeded.

• the use of hoses for hoisting or lowering tools shall

not be permitted.

• all hoses exceeding ½ “ inside diameter shall have

a safety device at the source of supply or branch

line to reduce pressure in case of hose failure.(see

Fig.5)

• proper fire precautions will be taken with regards to

compressor operations.

• air supply lines shall be protected from damage by

vehicles, materials, etc and should be carried across roads

and walkways by means of an overhead carriage or device

designed for the specific purpose, or in protected channel

ways.

Fig.4 - Showing a pneumatically driven

Nailer/Stapler fitted with safety

device at the muzzle to prevent

tool from ejecting Nails/ Staples.

Fig.5 - Showing types of Safety Valves which can be fitted either at source of supply or branch line in order to reduce pressure in case of hose failure.



PART TWO



16.7 HAND TOOLS - GENERAL PRECAUTIONS

• defective tools shall not be issued or used to perform a task.

• all tools will be stored in storage racks or bins and will be cleaned and oiled to prevent

corrosion.

• cutting edges will be protected during storage, and transporting to work area.

• all damaged or worn tools will be promptly and soundly repaired to original condition. If

tools cannot be repaired on the job, they will be replaced and the damaged tool taken

from site and repaired or destroyed.

• replacement of hammer handles by anything other than original parts is forbidden.

Welded metal handles shall not be permitted.

• mushroomed chisels and cracked or broken chisel handles shall be repaired or replaced.

• appropriate personal protective equipment shall be used when performing work with tools.

SAFETY CHECKLIST - FORMWORK


ADM/H&S/CL/2.16/1 01 March 2005 SAFETY CHECKLIST - FORMWORK & STEELFIXING 1 of 3

Since errors in formwork erection are not always remediable, checking for the correctness of formwork

erection should be scheduled far enough ahead of erection time for the permanent structure. Items to

be checked for the correctness of formwork erection are the following:

General

�� adequate anchorage, levelling and correct positioning of sole plates and grillages are achieved.

�� base plates and grillages should be located to the centre of underlying sole plates.

�� vertical supports checked.

�� vertical alignment should be plumbed within deviation in accordance with specified tolerance.

�� spacing for these members is to be executed in conformance with drawings and standard

details.

�� all members, couplers, fittings, wedges of the formwork and others are installed properly,

secured, tightened and at correct positions. If these precautions are not taken into account,

loose and non-nailed wedges may fall-out in presence of any vibration arising from activities

such as concrete placing and consolidation.

At points of Load Transfer

�� correct details applied as per fig.3.

�� base and head jacks are not over extended unless detailed with adequate special bracing (see

figs. 4 & 5)

�� that steel section web stiffeners are provided as detailed.

�� there is positional accuracy of all members.

�� there are no eccentricities in excess of allowances specified.

Lacings and Bracings

�� all specified members are in place.

�� all bracings and lacings are coupled as close to node points and never more than 150mm away.

�� all bracings and lacings are connected to correct members e.g. diagonals to lacings to allow

right angle structural couplers to be used.

SAFETY CHECKLIST - FORMWORK



required precautions during erection and use of formwork

�� during the construction of large items, suspended slabs with proper guarded edges and suitable

access ladders shall be used.

�� no storage should be placed on formwork since it is not designed to carry additional heavy

loads for other purposes.

�� formwork should be designed to allow safe lifting and handling from points designed for this

purpose.

�� persons not involved in the construction process, dismantling or inspection of formwork should

be denied access.

�� loose materials and plant should be fixed against any movement including lateral movement

induced by high winds.

�� whenever it is possible that workers can fall from slab formwork by more than 2metres, suitable

edge guards shall be installed.

�� whenever workers are erecting formwork elements higher than 2 metres over previously erected

slabs, guarded work platforms with access ways should be provided. These access ways

should be also guarded and wide enough to allow for workers to carry materials (see section 2 -

Scaffolding & Working Platforms)

�� proprietary formwork systems should be erected and used in accordance with manufacturers’

instructions.

required precautions during dismantling of formwork

�� it must be determined ahead whether back-propping before complete release of the formwork or

re-propping after release of the formwork is the method to be employed.

�� for the safety and convenience of workers carrying out the dismantling activity, proper

temporary platforms must be provided.

�� proper tarpaulins or nets should be placed to decrease the danger of any falling material.

�� all dismantled and removed materials shall be immediately stored and properly handled to allow

for its use in the future.

dismantling steps should be carried out in the following sequence:

�� removal of loose fittings and materials

�� removal of projecting nails and sticking elements (in the case of concrete) as work proceeds.

�� before removal of safety guardrails making part of the formwork, replacement safety guardrails

are to be installed and connected to the edges of concrete.

�� after removal, formwork should be supported safely during repair, oiling and other maintenance

works needed before reuse.

SAFETY CHECKLIST - STEELFIXING



Precautionary measures to be taken with steel fixing include the following:

�� steel bundles should never be carried or lifted by the binding wire. Proper slings should be

used.

�� steel fixers should work at safe places or shops provided on site. Persons not involved in steel

shop work should be denied access.

�� during the cutting of reinforcement, protective gloves and eye protection must be worn by

persons performing work.

�� only recommended types of blades should be fitted to disc cutters to prevent any accident

arising from the breaking of a blade.

�� only trained workers are to be authorized to use the disc cutters.

�� torches shall not be used in cutting steel of types adversely affected by heat.

�� the short end of the cut bar should not be left to fly off and endanger life of persons.

�� projecting steel bars should be capped to reduce their risk potential.

�� proper walkways should be installed over the fixed steel cages to secure the safety of persons

crossing over to access their destination.

SECTION 17

SECTION 17

ABRASIVE WHEELS

INTRODUCTION 1

DEFINITION


17.1 DUTIES OF OPERATORS 2

17.2 TRAINING AND APPOINTMENT OF PERSONS TO MOUNT WHEELS 2

17.3 SELECTION OF WHEELS 2

17.4 ABRASIVE WHEEL CHARACTERISTICS AND MARKINGS 2

17.5 MOUNTING OF WHEELS 4

17.6 CUTTING OFF WHEELS 5

17.7 PEDESTAL/BENCH MOUNTED GRINDERS 5

17.8 GUARDS 5

17.9 CONTROLS 6

17.10 GENERAL SAFETY REQUIREMENTS 6

17.11 SUMMARY OF MOUNTING PRECAUTIONS 7



PART TWO


ADM/H&S/Pt 2 01 March 2005 ABRASIVE WHEELS 1 of 7

SECTION 17

ABRASIVE WHEELS

INTRODUCTION

Abrasive wheels are commonly used in the workshop environment, and are potentially dangerous

because of their high speed of rotation, with the resultant possibility of break – up under centrifugal

stress.

For these reasons it is paramount that all personnel who use Abrasive Wheels follow the rules set out

in this section, in especially the wearing of suitable and approved eye protection.

Abrasive Wheels are defined as:-

• a wheel, cylinder, disk or cone which, whether or not any other material is comprised therein,

consists of abrasive particles held together by mineral, metallic or organic bonds whether natural or

artificial.

• a mounted wheel or point and a wheel or disc having in either case separate segments of abrasive

material.

• a wheel, or disc made in either case of metal, wood, cloth, felt, rubber or paper and having any

surface consisting wholly or partly of abrasive material.

• a wheel, disc or saw to any surface any of which is attached a rim or segments consisting in either

case of diamond abrasive particles, which is, or is intended to be, power driven and is for use in

any grinding or cutting operations;


Ministerial Order No. (32) Year 1982 – Article (7), (10), (11) & (12)



PART TWO



17.1 DUTIES OF OPERATORS

• no employed person using an abrasive wheel shall wilfully misuse or remove any guard,

or wilfully misuse any protection flanges , other appliance provided, or any rest for a work

piece.

• every employee shall make full and proper use of guards, protection flanges and any

other safety devices fitted, and if he discovers any defect in the same, shall report such

defect to the manager, or other appropriate person.

17.2 TRAINING AND APPOINTMENT OF PERSONS TO MOUNT WHEELS

• no persons shall mount an abrasive wheel unless he has been trained, is competent, and

has been duly appointed in writing.

• all entries must specify the class or description of the abrasive wheels which the

appointed person may mount, and the person appointed must be provided with a copy of

the entry or certificate.

• the employer may revoke an appointment at any time by a signed and dated entry in a

Register.

17.3 SELECTION OF WHEELS

When selecting a wheel, due account shall be taken of the factors which affect safety.

Selecting the correct wheel for the job is equally important for efficient production and for

safety. As a rough and ready rule, soft wheels are more suitable for hard material and hard

wheels for soft material.

The best policy in selecting grinding plant is to consult manufacturers of machines and

abrasive wheels, and not to experiment without competent advice.

17.4 ABRASIVE WHEEL CHARACTERISTICS AND MARKING

The following are the variable elements in abrasive wheel manufacture and the

standard symbols that are used to designate them:

• abrasive means the abrasive used in the wheel construction. Aluminium Oxide is

expressed as A, Silicon Carbide as C.

• grain size means the size of abrasive grains used as cutting particles. The grains are

classified according to the sieve through which they have passed. The range is

expressed by numbers (coarse 8 to very fine 600).



PART TWO



• wheel grade is generally considered as the tenacity with which the bonding materials

hold the abrasive grains in a wheel. Wheels are graded as ‘soft’ or ‘hard’ according to

this degree of tenacity. The Grade scale is expressed in letters from A (soft) to Z (hard).

• structure means the relationship of abrasive grain to bonding material, and the

relationship of both to the spaces or voids that separate them. The void or spaces in the

structure assist in rapidly removing ‘chips’ from the wheel face, thus eliminating or

choking of the abrasive surface.

• bond type means the bonding material used in the wheel construction, and is

described by letters V (vitrified) B (resinoid) etc.

17.4.1 british standard marking system for grinding wheels

SEQUENCE Prefix

W

ABRASIVE

A

GRAIN SIZE

46

GRADE

K

Structure

5

BOND TYPE

V

Suffix

17

Manufacturer’s

Abrasive Type Symbol

(Use Optional)

Aluminium Oxide - A

Silicon Carbide - C

COARSE

8

10 12

14

16

20 24

MEDIUM

30

36 46

54

60

FINE

80

100 120

150

180

VERY FINE

220

240

280 320

400

500

600

DENSE

1

2

3 4

5

6

7 8

TO OPEN

9

10

11 12

13

14

15 ETC

(Use Optional) V - VITRIFIED

B - RESINOID R - RUBBER

E - SHELLAC

S - SILICATE

Manufacturer’s

Wheel Type

Symbol

(Use Optional)

GRADE

SCALE SOFT MEDIUM HARD

ABCDEFGH IJKLMNOPQRST UVWXYZ

Examples of marks

1. cutting-off wheel intended for cutting metal might be A 30 T B.

2. cutting-off wheel intended for cutting brick might be C 30 T B.

3. a general purpose wheel for use on metal and mounted on a portable grinding machine might be A 163 R 5 B.



PART TWO



17.5 MOUNTING OF WHEELS

wheel speed

• before mounting the wheel, check that the speed of the spindle does not exceed the

maximum permissible speed marked on the wheel.

• it must be remembered that centrifugal force (the ultimate cause of wheel bursts)

increase, not directly with speed, but as the square of the speed. The speed at which the

grinding wheel revolves is, therefore, extremely important.

• It cannot be too strongly impressed that doubling the number of revolutions per

minute of a wheel, increases four fold its tendency to burst. The peripheral speed

is generally used for describing permissible wheel.

flanges

• every abrasive wheel must be mounted between suitable flanges, which should be not

less than one third the diameter of the wheel. The flanges should be recessed on the side

next to the wheel, to ensure that clamping pressure is not exerted near the hole.

• flanges should be of mild steel or other material of equal or greater strength and rigidity.

Ordinary cast iron is not suitable.

washers

Washers or blotters, as they are sometimes called, should be made of compressible material

not more than 1/16th of an inch thick. They should be used between the wheel and the

flanges whenever the clamping surfaces are flat, but not otherwise, as in the instance of

taper sided or dovetailed abrasive wheels.

starting new wheels

• before running the wheel make sure the guard is in proper adjustment.

• if the machine is fitted with a work rest, adjust this as close as possible to the surface of

the wheel, rotate the wheel by hand to make sure it is clear all the way round.

unacceptable practices

The following unacceptable practices increase the liability of the wheel to fracture because

they result in excessive stress concentrated near the hole:

• paper washers not used between the wheel and the flanges.

• flanges not recessed.

• flanges unmatched in outside diameter and diameter of recess.

• one flange omitted and the nut tightened directly against the wheel.

• the use of an ordinary steel washer as a substitute for a properly recessed flange.



PART TWO



17.6 CUTTING-OFF WHEELS

• only be mounted on machines designed specially for their use.

• wheel must be of the reinforced type.

• flanges should be as large as practicable

and never less than one third of the wheel

diameter. It is most important that the

flanges should be equal diameter.

• use of unequal flanges is liable to cause distortion and breakage of a cutting-off wheel.

(see Fig.1)

17.7 PEDESTAL/BENCH MOUNTED GRINDERS

• manufacturers safe operating and mounting procedure must be followed.

• check the rated speed of the machine and peripheral speed of the wheel labelled by the manufacturer.

• check for any crack or defect in the wheel.

• tool rest must be provided and the gap between tool rest and wheel shall not exceed 1/8

th of an inch.

• apply only regulated pressure on wheel. Never take too heavy a cut.

• allow wheel to run for a minute before starting grinding.

• grinding must not be done at sides of wheel.

• screen of toughened glass should be provided to protect operators eyes. (see Figs.2&3)

17.8 GUARDS

• guards shall be securely attached to the body of the machine.

• for straight-sided wheels, the maximum angular

exposure of the abrasive periphery and sides shall not

exceed 180°. (see Fig.4)

• guards for straight grinding machines shall be

provided with a front curtain, which shall be securely

fastened to the body of the machine.

Fig. 4 - Front enclosed Guard for Straight Sided Wheels

Fig. 1 - Flange Assembly for a Depressed Centre Wheel.

Tapered Surface

Figs.3 - showing framed type guard for pedestal/bench mounted grinders.

Fig.2 - Showing open perspex type guard for pedestal/bench mounted grinders.



PART TWO



• for cup wheels, the back face and periphery shall be enclosed, and the guard shall be

adjusted to compensate for the wear of the wheel.

• for depressed centre grinding wheels, the wheel shall

have a maximum angular exposure of 180° and the

guard shall be located as to be between the operator

and the wheel during use. (see Fig.5)

• the clearance between the inside of the guard and the

periphery of the unused wheel, shall be not greater than

5% of the nominal wheel diameter.

17.9 CONTROLS

• machines in which abrasive wheels are used must be provided with efficient devices for

starting and cutting off power, and the controls of such devices must be readily and

conveniently operated by the person using the machine.

• while the wheel is in motion, they must be properly secured and adjusted so as to be as

close as practicable to the exposed part of the abrasive wheel.

17.10 GENERAL SAFETY REQUIREMENTS

17.10.1 floors

Floor surrounding every fixed machine or area where portable tools are being used, shall be

maintained in good and even condition. So as far as practicable it will be kept clear of loose

material and prevented from becoming slippery.

17.10.2 cautionary notice

An approved cautionary notice of the hazards arising from the use of abrasive wheels shall

be affixed in every room where grinding or cutting is carried out.

17.10.3 eye protection

Persons carrying out dry grinding operations, truing or dressing an abrasive wheel, must

wear suitable eye protection, or be protected by suitable transparent screens, (see Pt 2

section 12) for further information on PPE.

Fig.5 - Showing Correct Size Guard for Depressed Centre and Cutting off Wheels.



PART TWO



17.11 SUMMARY OF MOUNTING PRECAUTIONS

Given proper equipment, safety largely depends on the few simple rules previously

mentioned and summarised below: -

• before mounting, all wheels should again be closely inspected and ‘rung’ to make sure

that they have not been mishandled in transit or storage.

• wheel mounting should be carried out only by competent and authorised persons.

• the bush, if any, should not project beyond the side of the wheel.

• care should be taken to ensure that all wheels, washers and flanges are free from foreign

matter. Any burrs should be taken off flanges.

• washers of compressible materials not over 1/16th of an inch, should be fitted between

the wheel and its flanges where the surfaces are flat.

• wrinkles in washers should be avoided. Washers are not recommended for taper and

dovetail wheels.

• when tightening nuts, care should be taken to tighten them only just enough to hold the

wheel firmly. Excessive clamping pressure is liable to damage the wheel.

• the nuts should be tightened by hand pressure on a spanner and never by a hammer and

chisel or similar means.

• when the flanges are clamped by a series of bolts, care should be taken to screw up

each bolt uniformly. All the bolts should first be run up with the fingers and then tightened

in pattern formation afterwards.

SECTION 18

SECTION 18

WOODWORKING MACHINERY

INTRODUCTION 1


18.1 GENERAL SAFETY REQUIREMENTS 2

18.2 CIRCULAR SAWS 3

18.3 HAND HELD CIRCULAR SAWS 6

18.4 CHAIN SAWS 6

18.5 TRAINING 7

WOODWORKING MACHINERY SAFETY CHECKLIST

(ADM/H&S/CL/2.18/1)



PART TWO


ADM/H&S/Pt 2 01 March 2005 WOODWORKING MACHINERY 1 of 7

SECTION 18

WOODWORKING MACHINERY

INTRODUCTION

Many accidents on different types of woodworking machinery are reported in the Building Industry.

Woodworking machine cutters can inflict very serious injuries and it is essential that all the precautions

for guarding them are strictly observed.

Neglect or ignorance of the safety rules governing the use of such machinery creates the conditions in

which accidents occur.

Everyone who operates woodworking machinery must understand and comply with the safety

requirements outlined in this section.


Ministerial Order No.(32) Year 1982 - Article (10) to (12)

Ministerial Order No.(32) Year 1982 - Article (14) to (17)



PART TWO



18.1 GENERAL SAFETY REQUIREMENTS

18.1.1 duties of employed persons

• employees using woodworking machines must use and keep properly adjusted all guards

and other safety devices, and use push-stick spikes, push blocks, jigs, holders,

backstops, and any other safety devices provided.

• they must report to responsible persons any defects in machinery, guards, devices or

appliances, and any damage or defects in the surface or ground around the machine.

18.1.2 working environment

• sufficient clear and unobstructed space to be provided around machine to allow work

without risk of injury.

• floors to be level, in good condition, free of loose material, (which includes chips, shaving

and saw dust) and not slippery.

• adequate natural or artificial lighting must be provided for the work being done on each

machine.

• where artificial light is provided it must be positioned, or shaded, to prevent glare

affecting the operator.

• where persons are likely to be exposed continuously for eight hours to a sound level of

90dB(A) or more, ear protectors must be made available and used, and all reasonable

measures taken to reduce noise levels. see section 24 – Noise at Work.

18.1.3 exhaust extraction

Extraction equipment should be provided for planers and other specified machines to convey

chips and particles from cutters into suitable receptacles.

18.1.4 maintenance

• saw blades must not be cleaned while in motion.

• all machines must be of good construction, sound

material, and properly maintained.

• unless hand-held, they must be level, and fixed

securely to a substantial structure which ensures

their stability.

18.1.5 controls

• every machine must be fitted with start and stop

controls which can be quickly and easily controlled

by the operator. (see Fig.1)

Fig.1 - Showing an emergency stop fitted at knee height to a fixed circular saw.



PART TWO



Exhaust outlet

Table

Cross – Cut

Fence

Exaust

Outlet

Saw

Guard

Riving Knife

Extension

Table

18.1.6 guarding cutters

Cutters can include saw blades, chain cutters, knives, boring tools, detachable cutters and

solid cutters, and the following are the main safety points to consider:-

• must be guarded to the greatest practicable extent, having due regard to the work being

done.

• guards to be of substantial construction, properly secured and adjusted, and constantly in

position while cutters are in motion.

• no adjustment may be made to any guard while cutters are in motion, unless safe means

(i.e. mechanical adjusters) are provided.

• allowance can be made for the development of alternative safeguards for cutters

providing these are effective.

• all moving parts, other than cutters, must be guarded.

18.2 CIRCULAR SAW

(see Fig.2 - an overview of all the safety requirements for a floor mounted circular

saw)

Rip fence

Push Stick

Fig.2 - Example of a Floor Mounted Circular saw Fitted with all the Safety requirements.

Emergency

Stop



PART TWO



riving knife (splitter or spreader)

(see Fig.3)

• securely fixed below machine table level, behind and

in line with saw blade.

• must be strong, rigid, smooth and easily adjustable.

• radius of knife not to exceed radius of largest saw

blade for which machine is designed.

• adjusted as close as practicable to saw blade; gap

between knife and blade not to exceed 12 mm at table

level.

• in the case of a parallel plate saw blade, the knife must

be thicker (usually about 10%) than the plate of the saw

blade.

• where the diameter of the saw blade is less than 600mm, the top of the knife should not

be more than 25mm below the top of the blade. knife must extend at least 225mm above

the table.

top guard (crown guard) (see Fig. 4)

• guard to be strong and easily adjustable.

• adjusted to extend from top of riving knife

to a point as close as practicable to the

surface of the material being cut, or, to a

point not more than 12mm above the

material being cut where squared stock

is being hand fed.

• the guard should have flanges on either

side of the blade and be adjusted so that

these extend beyond the roots of saw

teeth. Where the guard has an adjustable

front extension piece, it must be flanged

on the side remote from the fence, and

adjusted to extend beyond the roots of

saw blade teeth.

Fig.3 - Showing position of Riving Knife

Fig.4 - Showing an example of an adjustable Guard fitted on a Circular Saw together with a dust extraction unit.



PART TWO



size of saw blade

• saw benches with a one-speed spindle must not use a saw blade less than 60% of the

diameter of the largest saw blade the bench is designed to use.

• in the case of saw benches with more than one spindle speed, the blade must not be less

than 60% of the diameter of the largest blade the machine is designed to use at fastest

spindle speed.

• a notice must be displayed on the machine specifying the smallest diameter saw blade to

be used in compliance with the above provisions.

limitations on use

• no circular saw may be used for cutting any rebate, tenon, moulding or groove unless the

cutter above the table is effectively guarded.

• the saw blade teeth must project right through the upper surface of the timber at all times

in any ripping operation.

• circular saw must not be used for cross-cutting logs unless the material is firmly held by a

gripping device secured to a travelling table.

push sticks

be available for use on every hand-fed circular saw, and used to:

• feed material throughout any cut of 300mm

or less.

• feed material during the last 300mm of any

cut more than 300mm in length.

• remove cut material from between the saw

blade and the fence. (see Fig.5)

removal of material

• assistants employed to ‘take-off’ cut material may only stand at the delivery end of

machine.

• where this operation must be performed, the delivery end of the machine table must

extend (over its whole width) at least 1200mm from the up-running part of saw blade.

Not applicable to machines which have a roller table or a travelling table, or to

portable machines with a maximum blade diameter of less than 450mm.

Fig.5 - Example of a Push Stick



PART TWO



18.3 HAND HELD POWER CIRCULAR SAWS (see Fig.6)

Modern machines are fitted with guards that completely enclose the saw blade, The depth of

cut is adjusted by altering the position of a moveable shoe or plate in relation to the saw.

For bevel cutting, the shoe may be set at an angle to the plane of the saw.

before using the saw, ensure that :

• correct type of blade is used for the material to be cut.

• blade is in good condition, not cracked or damaged

• blade will rotate in the correct direction

• depth of cut is adjusted so that the saw blade only just

projects through the underside of the material being

cut.

• guard which covers the saw blade shoe is designed to

retract as the blade enters the material.

• It must never be tied back or rendered inoperative

during sawing.

• guard operates freely before using the machine.

• on/off switch is in good working order.

• sheet material is properly supported before cutting.

18. 4 CHAIN SAWS (see Fig.7)

All workers who use a chain saw should be

competent to do so. The operator should have

received appropriate training and obtained

relevant certificates of competence

It is recommended that all chain saw operators

have regular refresher/updates training every

2-3 years.

preparing to use a chainsaw

operators should check:-

• all nuts and screws etc. are tight.

• saw chain is correctly tensioned

• throttle cannot be squeezed unless throttle lock – out is pressed

• operators are wearing the correct PPE.

Fig.6 - Example of a Hand Held Electrically operated Circular saw complete with spring return guard.

Fig. 7 Example of a type of Chain Saw commonly used on Building Sites.



PART TWO



when starting a chainsaw

operators should:-

• place the saw on level ground

• secure saw firmly, e.g. put a foot on the rear handle base plate and a hand on the front

handle.

• set the controls as recommended by the manufacturer.

• pull the starter cord firmly.

18.5 TRAINING

No person should be employed on a woodworking machine, unless he has been trained and

instructed in its operation. Training should include:

• instruction on all machines the person is likely to operate and the types of work to be

undertaken on completion of training.

• instruction on the provisions in the law on Woodworking machines and the methods of

using guards, devices and appliances required by the law must be included.

• emphasise the dangers connected with the use of such machines.

SAFETY CHECKLIST - WOODWORKING MACHINERY


ADM/H&S/CL/2.18/1 01 March 2005 SAFETY CHECKLIST - WOODWORKING MACHINERY 1 of 3

General

Operatives

�� keep a list of authorised operatives.

�� only trained operatives may work without supervision.

�� operatives fully aware of requirements of woodworking machinery law and procedures for

testing new employees.

�� adequate training given on types of machine used and kinds of work done.

�� provided with all necessary equipment – including goggles, ear protectors, face masks and

other protective equipment where required.

Machines and surrounding area

�� stop/start controls easily reached and operated.

�� cutters guarded to greatest extent practicable.

�� machine level and securely fixed to ensure stability.

�� Machine of sound construction and properly maintained.

�� sufficient space around machine for safe working.

�� floors to be level, in good repair, free of loose material and not slippery.

�� adequate natural or artificial light without glare.

�� noise levels reduced as far as practicable – ear protection available where required.

�� extraction equipment provided for chips and particles.

�� extraction of fumes where necessary.

�� fire extinguishers of correct type immediately available, and personnel trained in use.

Circular Saw

Riving knife

�� secure, sound condition, easily adjustable.

�� radius correct and in line.

�� gap between knife and blade correct.

�� knife of correct thickness.

�� height correct for saw blade fitted.




Fence

�� correctly adjusted and secured.

Top guard

�� sound; easily adjustable.

�� adjusted correctly for work being done.

�� flanges either side of blade extend below roots of saw teeth.

Feeding work

�� gripping device in use for cross-cutting logs.

�� push sticks or push blocks available and in use.

Saw blade

�� in good condition – sharp, no cracks; not less than smallest diameter permitted.

�� notice fixed to machines specifying smallest diameter permitted.

�� projects through upper surface of timber when ripping.

�� above table effectively guarded when rebating, tenoning, moulding or grooving.

Front extension guard

�� adjusted to give maximum protection and cover teeth.

Bottom guard

�� blade guarded below table (open frame machines).

Taking off

�� delivery table to extend 1200mm from up- running part of saw blade.

�� assistant correctly positioned.




Hand Held Circular Saw

Operative

�� trained in correct use.

�� no loose clothing, tie. etc.

�� aware of legal requirements

Prior to use

�� machine and plug compatible with supply.

�� leads, plug and switch undamaged.

�� correct type blade for work.

�� blade in good condition, sharp and not cracked.

�� effectively guarded, above and below shoe plate.

�� check condition and function of spring loaded bottom guard.

�� blade securely fitted to rotate in the correct direction (teeth upwards at front end of saw towards

shoe plate).

�� adjust fence (if used) to correct dimension.

�� saw adjusted to correct depth and angle before use, with teeth projecting just through underside

of the material.

During use

�� material being cut adequately supported.

�� use fence or straight edge as a guide; ensure clamps do not impede movements of saw.

�� sufficient free cable on saw.

�� correct stance – behind and in line with saw.

�� work area clear and free of obstructions.

�� protective equipment in use.

�� operator not to be distracted.

SECTION 19

SECTION19

CRANES & HOISTS

INTRODUCTION

MAIN APPLICABLE U.A.E. LEGISLATION 1

19.1 KEY PERSONNEL AND DUTIES 2

19.2 PREPARATION AND PLANNING 3

19.3 CRANE SELECTION 4

19.4 SAFETY PRECAUTIONS BEFORE ERECTION 11

19.5 LOAD RADIUS INDICATORS 15

19.6 GENERAL OPERATING PROCEDURE 16

19.7 INSPECTION, EXAMINATION & TESTING 17

19.8 HOISTS 18

19.9 APPROVED CRANE SIGNALLING SYSTEM 24

MOBILE & TOWER CRANE SAFETY CHECKLIST

(ADM/H&S/CL/2.19/1)



PART TWO


ADM/H&S/ Pt 2 01 March 2005 CRANES & HOISTS 1 of 24

SECTION 19

CRANES & HOISTS

INTRODUCTION

Cranes and Hoists are used extensively on most building site, and although they each have their

different role, they are both primarily used to lift/transport men and material safely from ground level to

various levels and areas on a building site.

This section of the manual gives not only the safety standards required to select, erect, operate and

maintain this type of equipment, but also gives advice and guidance on how to achieve this, it is

therefore imperative that all contractors follow the standards and guidance outlines in this section

result of which will ensure the safe lifting of both men and materials at all times.

.



In compliance with Municipality Traffic Section Regulation



PART TWO



19.1 KEY PERSONNEL REQUIRED & DUTIES

19.1.1 appointed person

A person should be appointed by management to be responsible for the organisation and

control of lifting operations.

The person so appointed should be given adequate training and possess the relevant

experience to carry out the following duties:

• make an assessment of the lifting operation

• plan such operations and select the most suitable lifting appliances, gear and equipment.

• consult with other responsible persons and coordinate lifting operations,

• ensure that adequate inspection and maintenance procedures are in effect for the

selected plant and equipment

• ensure that procedures exist for incident and defect reporting.

19.1.2 crane driver

It is the responsibility of management to ensure that the appointed crane driver has been

properly trained, is competent and fully conversant with all aspects of safe crane operation.

In particular, he must be familiar with the controls and capabilities of the machine that he is

to drive. It is recommended that all crane drivers hold valid Certificates of Training

Achievement issued by a recognised training organisation.

crane drivers should meet the following requirements:-

• must be at least 18 years of age and should be sufficiently mature to undertake the duties

involved.

• possess a valid U.A.E. driving license.

• be medically fit for the purpose, with particular emphasis on eyesight, hearing and re-

flexes, and have a head for heights. (Periodic medical examinations are advised).

• have an aptitude for judging distance, height, speed and perspective.

• be physically capable of operating the controls efficiently without undue fatigue.

• trained in the general principles of crane operation and specifically in the type of machine

he is required to operate.

• trained sufficiently in the mechanics of his machine to be able to carry out routine

maintenance if required by his employer and to identify and report defects.

• trained in the hand-signalling system (approved signalling system is shown at the end

of this section)

• be familiar with the fire appliances fitted to the crane.



PART TWO



19.1.3 signaller / slinger

A signaller/slinger should be appointed by management to ensure clear and precise

commands are given to the crane driver so that no doubt can exist as to who is controlling

the lifting sequences.

Signallers should be readily identifiable to all concerned in lifting operations, (e.g. by wearing

a helmet in a distinguishing colour, or a high visibility jacket).

signallers/slingers should meet the following requirements:

• must be at least 18 years of age.

• be medically fit for the purpose with particular emphasis on eyesight, hearing, and

reflexes.

• have an aptitude for judging distance, height and clearance.

• be agile and strong enough to handle lifting gear.

• be trained in the general techniques of slinging.

• be capable of selecting lifting gear suitable for the loads to be lifted, and to identify

defects.

• have a sensible knowledge of the safe working loads at the various radii of the crane.

• be capable of directing the safe movement of the crane and its load to maintain the safety

of all personnel.

• be thoroughly trained in a hand-signalling system, and be capable, where necessary, of

giving clear and distinct instructions over radio or similar signalling systems. (approved

signalling system is shown at the end of this section)

19.2 PREPARATION AND PLANNING

All lifting operations should be carefully planned and a safe system of work developed. The

safe system should be suitably communicated to all those who are involved with the

operation in any way.

Planning should consider a wide range of factors including the selection of lifting appliances

and gear.



PART TWO



this will be determined by:

• the load to be lifted, including the slings, shackles, blocks and other lifting gear.

• the radius of operation and height of the lift.

• the presence of any restrictions in the form of overhead cables or lifts inside buildings,

etc.

• visibility of the load throughout its travel

• method of attaching the slings.

• appointment of trained supervisors and operatives.

• positioning of the crane, taking account of ground conditions and proximity hazards.

• any necessary erection and dismantling of the crane.

• method of signalling to be used.

• maintenance of lifting appliances and gear.

19.3 CRANE SELECTION

It is important to select the most suitable crane type for the work in hand. Selection of the

wrong crane can produce not only difficulties on site, but also circumstances which may

tempt site personnel to resort to malpractice in order to expedite the work.

Initially the appointed person will have to select the type of crane most suited for the work in

hand. Each type of crane has certain features which usually dictate the most suitable for a

particular application.

19.3.1 mobile cranes

There are three types of mobile cranes:-

• Self propelled, (wheeled type)

• Truck mounted

• Crawler mounted

Mobile cranes are most suitable where the job duration is short and good mobility is required

around the site or between sites. Very few mobile cranes have pick and carry duties;

therefore they normally must be set up on their outrigger base at each lifting location.



PART TWO



self propelled wheeled mobile crane:

Wheeled mobile cranes normally have the

capability to travel with a load, but again they

require firm level ground for lifting operations.

Where maximum mobility is required between

lifting operations, and for use on hard surfaces

such as a stock yard or stores area, they are

ideal. (see Fig.1)

truck mounted crane

Telescopic boom truck – mounted cranes offers

great advantages in their comparative ease of

rigging. They enable lifts to be carried out quickly

and efficiently where the job duration is short and

mobility around site is necessary. In most cases,

these machines are designed for use on metalled

or made up roads and are not for use on soft

ground. (see Fig.2)

Most truck mounted cranes have severely limited

free-on wheels duties, and in many cases, are not

suited for work which requires lifting and carrying.

The majority of work will be carried out on

outriggers, and it is of utmost importance that

these are extended to their correct position. Most

cranes now have lines or arrows marked on the

outriggers beams, to clearly indicate when they are

in the correct position, and should not be used

other than on those settings. (see Fig.3)

Fig.1 - Self propelled wheeled

mobile crane.

Fig.2 - Truck Mounted Crane

Fig.3 - Showing Outriggers extended to their correct length - and Spreader plate provided to distribute load evenly.



PART TWO



crawler cranes

Are best in off road positions where ground

conditions are not suitable for wheeled

cranes. They do however, require a firm

hard level standing where they are to

carry out lifting duties. Transportation

and rigging times are normally longer

with crawler cranes than mobile, and

therefore work duration is another factor

to be considered. (see Fig.4)

19.3.2 tower cranes

Any tower crane selected for use on site should he

chosen with full knowledge of maximum load, and

load at maximum radius requirements with a working

margin in reserve in respect of load, radius and

maximum hook height. (see Fig.5)

siting the crane:

Once a building or structure is finished, a tower crane

has to be dismantled, this factor should always be

taken into account when deciding its initial position.

gradients:

Bases for tower cranes (static or rail mounted) must be

properly designed and well drained. Manufacturer’s

recommendations on the maximum permitted gradient

should be strictly observed.

proximity hazards:

Sufficient clear space for the length of the jib involved should always be provided as with

other cranes nearby, overlapping of jibs can create a special problem. Jibs and counter jibs

might touch and it is essential, therefore, to have a height differential.

Consideration should also be given to the proximity of other structures, buildings, houses,

(including the possible violation of their air space), Public access areas like highways should

always be checked with the owners or appropriate local Utility.

Note: There is now a new Ministry of Labour directive that in future, Tower Cranes will be

required to be sited so that neither the boom nor the jib part of the crane will overhang

onto main streets or any other buildings.

Fig.4 - Crawler type Crane

Fig.5 - Typical type of Tower Crane used on Building Sites in Abu Dhabi



PART TWO



erection precautions:

The erection of a tower crane requires personnel with a good head for heights, specially

trained, and experienced in the particular type to be assembled working under the control of

a trained and competent supervisor.

Insistence must be placed upon the use of safety harness and the wearing of safety helmets

should be enforced where appropriate.

checks before erection commences,

• company carrying out the erection is approved and licensed by the Municipality.

• that foundations for a static crane, the track for a travelling crane, or the supports for a

climbing crane, meet the detailed requirements of the manufacturer, or engineer.

• crane selection in erecting a tower crane should be adequate for any lift involved,

therefore the weight of each component (and its centre of gravity) determined, and

sufficient margin allowed for error.

• suitability of all lifting gear should be carefully considered, particularly in terms of

clearance height, its weight, together with any attachments, should be included in the

load.

• local weather and wind speed forecasts should be obtained from the Meteorological

Office and erection should only take place if the wind speed is within the limit quoted in

the manufacturer’s instructions for erection.

• erection areas should be kept

clear of non-essential

materials, equipment and

men. Before transferring any

large crane section from one-

plane to another (e.g. from

horizontal to vertical) a check

should be made that no loose

items (tools, bolts, etc.) have

been left — falling objects

are dangerous.

• where cranes are being

erected beyond free standing

heights, consideration must

be given to the design and

fitting of the frames, and

anchorage points to nearby

buildings or solid structures.

Fig.6 - Tower cranes should be tied back to the main structure at the recommended intervals. 1. Ties (struts) 2. Braces as per maker’s instruction. 3. Tie frame. 4. Crane Tower. 5. Wedges as per makers instruction. 6. Ladder with safety back hoops.



PART TWO



• concrete structures used for anchorage should be allowed to harden long enough to

acquire sufficient strength to take the loads imposed on the ties of climbing cranes. (see

Fig.6)

• rail mounted cranes should be operated in a fixed position or tied in. Secure stops

should be fitted to the rails in close contact with the bogies to eliminate all longitudinal

movement.

• at each stage of erection, the correct amount of ballast and counter-weight must be

properly positioned. On many cranes, the counter-weight is set in place on the counter-jib

before the main jib is erected.

• weight for ballast and counter-weight, as supplied by the manufacturer, should be marked

with their weight and secured in position to prevent accidental displacement and damage.

• ballast charts, showing the amount, distribution and unit weights of ballast used, must be

fitted to the crane base. Charts must be sited on the crane where they can readily be

seen at all stages of construction work.

• safe means of access must be provided to the cab and throughout the structure for the

purpose of inspection and maintenance. Access to the cab will be achieved using a

permanent steel ladder fitted with safety hoops and provided with rest platforms at 9m

vertical intervals.

• jib inspection may be afforded by the provision of an expanded metal walkway inside the

jib with life lines fitted to permit the fixing of safety harnesses, or by the use of an

inspection cage suspended from the jib or fitted to the saddle.

• wind speed indicators, visible in, or from the driver’s cabin, and at the base of the crane

should be fitted, and If the wind velocity registered is near the manufacturer’s safe

working limit, the crane should be placed out of service.

• automatic audible alarm must be fitted to sound when rail mounted cranes travel.

• warning lights should always be fitted where the top of the crane exceeds 150m above

local ground level and may be required where the obstruction exceeds 90m.

rail tracks - special notes:

base

• should be calculated from the maker’s given loading figure on any one bogie under the

worst conditions and the known bearing capacity of the ground.

track

• must be laid to an accuracy of 6mm in gauge and the maximum slope either along or

across the track should not exceed 1 in 200 metres, unless recommended by the

manufacturer. Curved track can be used for most crane rails, but special precautions are

required to prevent distortion - steel tie rods must be fitted to stop tendency to spread;



PART TWO



curved fish plates should be used. A watch should be kept for any tendency of wheel

flanges to climb the rails

• where laid on a concrete base, the concrete should be level and strong enough to

stand the loading. Thin hardwood, grout or dry pack should be used between rails and

concrete to prevent the holding bolts from becoming loose as the rails bed down.

• when laid on timbers, it is preferable for these to be of rectangular section, set

longitudinally so that the rail itself does not have to act as a bridge between adjacent

sleepers. (Crane tracks have very different loadings from railway tracks.) If longitudinal

timbers need further support or load spread, timber sleepers should be set under - and

in direct contact with them. For levelling purposes, softwood packing is totally unsuitable.

• should be straight or true to curve, slightly but not excessively worn, and be free from

holes burnt in the web, and holes in rails should always be drilled (burning makes the

rails too brittle). Rails should preferably be bolted to timbers and bolts kept tight. (Dogs

or spikes are not recommended.)

• must be perfectly level on curves, radii of curves will be specified by the crane

manufacturer and track layouts should be set and thoroughly checked by competent

engineers.

• area between must be kept clear of all materials and other obstructions, effective steel

wheel stops should be clamped at the end of the rail tracks with sand boxes, or

alternative method of retardation fitted in front.

• earthing must be effective and provide electrical continuity between individual rails. Fish

plates are not enough to give electrical continuity. The resistance between rail and earth

should never exceed 1 ohm.

• deflection of rail track under full load should never exceed 3mm.

• Where practical, outriggers can be extended and the feet kept just clear of the ground for

added safety, but care must be taken to ensure that the outriggers do not foul the ground

or any obstacle.

19.3.3 excavators used as cranes

Any excavator which is to be used as a crane and has a safe working load (SWL) greater

than one ton, must have check valves fitted to the boom and outward reach side of the

stick/dipper.

main safety requirements

• lifting must be done with the stick/dipper in the outward reach mode only.

• if to be used as a crane without any restriction and with a variable SWL greater than one

ton, be fitted with an automatic safe load indicator and be subject an annual test and

thorough examination, or,



PART TWO



• if to be used solely for work immediately connected

with an excavation and with a fixed SWL greater than

one ton have on site, a “Certificate of Exemption.”

• must have the SWL marked on the machine or

displayed in the cab.

• point of attachment for lifting slings, etc. must be

considered with great care.

• slings, for example, must not be hooked on to a

bucket tooth, but must be properly secured to a

correctly designed and manufactured lifting point.

(see Fig.7)

19.3.4 lorry mounted cranes

It should be borne in mind that lorry loaders are primarily an

accessory to a payload carrying vehicle and are designed as

such: nevertheless they are classed as cranes.

As with other jib cranes, lorry loader cranes with a maximum

safe working load (SWL) of one tonne or less are exempt

from the requirement for automatic safe load indicators

(ASLIs) to be fitted. Additionally, no lorry loader crane

requires an ASLI provided that it is used solely for the

purpose of delivery or collection of goods to or from a site.

(see Fig.8)


• siting of lorry loader should take account of the ground conditions which should be firm

and level.

• there should be space for extension of outriggers.

• consider proximity of overhead cables and underground services.

• safe working load of the equipment in relation to any loads being lifted.

• any effects of local weather eg. strong winds

• loads should always be lifted smoothly to prevent them from swinging.

19.3.5 hired cranes

Notwithstanding any advice the crane owner may have offered concerning the selection of a

particular crane or any other relevant matter, the responsibility for ensuring that a hired

crane (or a crane on loan) is of suitable type, size and capacity for the task being

undertaken, and for planning the operation, remains with the user of the crane.

Fig. 7 – Showing Lifting hook welded underside of bucket, fitted with a safety catch eliminating the need to use bucket teeth as lifting points

Fig.8 - Showing a Hiab 250 Type Lorry Mounted Crane having a maximum jib length of 76ft.



PART TWO



19.3.6 scaffold cranes

These small cranes, commonly known as

scaffold hoists, must comply with as

much of the general requirements of

cranes as are applicable, and be secured

to the scaffold in accordance with the

manufacturer’s instruction. (see Fig.9)


• mounted either on tubular supports which

clip to scaffold over them.

• standards to which they are fitted should be

additionally braced to take extra strain.

• loads carried on scaffold cranes should be such that they cannot protrude into the

scaffold structure and become dislodged and, to that end, any protruding scaffold

member in the line of operation should be cut off.

Note: The safe working load specified by the manufacturer may not be achieved due to the

unsuitability of many scaffolds to which these cranes are attached. In order to positively

determine their capacity in any given situation, it is strongly recommended that they are

tested in situ so that any deficiency in the scaffold may be rectified. Alternatively, the crane

may be derated.

19.4 SAFETY PRECAUTIONS BEFORE ERECTION

19.4.1 crane siting and foundation

The positioning of a crane often requires

to be very precise. It is a requirement that

there is a minimum clearance of 600mm

between slewing parts of the crane and

any fixed installations to prevent men

from being trapped. If this is not

practicable, access at these points must

be blocked off. (see Fig.10)

Fig.10 - showing the requirement to have a 600 mm clearance required between slewing part of crane and fixed installation

600

mm

Fig.9 - Typical type of small scaffold crane securely fixed with double couplers to scaffolding structure.



PART TWO



The Correct preparation of the crane foundation

is vital. The ground over which a crane has to

travel or operate should be carefully chosen or

prepared. There is often failure to realise that

ground conditions may not be capable of

supporting the required total load. Underground

hazards arise from cellars and basements (filled

or not), recently filled excavations, tidal or

floodwater areas where the ground water table is

high, buried pipes and mains etc.

It is imperative that the loading on any outrigger

jack is ascertained from the manufacturer or

supplier, therefore, the weight bearing

characteristics of the ground should be

thoroughly

examined and, if necessary, a good supply of

suitable timber or other material must he used to

spread the outrigger load.

On soft ground it will be necessary to pack solid material (timber, digger mats, hard core)

beneath crawlers and/or outriggers to allow for settling under load. Bearing plates or grillage

may be necessary to distribute the loads. (see Fig11)

For lorry mounted and mobile cranes, if there is any doubt about the suitability of the ground,

the following procedure must he adopted:

• test by lifting the load approximately 150mm off the ground and holding for a period over

one outrigger at maximum possible safe radius to see if the outrigger sinks.

• if an outrigger sinks, lower the load, increase the area of packing under the outrigger and

re-test as above.

19.4.2 work area control

Access to the working area during the lifting and moving operation should be restricted to

those involved in the work at hand.

The work area should be delineated and, where appropriate, process plant etc. which may

create risk should be isolated, also road closure may be necessary.

Care should he taken to ensure that, prior to erection of any large crane, air traffic control

authorities, both civil and military are consulted

Fig.11 - Showing Timber mats positioned due to soft ground



PART TWO



19.4.3 erection and dismantling

Insistence must be placed on the use of safety harness, and the wearing of safety helmets

should he enforced. It is essential that all personnel involved are totally familiar with, and

conform to the correct procedures specified by the crane manufacturer.

There must be available all the necessary parts and equipment to enable work to be carried

out safely. Substitution of parts with those of inferior quality or even incorrect components,

can lead to structural failure, often with disastrous consequences.

erection staff should:

• be supervised by a competent person,

• be familiar with crane erection and dismantling techniques.

• have access to the manufacturer’s instruction book appropriate to the particular crane.

Special care should be taken when unfolding swing-around fly jibs or lattice extensions.

Always ensure pins are in position before releasing the latch mechanisms. Careful control

during the swing around operation is important. Manufacturer’s instructions should be

followed, particular note being taken of the use of control ropes.

19.4.4 fly jibs

This is an additional jib which may be fitted to the end of the main boom of many cranes.

Care must be taken to ensure that the load/radius indicators and automatic safe load

indicators are compatible with this extension. It should be noted that the weight of the main

hook block should be deducted from the safe working load of the crane when using the fly

jib. The hooks on the main and fly jib must not he used simultaneously.

19.4.5 ropes

It is essential that the correct number

of hoist-rope falls are reeved for a

given duty in accordance with the

crane.

The ends of hoist and other ropes should be

properly secured. Where pear wedges are

fitted, they must be of the correct size and

the tail of the rope should extend sufficiently

through the wedge for it to be folded back on

itself and secured with a bulldog grip. (see

Fig.12)

Fig.12 - Tail rope folded back on itself and secured with a bulldog grip. Note: “U” part of bulldog clip should always be attached to the dead end of rope.



PART TWO



Where the rope cannot be looped

back on itself because of the rope

diameter, then a small length of the

rope can be attached to the dead end.

(see Fig.13)

The following points should also be

observed:

• when transferring wire rope from reel to drum, every precaution should be taken to avoid

twists and kinks.

• when reeving hook blocks on cranes capable of height extension, special care should he

taken to provide sufficient length of hoist rope to accommodate the height in use at the

time, and still leave the statutory two full turns on the drum when the hook is in its lowest

working position. In addition, the rope must be secured to the drum.

• ropes should lay correctly on all winding drums. Uneven winding causes gaps in the

layers, which produce undue wear and tear.

• wherever ropes need to be renewed or replaced, the replacement must be of correct size

and construction.

19.4.6 power supply

It is essential that the electrical power supply is of the correct voltage and phase and

adequate for the requirements of the crane. Electrical services necessary during erection

procedures should be connected by a qualified electrician.

Earthing electrodes, capable of dealing with all contingencies, including electric storms,

should be provided for tower and derrick cranes; where cranes are rail mounted, it will be

sufficient to earth the track.

Operational controls on the crane not required for use during the actual erection procedure,

should be isolated where possible.

19.4.7 overhead electric lines & cables

It is the responsibility of site management to ensure that all personnel on site are familiar

with the location of overhead and underground cables. For specific precautions see section

22. –Overhead and Underground Services

Should a crane contact overhead power cables, the operator should:

• remain inside his cab.

• warn all other personnel to keep away from the crane and not to touch any part of it or

the load.

• try, unaided to travel the machine to a safe position.

Fig.13 - Small length of rope attached to dead end and secured by a Bulldog Clip.



PART TWO



• if the machine is not mobile, remain in the cab until ADWEA Officials can make the area

safe.

• if, due to fire, or any other reasons the crane must be vacated by the operator, he should

jump clear as far from the crane structure as he is able, avoiding touching both crane and

ground simultaneously.

19.5 LOAD RADIUS INDICATORS

There is a specific requirement

that all cranes should have a load

radius indicator, clearly visible to

the driver, which will show the

operating radius and the

corresponding safe working load.

Load radius indicators may be

incorporated into safe load

indicators of the type which display

the safe working load.

Note:

On truck mounted cranes controlled from the truck cab, there will be an indicator on both

sides of the jib. (see Fig.14)

On derricking lattice jib cranes; an indicator comprising a pivoted weight to which a

pointer is fixed is secured to the side of the jib, and a load/radius scale moves relative to the

pointer as the elevation of the jib is altered.

On Tower Cranes; the indicator may be sited in the form of a scale which is activated by a

rope fixed to the jib or to the saddle of a fixed jib crane.

automatic safe load indicators

Where the term SWL is used in the following paragraphs, this refers to the maximum safe

working load of the crane as sited. The automatic safe load indicator (ASLI) is a safety

device provided to warn when the crane is being overloaded and at risk of overturning.

All cranes over one ton capacity are required to have such a device fitted and in proper

working order. They must be inspected each week and a record kept. The indicators are

required to give visual warning to the crane driver of an approach to SWL, and an audible

warning to those in the vicinity of the crane of an overload state. The percentage of SWL or

overload at which these devices operate will vary according to setting and requirements but,

correctly set, the driver receives his visual warning at between 90% and 97.5% SWL and the

site receives audible warning at 102.5% to 110% SWL., therefore, when the bell or hooter is

heard, the crane is overloaded and at risk.

Some types of ASLI incorporate a cut-out which prevents further movement of the load to

danger, after the audible warning has been given.

Fig. 9

Fig.14 - Showing Safe Load Indicator fixed to side of Telescopic Mobile Crane.



PART TWO



19.6 GENERAL OPERATING PRECAUTIONS

19.6.1 considerations prior to lifting

Before commencing work at the start of a shift, or when using a crane for the first time, the

crane driver should be satisfied that the test and thorough examination certificates are

current, and that the weekly inspection register is up to date. He must further ensure that the

cab’s uncluttered with material, visibility is not impaired by dirty windows and that all

controls, safe load indicators and load radius indicators function correctly.

Any defects must be reported in accordance with the company procedures. For a lift that

may require a long period of time to complete, continuous working may be essential and

therefore relief supervisors, crane operators and key personnel should be available and the

following strictly observed.

• no one involved in lifting operations should have taken alcohol.

• written procedure should be available to all involved in a major or special lift.

• the method and procedures for slinging should be to recognised standards.

• any signalling or communication system should be well practiced. (If radios are used,

they should have been previously checked and back up sets should be available).

• manufacturers’ “out of service conditions” must be known and adhered to.

19.6.2 load handling

Loads should only be moved when the

signaller can see both the load and

communicate with the driver. An additional

signaller must be provided if the load goes

out of sight.

Loads should not be lifted until directed by

the signaller/slinger to avoid fingers being

trapped between the load and the sling. The

load should then be lifted a short way to

enable an assessment to be made that the

load is properly slung. When satisfied that

this is the case, shutters, etc. should, where

necessary, be provided with tail ropes in

windy conditions. (see Fig.15)

• crane must not be operated in winds of a speed greater than those specified.

• loads must be carefully handled to avoid snatching, and slewed and travelled so as to

remain suspended vertically. They must not be pulled or dragged and must not be carried

over any person’s head.

Fig.15 - showing:-

• Load slung correctly with angle of slings at 900.

• Tail ropes used to stabalise load

• All personnel wearing the appropriate PPE,

and banksman wearing high visibility jacket.

Fig.7 Fig. 7



PART TWO



• care should be taken to allow for the increase in radius when the load is first raised. This

can arise from flexing of the jib, stretching of ropes and compression of hydraulics. It is

particularly important that persons do not stand between the load and any fixed object.

• cranes must never be overloaded and drivers must react immediately to the warnings of

the safe load indicator by either lowering the load, or by reducing the radius of operation.

Loads must never be left suspended from the crane hook when the crane is

unattended.

19.7 INSPECTION, EXAMINATION & TESTING

19.7.1 daily inspection

The manufacturer’s manual supplied with the crane normally provides details of the regular

inspection requirements and must be strictly followed. A visual inspection of the entire

machine and any tracks, etc., should be made before the crane is put to work.

The crane should be put through all motions by the driver and any defects reported

immediately. All brakes and clutches should be checked for correct operation.

19.7.2 weekly inspection

A competent person must be appointed to carry out a weekly inspection which should be

recorded on the company's format. This inspection should include the crane structure, and

mechanical components together with any structural ties, track etc. and the correct

functioning of the safe load indicator.

19.7.3 twelve monthly thorough examination

In accordance with Ministerial Order No. (32) Article (20), a thorough examination of the

machine must be carried by a qualified technician approved by the Ministry of Labour, and a

Test Certicate issued indicating full results of the thorough inspection.

19.7.4 maintenance inspections

Apart from the statutory requirements of inspection, testing and thorough examination, a

regular system of maintenance inspection and repair should be instituted in accordance with

the manufacturer’s instructions.

Before any repairs. adjustments or inspections are carried out, a proper system of granting

permission to work, including isolation of the machine should be properly implemented.

In addition to normal mechanical maintenance, the following points are worth regular

attention:

• an independent inspection should be carried out to ensure that no slowly developing fault

has become accepted, and that no-unauthorised modifications have been carried out and

that safety devices have not been tampered with by an operator for his own convenience.



PART TWO



• contractors name boards and similar wind resisting items should not be fitted without

reference to the manufacturer’s instructions.

• bolted joints should he inspected for tightness; suspect parts should he replaced to guard

against failure.

• where only part of the working rope is in regular use, the unused length should be run off

the drum at regular intervals to see that it remains undamaged.

• rail tracks, particularly curved sections, should be checked for level, soundness of

construction and maintenance of correct gauge.

• always ensure that the rope is the correct length for the crane as rigged. A minimum of

two full turns must be remaining on any winch, as the rope termination is not designed to

take line pull directly as reverse winding could occur.

• all ropes should be regularly lubricated according to manufacturers’ instructions.

• where ropes are running over plastic sheaves, it is possible that fatigue fractures of

internal wires may be present even though external wear is slight. Additional tests, other

than visual examination of the outer wires, may be necessary on these ropes.

Note: When a crane has been erected in a corrosive atmosphere e.g. sea air, near chemical

works etc., rope anchorages should receive special attention and may need to be cut

off and re-made periodically, to guard against the effects of hidden corrosion.

19.8 HOISTS

Hoists can be categorised as follows:

Goods hoists — used for lifting goods only and must not be used for transporting

passengers.

Passenger hoists — suitable for lifting persons and goods.

19.8.1 erection

• passenger and/or goods hoists should, as a minimum, be provided on any building

project which has four or more storeys and be extended, as the building progresses, to

the topmost floor.

• hoists should only be operated by fully trained and qualified personnel, be thoroughly

examined by a competent person after erection and before being put into service to

ensure that they have been properly erected and are safe to operate.

• the erection, extension and dismantling of hoists is a specialised job and should only be

carried out by competent erectors under the charge of a competent supervisor who will

have planned the work in detail, examined the site and assessed the correct method of

tying-in before work commences. If scaffolders carry out this work they must be suitably

trained and experienced.



PART TWO



19.8.2 base

A good base is essential. The hoist winch and other devices must be correctly positioned

and anchored to the base to ensure stability and to enable the load on the tower to be

carried. The base units of some passenger carrying hoists weigh several tonnes and

adequate lifting facilities should be available for installation purposes.

19.8.3 ties

It is essential that the freestanding height of the hoist mast is never exceeded, and that it is

tied to the building strictly in accordance with manufacturer’s instructions.

It is essential that, when tied to a building or scaffold (which itself must be adequately tied to

the structure), the mast is maintained vertical, so that no undue stress becomes imposed on

the tower; with consequent misalignment and interference with the platform.

19.8.4 enclosures and gates

• enclosures and gates must have a minimum height of 2m except when, by virtue of their

position, a lesser height is adequate to secure safety of all personnel. In no case may

the height of gates or fencing be less than 910mm.

• gates must be fitted at all levels where access is required. All gates must be closed

except for loading and unloading. It is good practice to display a notice “Keep Gates

Closed”. It is recommended that gates are interlocked; this is a requirement for

passenger hoists.

• landing gates generally protect only the entrance itself, often leaving access around the

gates where a person may reach in for some purpose and be struck by the cage or

platform. It is necessary to provide fencing to prevent this.

• open platform hoists that do not have a protective fence or cage around the platform

must have the hoistway completely enclosed with suitable steel or wire mesh throughout

their height so that, should any part of the load become accidentally dislodged from the

hoist platform, it is contained with the enclosed tower.

19.8.5 platforms

• hoist platforms should be sound and maintained in good condition. Broken or missing

boards can easily cause a load to tip, or a man to fall when loading.

• gaps between the platform or cage and the landing, and between an open platform and

the hoistway, must be sufficiently small to prevent persons falling down the hoistway

when loading or unloading.

• platform must carry a notice stating the safe working load. On a goods hoist a notice

prohibiting passengers must also be displayed.



PART TWO



19.8.6 goods hoist

safety devices (see Fig.16)

• an over-run device must be fitted just above the highest platform position required, or

near the top of the mast.

• on all types of hoist, the top over-run device must be correctly set in accordance with the

manufacturer’s instructions, to ensure that there is no danger of headgear being struck by

platform or cage.

• bottom over-run devices must also, where fitted, be properly set. In the case of rack and

pinion hoists, there may be a danger of the platform or cage climbing off the top of the

mast, particularly during erection and dismantling.

• hoists must be fitted with an arrestor device to support the platform or cage, fully loaded,

in the event of failure of the hoist rope or driving gear.

4

2

4

4

3

2

2

1

7

5

6

8

Fig. 16. - Showing sketch of a cantilever Goods Hoist . (Wire mesh surround to the hoistway has been ommitted allowing detail to be shown).

No’s. Denote:-

1. Over run device

2. 2m high landing

gate

3. Hoist enclosure

4. Hoist mast tied

into building.

5. Hoist arrestor

device.

6. Hoist operated

from one

position only

giving operator

unobstructed

view.

7. Dead man

handle.

8. S.W.L. marked

on hoist

platform.



PART TWO



19.8.7 passenger hoists

safety devices (see Fig.17)

All passenger hoists may be used to carry goods up to the rated SWL. The usual procedure

is for the driver to travel with the goods, and his weight, calculated as a fraction of the

permitted number of persons, should be deducted from the payload (e.g. SWL 1 tonne or 12

men; therefore 1 man = 1/12 tonne; therefore payload = 11/1 2 tonne). When passengers

are carried, the driver is included in the permitted number of passengers.

Enclosures must be at least 2m high at the base and at landing stages, and should be of a

mesh size as laid down in BS 4465.

The gates must be fitted with mechanical or electrical locking devices, so that the gates

cannot be opened except when the cage is at the landing stage and so that the hoist cannot

be operated unless that gate is closed and the lock is in the shut position. ( Where this is

not practicable, it is allowable for the gate to be locked from inside the landing platform

provided the hoist operator is the only one issued with the key).

Cage gates must be mechanically and/or electrically interlocked. Access and egress gates

at working platform level must also be interlocked.

4

9

2

4

9

9

4

1

1

8

6

7

10

5

9

2

3

No’s Denote:-

1. Over run

device

2. 2m high

landing gate

3. Hoist

enclosure

4. Hoist mast tied

into building.

5. Hoist arrestor

device.

6. Hoist operated from

one position.

7. Dead man handle.

8. Cage interlock on Gates.

9. Landing gates interlock.

10.S.W.L. on

hoist.

Fig. 17 Showing sketch of a Passenger Hoist with

all the safety devices fitted.



PART TWO



Hoists may only be operated from one position. This normally is from inside the cage. If, for

any reason, the cage stops between landing stages, it should be isolated electrically from

outside to prevent any possibilily of further movement. There is a mechanical device that

keeps the gates locked in such circumstances.

Passengers should remain in the cage until a competent person instructs them on the

correct method of egress, which may be through a roof trapdoor which is kept locked, except

when properly needed. A notice bearing instruction to this effect, or with any variations

peculiar to that specific model of hoist, should be prominently displayed in the cage

The SWL figure and the permitted number of passengers must be marked on the cage.

Drivers have particular responsibility to see that the hoist does not become overloaded.

The distance from the underside of the cage, when at its lowest position, to the ground, is

carefully calculated by the makers to prevent damage to the cage and its occupants if the

cage over-runs the bottom landing level. It is essential that the ground space beneath the

cage is kept completely clear in case such emergency arises, despite any trip mechanisms

incorporated by the manufacturer.

The operation of mechanical safety gear from inside the cage should be expressly forbidden

except in an emergency. For checking purposes, the safety gear should occasionally be

fired with the manual lever, if fitted, to ensure that it is working properly.

19.8.8 beam hoists

Hoists must be erected in accordance with manufacturer’s instructions and, if secured to

scaffolding or other temporary support, the structure must be designed accordingly. Normal

safety procedures apply in the operation of beam hoists, but the following are particularly

relevant: (see Fig.18)


• barriers must be erected and maintained at the loading area to prevent unauthorised

access.

• the load should be in full view of the driver throughout its travel.

• care must be taken to ensure that the

load does not snag or become dislodged

during lifting.

• regular checks should be made on the

security of the winch and its frame.

• the safety and security of the electrical

supply and controls must be checked,

and manufacturer’s maintenance

instructions must be followed.

Fig.18 - Showing type of Beam Hoist



PART TWO



19.8.9 control systems

• with passenger hoists, the controls are inside the cage. In the case of goods hoists, the

controls are outside the cage or platform and it is essential that the driver is positioned so

that he can see the hoist over its entire run. Where this is not possible, a suitable

signaling system must be introduced.

• marking of the hoist rope in different colours for each landing can also be of assistance.

• hoist operating rope, lever or other controls should be so situated that the hoist can be

operated from only one position.

19.8.10 operation (general)

• operatives should have a clear view and be trained to place barrow handles facing the

offloading exit when loading on the ground, so that any walking on the raised platform at

delivery point is reduced to a minimum, and should also be instructed to close all gates

after use.

• all loads on the platform must be secure and there should be no projections.

• on passenger hoists such loads should be contained within the cage and not leaned

against the cage gates or doors. No attempt should be made to use a passenger

hoist with the cage roof trapdoor left open to permit the protrusion of long loads

(the trapdoor should in any case be interlocked).

• manufacturers may be able to supply a vertical extension to the cage to accommodate

longer loads. The SWL of a hoist is based upon an evenly distributed load. Where

vertical loads are carried there may be a need to derate the SWL of the hoist due to

imposed loads.

19.8.11 wind speeds

On all exposed sites and at heights, hoists can be subjected to wind forces much more

severe than at ground level. Most manufacturers quote wind speed limits at which their

machines will operate safely. These limits ought never to be exceeded.

In wind conditions in excess of the recommended limit, the hoist platform should be lowered

to the ground and the mains supply isolated.

19.8.12 maintenance

Systematic maintenance should be carried out at the manufacturer’s recommended intervals

by persons competent for the purpose.

Regular maintenance of both electrical and mechanical systems, should be carried out by

competent electricians and mechanics, to keep hoists in goad working order.

Hoist electrical work should only be carried out by an electrician trained in the control

systems involved. Drivers should not be permitted to attempt electrical maintenance, but

they can help to avoid breakdowns by observing chafing in the supply cables, or unusual

noise or performance.

rack and pinion hoists

The lubrication of the rack is a job normally carried out by the driver during maintenance but,

in order to have safe access, he must have assistance with the operation of the hoist. The

manufacturer’s recommendations should be followed regarding correct lubricant and



PART TWO



method.



PART TWO



swivel hoists

There are additional dangers with the operation of this type of hoist, because the cage must

be swung towards the landing levels for loading/unloading. Either:

• someone may try to open the gate(s) and lean into the hoistway to swing the cage into

position; or

• the cage may swing away from the landing level if it has not been locked into position.

These problems can be overcame by fitting hoist gates split into upper and lower gates and

by checking to make sure that the cage is locked into position at that level, before opening

the lower gate.

A single gate at least 910mm high may be fitted instead of the larger split gate, providing that

no-one can be struck by any moving part of the hoist or falling materials should they lean

into the hoistway.

winch operated hoists

All ties should be kept clear of the hoist rope and power cables and, as far as possible, out

of the way of all building operations, so that there is no temptation for anyone to remove

them. Proper planning can remove the risk of occurrences such as this, and other forms of

dangerous interference. Such planning must be backed by adequate site discipline and

enforcement of all instructions so that alterations may be made only by authorised

personnel.

19.9 APPROVED CRANE SIGNALLING SYSTEM

Operation Start

(Follow my Instructions) Stop Emergency

Stop

Clench and

Unclench Fingers to

signal winch

the load Hoist Lower

Lower

Slowly Slew In Direction

Indicated

Jib Up

Jib Down

Derricking Jib Signal with one Hand -Other on Head

Travel to Me Travel From Me

Extend Jib

Retract Jib Travel in Direction Indicated OPERATION CEASE (Or cease to follow my instructions)

NOTE: Signaller should stand in a secure position where he can see the load and can be clearly seen by

the Crane Driver. If at all possible he should face the driver. Each Signal should be precise.

SAFETY CHECKLIST - MOBILE & TOWER CRANES


ADM/H&S/CL/2.19/1 01 March 2005 SAFETY CHECKLIST - MOBILE & TOWER CRANES 1 of 2

MOBILE CRANE OPERATIONS

SAFETY CHECKLIST FOR PRODUCING METHOD STATEMENTS

Method statements for mobile crane operations should normally include the following so far as

is relevant in the circumstances

�� Name and address of the site to which the method statement relates.

�� Indication of whether the operation will be undertaken as a “contract lift” or as a “crane hire”.

�� Name and address of the contract lift/crane hire company.

�� Name and address of the company arranging for the contract lift/hiring the crane.

�� Date and duration of operation.

�� Time of crane arrival on site and of first lift.

�� Details of the crane(s) concerned and copies of relevant certification.

�� Name of the person appointed to have overall control of the lifting operation.

�� Name of the appointed safety adviser and arrangements for monitoring the work.

�� Confirmation of training standards for crane driver and slinger/signaller and methods of

communication.

TOWER CRANE ERECTION/DISMANTLING

SAFETY CHECKLIST FOR PRODUCING METHOD STATEMENTS

Method statements for tower crane erection/dismantling operations should normally include

the following so far as is relevant in the circumstances

�� Name and address of the company carrying out erection/dismantling.


�� Names of the supervisor / foreman and appointed safety adviser and arrangements for

monitoring the work.

�� Details of the tower crane.

�� Date and time of commencement of the operations.

�� Details of the mobile crane to be used (see mobile crane method statement checklist) including

copies of relevant certification.

�� The sequence of erection / dismantling.

�� Details of limiting wind speed and method of checking wind speed.

�� Details of where the crane is to be sited.

SAFETY CHECKLIST - MOBILE & TOWER CRANES


ADM/H&S/CL/2.19/1 01 March 2005 SAFETY CHECKLIST - MOBILE & TOWER CRANES 2 of 2

�� Details of the items to be lifted including weights and dimensions.

�� Height(s) of lift(s).

�� Details of lifting gear to be used.

�� Adequacy of outriggers load spreading pads.

�� Means of checking wind speed.

�� Provision of warning notices, barriers, cones etc.

�� Arrangements for notification to police and highways authority where necessary e.g. for

temporary road closure.

�� Provision of parking area for lorries unloading.

�� Provision of temporary lighting if required.

Note

This checklist is intended to aid the production and approval of method statements. It is not an

exhaustive list of every possible issue that may need to be addressed for any given task.

The safety precautions to be followed during erection/dismantling including :-

— Confirmation that members of the erection/dismantling team will wear full safety harness at all

times whilst aloft.

— Confirmation that harnesses will be secured as necessary e.g. when bolting up, sledging,

slinging, etc.

— Details of proximity hazards and appropriate precautions.

— Details of road closures, police notifications, etc.

— Details of how the crane testing will be carried out. (in accordance with BS71 21: Part 2 1991)

SECTION 20

SECTION 20

LIFTING GEAR

INTRODUCTION 1

DEFINITION


20.1 QUALITY OF LIFTING GEAR 2

20.2 SLINGING CONFIGURATION 2

20.3 SLING ATTACHMENTS 3

20.4 STRESSES ON SLINGS AT VARYING ANGLES 3

20.5 TYPES OF LIFTING GEAR 4

20.6 SLING SELECTION 8

20.7 BASIC PRECAUTIONS 8



PART TWO


ADM/H&S/Pt 2 01 March 2005 LIFTING GEAR 1 of 9

SECTION 20

LIFTING GEAR

INTRODUCTION

Lifting must, by its very nature, be regarded as a hazardous operation. The severe usage to which

lifting gear is often subjected, together with the serious consequences to life and property which may

result from any failure, make it important that maximum attention is paid to the correct use and

maintenance of such gear. This can best be achieved by :-

• good design and workmanship.

• careful testing and inspection after manufacture and repair.

• detailed planning and correct and careful use of the gear.

• regular, careful inspection and maintenance during the life of the gear.

It is unfortunate that, whereas considerable importance is generally attached to the selection and

training of crane drivers, comparatively little attention is paid to banks men / slingers who are an

equally important part of any lifting operation. Management should accept that the duty of banks men /

slingers is not one that can be undertaken by untrained persons.

DEFINITION

Any loose equipment used for lifting with a lifting appliance, e.g. rope or chain slings, webbing slings,

hooks, eyes, shackles, eyebolts etc. (does not apply to ropes used for haulage on the level or

lashings).

MAIN APPLICABLE LEGISLATION




PART TWO



20.1 QUALITY OF LIFTING GEAR

It is of the utmost importance to ensure that any lifting gear put to use is of the correct

quality. To that end the equipment must be manufactured in accordance with relevant British

or internationally recognised standards, and where applicable, have current records of test

and examination.

20.2 SLING CONFIGURATIONS

Sling configurations shown in Fig. 1 below are some of the most common sling

configurations in use in the construction Industry:

Fig.1

1 Single Leg Sling - normally used on loads with a single point of attachment with the sling in a vertical plane.

2 Two Legged Sling - Used when two lifting points are required. The angle between the legs of the sling should not exceed 90o

3 Three Legged Sling - This type of sling not to be used when the angle between any leg and a line vertically below centre master ring exceeds 450

4 Four Legged Sling - Angle between legs on a four legged sling is measured between diagonally opposite legs and should not exceed 45o

(1) (2) (3) (4)



PART TWO



20.3 SLING ATTACHMENTS

Attachments of a sling to a load will normally fall into four categories as shown in Fig. 2

below:

20.4 STRESSES ON SLINGS AT VARYING ANGLES

Chart No.1 –

Shows the

different stresses

that are imposed

on slings, chains,

ropes etc. when

included angles

are increased. e.g.

at an included

angle of 1200

stresses on sling

lifting 1 Ton is

exactly 1 Ton.

At 1710 – stresses

on a sling lifting a

1 Ton Load is

nearly 6 Tons.

Fig. 2

1. Two single leg slings used in a Basket Hitch. NOTE: Total load that may be lifted – provided that no

included angle exceeds 900 – is 2.1x that marked on the sling.

2. Choke Hitch Double Wrapped. NOTE: Total load that may be lifted is that marked on the sling.

3. Basket Hitch.

NOTE 1: Total load that may be lifted when the included angle does nor exceed 900 is 1.4 x that marked

on the sling.

NOTE 2: A Basket Hitch should only be used when the sling is passed through part of the load – and

the load is balanced on the sling.

4. Simple Choke Hitch. NOTE: Total load that may be lifted is that marked on the sling.

Chart No. 1

(1) (2) (3) (4)



PART TWO



20.5 TYPES OF LIFTING GEAR

20.5.1 alloy steel chains

• welded alloy steel chain slings shall have permanently affixed identification stating size,

grade, rated capacity end sling manufacturer.

• hooks, rings, welded or mechanical coupling links and other attachments when used

with alloy steel chains shall have a rated capacity at least equal to that of chain.

• job or shop hooks and links or make shift fasteners, formed from bolts, rods etc. or other

such attachments, shall not be used.

• rated capacity (working load limit) for alloy steel chain slings (single/multileg) shall not

exceed the values given by the manufacturer.

• whenever wear at any point of any chain link exceeds 10 per cent reduction in diameter,

the chain shall not be used,

20.5.2 wire rope slings

• the safe working load recommended by the manufacturer for

various sizes and classifications of wire ropes shall be

followed.

• wire ropes shall not be secured by knots.

• each wire rope used in hoisting, lowering or in pulling loads

shall consist of one continuous piece without knot or splice.

• wire rope shall not be used if in any length of ten diameters, the total number of visible

broken wires exceeds 5 per cent of total number of wires, or if the rope shows other signs

of excessive wear, corrosion or defect. (see Fig. 3)

“soft eyes” type

Formed in this manner, are often used for convenience,

but in use they become flattened around the eye and suffer

considerable wear through friction. They should therefore

be frequently inspected and, at the first sign of damage,

removed.

By far the better method is for the eye to be formed by

bending the rope around a thimble which takes the rub

whilst the sling is in use and which prevents the rope itself

being damaged.

Having formed the eye, fixing back the free end is achieved

by using a ferrule or socket.

(see Fig.4)

Fig.4 - Showing Ferrule Eyes

Fig. 9

Fig. 3 - showing broken strands in wire rope



PART TWO



20.5.3 natural rope and synthetic fibre

• all splices in rope slings shall be made in accordance with manufacturer’s recommen-

dation,

• spliced fibre rope slings shall not be used unless they have been spliced as per the

manufacturer’s recommendation,

• knots shall not be used in lieu of splices.

• natural and synthetic fibre rope slings shall be immediately removed from service if any of

the following conditions are present:-

� distortion of hardware in the sling.

� abnornal wear.

� powdered fibre between strands.

� broken or cut fibres.

� variations in the size or roundness of

strands.

� discolouration or rotting.

20.5.4 synthetic webbing slings

Synthetic webbing shall be of uniform thickness and width. Fitting shall be of a minimum

breaking strength equal to that of the sling; and free of all sharp edges that could in any way

damage the webbing.

types of webbing Slings: (see Fig.5)

1. Endless Type Webbing Sling

2. Cargo Type webbing Sling

3. Round Type Webbing Sling

Fig.5 - Showing various types of webbing slings



PART TWO



attachment of end fittings to webbing and formation of eyes

Stitching shall be the only method used to attach end fittings to webbing and to form eyes.

The thread shall be in an eyes pattern and contain a sufficient number of stitches to develop

the full breaking strength of the sling.

environmental conditions

When synthetic web slings are used the following precautions shall be taken:

• nylon web slings shall not be used where fumes, vapours, sprays, mists or liquid of

acids or phenolics are present.

• polyester and polypropylene web slings shall not be used where fumes, vapours, sprays,

mists or liquids of caustics are present.

removal from service

synthetic web slings shall be immediately removed from service if any of the following

conditions are present:-

• acid or caustic burns

• melting or charring of any part of the sling surfaces

snags, punctures, ~ tears or cuts

• broken or worn stitches

• distortion of fittings.

Table 1. above shows the working load limit when using 1 webbing sling - Double ply at varying angles and sling configuration.



PART TWO



20.5.5 hooks

Every hook used for raising or lowering or as

means of suspension shall either:

• be of such shape as to reduce, as far as

possible. the risk of such displacement.

(see Fig.6) for types of hooks normally

used on building construction work.

or;

• be provided with an efficient device to

prevent the displacement of the sling or

load from the hook (see Fig 7)

20.5.6 spreader beams

Spreader beams are used to support long or wide

loads during lifts and may be used when headroom

is limited.

They eliminate the hazard of load tipping and those

arising from the use of wide sling angles.

Alternatively they are used when the load will not

sustain the comprehensive force applied by slings

used at angles in excess of 1200. (see Fig.8)

20.5.7 eyebolts

Fig. 6 - “C” Type Hook – sometimes referred to as the “Liverpool “C” Hook

Fig. 7 - Eye Hook with Safety Catch

Fig. 8 -Showing Selection of Spreader Beams

Fig. 9

1. Dynamo Eye Bolt. Designed for vertical lifting only

2. Collar Eyebolt. Has a small eye with a large collar. Can be used for angular loads in the plane of the eye, but this will reduce the SWL.

3. Collar Eye Bolt with Link. This type takes a higher angular loading than all the others and allows the pull to be taken in any direction.

Eyebolts are made to screw into or

through a load and when installed,

the following are the main points to

consider: (see Fig.9)

• collar must be at right angles to

the hole

• have full contact with the surface

and properly tightened

• where hooks will not freely locate

into the eye or link of the eyebolt,

shackle must be used

• ensure that metric threads

threaded eyebolts are not

inserted into imperial thread

holes.

(1) (2) (3)



PART TWO



20.6 SLING SELECTION

The different types of slings used in the construction industry can be put to use in many

different ways. It is therefore imperative that that slings of the correct type, SWL and length

are selected for use in any particular lifting operation. Each lift should be assessed with due

consideration of the following:-

20.6.1 weight of load to be lifted

The weight of routine pipes, timber, steel etc. can often be established from the

manufacturer or supplier, from delivery tickets or by calculations. Where weights of loads

cannot be determined e.g. pile extraction, they must be estimated by a person of experience

in such matters.

20.6.2 load dimension

The size and shape of the load must be considered together with any lifting points which

may be available. An assessment of the centre of gravity must also be made to ensure the

crane hook is placed above that point.

20.6.3 positioning of the load

Many loads may have to be placed at an angle or have one face resting directly on a surface

which would prohibit removal of the slings if the more traditional “wrap around” method was

used.

20.6.4 headroom

If lifts are to take place in areas of restricted headroom, then spreader beams may be more

appropriate than other types of slinging methods.

20.6.5 method of detachment

It is not uncommon in building and civil engineering, particularly when slinging structural

steel members, that access to the load when it has been lifted into position is extremely

hazardous. Consideration therefore should be given to the use of quick release shackles etc.

20.7 BASIC PRECAUTIONS

20.7.1 lifting gear

• has been tested and examined by a competent person and obtained a certificate signed

by the person specifying the safe working load.

• is of good construction, sound material, adequate strength, suitable quality and free from

patent defects.

• is inspected prior to use on each shift and as necessary during its use to ensure that it is

safe. Defective equipment shall be removed from service.



PART TWO



• it is clearly marked with its safe working load and identification number.

• all unused legs of the sling are hooked back to the eye to prevent the hook swinging

where it may strike personnel or get caught up.

• It is free from makeshift devices. i.e. must not be shortened with knots or bolts.

20.7.2 hooks

• are of sufficient size to permit the load to be taken on the bed and not the tip.

• is placed over the centre of gravity of the load to avoid the load swinging.

20.7.3 landing space

• suitability of the landing is established together with the quality of any chocks, battens

etc. on to which it is to be placed.

20.7.4 slinger

• ensures that the slings do not pass directly over sharp edges such that they may be

damaged.

• always wear a safety helmet, safety boots and gloves, and wear high visibility clothing so

that they are easily identifiable.

• give clear signals to the crane driver

20.7.5 load

• is checked to ensure that it is “free” and not trapped in any way and lifted slightly then

checked for stability and angle.

• is never directed over any persons head.

• Is within recommended safe working load of the equipment.

• securely attached to the appliance.

• adequate steps have been taken through the use of suitable packing or otherwise to

prevent the edges of the load from coming into contact with the lifting gear where it is

likely to result in damage.

• hands and fingers not be placed between the sling and its load while the sling is being

tightened around the load.

20.7.6 after use

It is removed from the immediate work area so as not to present a hazard to employees.

Note: Only Competent persons approved by Ministry of Labour and Social Affairs to test

lifting appliances are authorised to test and certify all types of lifting gear.

SECTION 21

SECTION 21

CONFINED SPACES

INTRODUCTION 1


21.1 PLANNING 2

21.2 SAFE SYSTEMS OF WORK 2

21.3 PERSONNEL SELECTION 2

21.4 TRAINING 3

21.5 TOXIC AND FLAMMABLE ATMOSPHERES 5

21.6 ATMOSPHERE MONITORING 5

21.7 PERMIT TO WORK 7

21.8 WORKING PRECAUTIONS 7

21.9 RESCUE 8

21.10 BREATHING APPARATUS 9

21.11 PERSONNEL 11

21.12 SEWERS 12

21.13 BACTERIAL INFECTION & HYGIENE 12

21.14 DETERIORATING ATMOSPHERE 13

21.15 SUBSTANCES WHICH MAY BE ENCOUNTERED 13

IN A CONFINED SPACE



PART TWO


ADM/H&S/Pt 2 01 March 2005 CONFINED SPACES 1 of 15

SECTION 21

CONFINED SPACES INTRODUCTION

For the purpose of safety the term ‘confined spaces” covers a great variety of workplaces which have

limited access and inadequate ventilation. They are therefore potentially dangerous places in which to

work because they may trap hazardous concentrations of toxic or flammable gases or vapours.

Confined spaces are also liable to become deficient in oxygen due to the build-up of a gas or vapour

which is not itself toxic but which displaces the breathable air.

Very often, the dangerous atmosphere is a result of the work being done for instance welding,

painting, flame cutting and the use of adhesives and solvents.

At some time or another almost any place on a construction site may become a confined space. Some

are quite obviously confined spaces e.g. tanks, ducts, bore-holes, silos, manholes, furnaces,

pipelines, sewers and underground chambers. But serious accidents have occurred in the past in

such places as rooms which were ultimately to become occupied rooms and which were therefore not

regarded as confined spaces when construction work was going on in them.

Everyday operations of the construction industry often involve work in excavations, holes and so on

which may not be recognised as confined spaces, but which nevertheless may present a danger of

toxic, flammable or oxygen-deficient atmospheres.

If there is any doubt whether or not a particular workplace presents the problems of a confined space,

atmospheric testing must be carried out to determine what are the hazards, if any.

If atmospheric problems are found to exist, first considerations should be:

• whether it is practicable to substitute safer materials than those which are producing the dangerous

atmosphere

• whether alternative methods of work could be adopted which would not give rise to hazards.


Ministerial Order No. (32) Year 1982 – Article. (5), (6), (9) & (13)



PART TWO



21.1 PLANNING

The special conditions of confined space working make it vital that the work should be

planned in detail and risk assessments made in order to determine appropriate health and

safety measures and emergency arrangements. (see Pt 2 section 19)- Risk Assessments -

Part One Manual

These measures should be incorporated in a safe system of work and included in the health

and safety plan which the principal contractor will have developed.

21.2 SAFE SYSTEMS OF WORK

definition

An agreed, set sequence of operations, using

guards, safety devices and protective equipment,

so as to complete a job safely and without danger

to health. They can be classified broadly into three

areas: (see Fig.1)

• simple systems covering safety equipment.

• formaI procedures for carrying out work

processes (e.g. entry into confined spaces).

• special applications (lock-off systems).

The following measures are priorities:

• test atmosphere prior to entry.

• continuous monitoring at the workplace.

• maintain contact between operative and attendant in free air who is trained to carry out

emergency procedures.

21.3 PERSONNEL SELECTION

Persons who will be expected to work in confined spaces must be physically and mentally

suitable. It is no job for the claustrophobic or the foolhardy. It is recommended that

employees taken on for such work are over 18 years and preferably under 55 years of age.

Heavy manual tasks, with the necessity for rescue training and the possible added burden of

working in breathing apparatus may make the job too demanding for older men. Men of 55

Fig.1 - Photo showing entry into a sewer manhole using winch, tripod, safety harness etc. and following the correct safe system of work

Fig.1



PART TWO



and over who are already employed on work in confined spaces should be medically

examined annually and additionally after any illness.

no one with any of the following disabilities should work in confined spaces:

• a history of fits, blackouts or fainting

attacks.

• a history of heart disease or heart

disorders.

• high blood pressure

• claustrophobia or other nervous or

mental disorder.

• back pain or joint trouble that would limit

mobility in a cramped space.

• deformity or disease of the lower limbs

limiting movement.

• asthma, bronchitis or shortness of

breath on exertion.

• deafness.

• meniêre’s disease or any illness causing

giddiness or loss of balance.

• chronic skin disease.

• serious defect in eyesight.

• lack of sense of smell.

21.4 TRAINING

Work in confined spaces must only be undertaken by employees who have been properly

trained for the job.

It is the employer’s duty to provide such information, instruction, training and supervision as

is necessary to ensure, so far as is reasonably practicable, the health and safety at work of

his employees.

Training must be planned specifically for:

• supervision

• persons who will be expected to enter

confined spaces to work in them

• persons who will act as attendants

• persons appointed to form a rescue team.

The precise form of the training and instruction must depend on the individual operations,

but in addition to any specialised training for particular tasks, general training for work in

confined spaces should include:

• observance of the safe system of work (permit-to-work).

• restrictions on size imposed by existing manholes or access shafts should be taken into

account when developing safe systems of work.

• training in the procedures for rescue, including the correct use and maintenance of

rescue equipment and resuscitation equipment.



PART TWO



instruction :-

• on the suitable types of breathing

apparatus and practice in their use, care

and maintenance.

• in first aid, treatment of shock, resuscita-

tion.

• practice in the correct procedures in

emergencies, especially evacuation.

• in the use of atmospheric testing

equipment.

• practice in the correct use of fire

fighting equipment.

• (where applicable) observance of

personal hygiene rules to avoid health

risks.

• (where available and applicable) the

use of mobile radio.

Note: Instruction in the use and maintenance of equipment can often be given by the

Manufacturer.

21.4.1 practice drills

Practice drills are an essential part of

training; theoretical knowledge is not enough

to ensure that the right action will be taken in

a real emergency. The use of breathing

apparatus especially should be practised

regularly, also the procedures for

emergency evacuation.

The drill should ensure that employees

acquire a sound working knowledge of the

signal communicating system to be used

between persons working in the confined

space and those in attendance outside.

They must also learn the correct procedure for summoning medical aid or the emergency

services and the use and maintenance of any recovery winches and/or other methods of

recovery.

It is important that employees should learn to recognise situations requiring the use of

respiratory protective equipment and be able identify the appropriate atmosphere testing

equipment.

Refresher courses should be given as necessary on a regular basis. It is important that a full

and up to date record should be kept of the type of training given to each individual. (see

Fig.2)

Fig.2

Fig.2 - Showing a Confined Space Team having a practice drill entering a 8m deep sludge collecting chamber.



PART TWO



21.5 TOXIC AND FLAMMABLE ATMOSPHERES

In the context of confined space work the term nontoxic can be dangerously misleading. In a

small unventilated space any of the whole range of gases and vapours found in industry in

sufficiently high concentration could create an atmosphere that is not safe to breathe.

Contaminants can arise from:-

• the space itself (e.g. leaded petrol tanks).

• earlier process (e.g. degreasing, in which case a residue of trichlorethylene solvent in the

tank could emit fumes when the sludge is cleaned off).

• previous contents where confined spaces such as tanks have previously contained

flammable, explosive or toxic materials and where the work being done could create

vapour from the remains of the previous contents.

21.5.1 adjoining plant

Gas or vapour may enter the confined space from adjoining plant if it has not been

effectively isolated. To prevent exhaust fumes from entering a confined space and causing a

hazard, vehicles should not he sited near the entrance.

21.5.2 nearby undertakings

Where any deep narrow excavation (e.g. bore-hole) is adjacent to spoil heaps, sewage

works, gas works, old drainage systems, chemical works or refineries there is a danger of

seepage into the confined space. Air testing must be carried out before entry, and thereafter

at intervals for oxygen deficiency and toxic or flammable gases.

An atmosphere which is not fit to breathe may exist at the bottom of a hole from stagnant

water or from the subsoil itself e.g. the passage of water through chalk for instance, can

release carbon dioxide.

21.6 ATMOSPHERE MONITORING

Wherever work is carried out in confined spaces,

adequate ventilation must be provided if there is any

risk of the air becoming deficient in oxygen or

contaminated with dangerous or injurious dust, fumes

or gases. It is also requirement that atmospheric

testing must be carried out if the air in any confined

space is suspected of being poisonous or

asphyxiating. (see Figs. 3 & 4 )

No person must be allowed to enter until a

competent person is satisfied that entry is safe.

3



PART TWO



An atmosphere which is safe on entry may become

unsafe through any of the reasons given above, and

continuous monitoring is therefore necessary while

persons are working inside.

The odour of gases is useful in giving an early

indication of possible danger, but it must not be relied

on without the back-up of atmosphere testing

instruments.

The sense of smell varies greatly from person to

person and is poor in the older age groups. Some

dangerous gases have no smell (for instance

carbon monoxide and methane) and others

paralyse the sense of smell (for example hydrogen

sulphide).

21.6.1 oxygen deficiency

Without any poisonous gas being present the atmosphere may become lethal through

depletion of oxygen. Normal air contains about 21% oxygen, 79% nitrogen. Below 17%

oxygen, a flame will not burn and the atmosphere is not fit to breathe.

The person working in an oxygen-deficient atmosphere may not be aware that he is in

danger. Consequently symptoms such as breathlessness, faintness, lack of physical co-

ordination, should lead to immediate evacuation, since unconsciousness can follow rapidly

and unexpectedly.

Several different situations can lead to an oxygen-deficient atmosphere:

21.6.2 rusting process

Where a steel vessel has been closed for some considerable time, the oxygen in the air may

have become absorbed onto the inner surface of the vessel through the rusting process. The

presence of moisture inside a steel vessel increases the likelihood of this occurring.

21.6.3 contaminated soil

Oxygen deficiency and concentrations of carbon dioxide may be encountered in tunnels or

deep excavations on land contaminated with coal waste or decaying organic matter, Slow

oxidation of buried coal waste and microbiological decay of organic matter takes up the

oxygen of the air in the surrounding soil leaving a nitrogen gas mixture deficient in oxygen

and rich in carbon dioxide. Falling atmospheric pressure would allow this gaseous mixture to

seep into tunnels or deep excavations in the contaminated ground.

21.6.4 decay of organic matter

Oxygen deficiency can result (for example in sewers or excavations in contaminated soil)

from the absorption or biochemical depletion of the available oxygen by organic matter.

Figs. 3 & 4 showing two types of portable gas monitors, both capable of detecting up to 4 different gasses e.g.

Low Oxygen Hydrogen Sulphide Methane Gas Carbon Monoxide

Fig.4

4



PART TWO



21.6.5 oxygen enrichment

The opposite condition, an oxygen-enriched atmosphere, can be equally dangerous. With an

excess of oxygen in the air some substances containing organic matter become liable to

spontaneous combustion. Grease and oil, for instance, may self-ignite, and also paint,

plastics, textiles, paper and wood.

Oxygen in more than its normal proportions in the air also greatly increases the

combustibility of all other materials. A fire in an oxygen-enriched atmosphere develops with

great speed and ferocity and may be particularly difficult to extinguish.

The atmosphere can accidentally become too rich in oxygen as a result of work which

releases extra oxygen into the air, for instance oxy-propane cutting.

Note: It is dangerous to purge with oxygen instead of air, and in no circumstances should

oxygen be introduced into a confined space to “sweeten” the air or to provide

ventilation. A leak of liquid oxygen or oxygen gas must be treated as a serious matter.

21.7 PERMIT TO WORK (see Pt 2 section 11) – Permit to Work.

21.8 WORKING PRECAUTIONS

Carrying out a job in a confined space often

entails working in cramped conditions, so work

shifts should be broken at intervals by rest

periods which the worker should spend in fresh

air. He must in any case leave the confined

space at the expiry of the time limit on the

permit-to-work.

“No smoking and no naked lights’’ must be

the rule in and near all confined space

operations. Only non-sparking tools must be

used, and no nylon lines or nylon clothing

allowed because of the danger of generating a

spark from static electricity.

All electrical tools and lighting must be of the flameproof or intrinsically safe type. The

British/American Approvals Service for Electrical Equipment in Flammable Atmospheres

defines ‘intrinsically safe’’ as ‘‘Systems comprising apparatus and interconnecting wiring in

which any spark or thermal effect in any part of the system for use in the hazardous area, is

incapable, under prescribed conditions, of causing ignition of a given gas or vapour.

Fig.5 - Showing Forced ventilation equipment used to provide clean air for workers cleaning an old sludge holding tank.



PART TWO



(BASEEFA Certification Standard SEA 3012). Intrinsically safe is also defined in BS 1259.

Cylinders containing compressed gases, or any lines or equipment connected to cylinders

outside the confined space, should be removed at meal breaks, shift changes or whenever

that space is left unattended.

21.9 RESCUE

The procedure for rescue in an emergency should be set out clearly in the permit-to-work,

with specific jobs allocated to specific persons.

Training should ensure that if a rescue becomes necessary, all persons concerned are

thoroughly familiar with the routine procedures through frequent practice drills.

The communication system must not rely on any method (for instance, blowing whistles)

which becomes impossible when breathing apparatus is being worn. Signals by means of

rope can also be unreliable since if the rope snags communication is lost.

At the same time, a danger alert must not rely on a signal given by the worker inside the

confined space, since if he is overcome suddenly he will be in no condition to give the alarm

and he may be working alone.

If space allows, a minimum of two men should enter a confined space when working out of

sight of the external observer. Communication must be of a fail-safe type. That is to say, if

the worker inside the confined space does NOT take the right action, the alarm is given. For

instance, if a periodic pre-arranged signal is NOT received at the end of the normal interval,

it could result in serious injury, or even death.

The essentials for rescuing someone from a confined space are that:

• the outside observer must have means of knowing immediately that a man is gassed or

has met with an accident.

• the rescue team, alerted by the observer, must get the casualty out into free air speedily.

• the casualty must be given first aid quickly, either at the work location or immediately he

is brought out into free air and the appropriate medical attention as soon thereafter as

possible.

rescue equipment

Rescue equipment should include breathing apparatus, resuscitation apparatus and oxygen.

It should also include:

• full body safety harnesses with

adequate length of rope taking account

of the workplace location.

• man winch.

• fire fighting apparatus.

• emergency escape breathing pack.

• audible alarm for summoning help.



PART TWO



• at least one set of suitable breathing

apparatus and emergency breathing

pack.

• first aid equipment.

• means of communication with the

surface observer.

• intrinsically safe hand torches or cap

lamps.

entry for rescue

Where the casualty has had an accident and is injured in an atmosphere certified on entry

as safe, rescuers can enter without breathing apparatus provided there are no indications

that the atmosphere has become unsafe.

Where, however, the casualty has collapsed and the cause is not known, then rescuers

must wear breathing apparatus.

This applies even if, when the person entered the confined space, it was certified as safe to

enter. The reason for the collapse could be an overall deterioration in the atmosphere since

entry was made, or a deterioration in the particular area where the casualty has been

overcome.

Apart from the paramount necessity of rescuing a worker who has been overcome, if gas is

suspected the emergency procedure must provide for the immediate evacuation of any other

person who may be within the confined space. A system of "audible" evacuate alarms

operated by the observer outside should always be installed if persons have to work out of

the sight of the observer at some distance from the openings.

If fire has broken out, or flammable gas is suspected, a pre-arranged procedure must

provide for the immediate summoning of the Civil Defense.

Emergency plans should be discussed with the local emergency services including fire,

police and ambulance so that the best use can be made of their expertise and facilities. If it

is practicable, there is great advantage in having an emergency practice with all the services

participating.

21.10 BREATHING APPARATUS

Breathing apparatus is used for work in confined spaces when the atmosphere is not safe to

breathe. The equipment consists of a properly fitted helmet or face piece, by means of which

the wearer can breathe uncontaminated air, either drawn from fresh air or supplied by

compressed air. All breathing apparatus supplied alter 30 June 1995 must carry the CE

mark.



PART TWO



The following are relevant types:

air line breathing apparatus

Supplied with compressed air by air line from a compressor or cylinders, in either case an

attendant must always be on duty at the supply end to monitor the uninterrupted supply of

compressed air. (see Fig.6)

If the air is supplied by a compressor, care

must be taken to see that the compressed

air delivered to the breathing apparatus

wearer is pure and uncontaminated by oil,

exhaust gases or any other pollutants.

Again the advantage is the unlimited supply

of air, the disadvantage is the presence of

the air line.

Where access to a confined space is too small for a man to enter wearing self-contained

breathing apparatus with cylinders. or where it is not possible to site a compressor unit

nearby, a mobile breathing apparatus unit (hose reel and trolley set) is useful.

self-contained breathing apparatus

Supplied by compressed air from cylinders

carried on the user’s back. This type is free

from the disadvantage of a trailing air line, and

it allows the man to he supplied with

compressed air or whatever mixture of gases is

suitable in the circumstances, and to move

freely The disadvantages are obvious, e.g.

• entry through a small man hole is not

possible wearing a cylinder pack: working in

a cramped space is impossible.

• the weight of the pack, (13 .18kg), imposes

a considerable extra work cad on the wearer

• the limited duration of the air in the cylinder,

which decreases in heavy work. (see Fig.7)

Fig. 6

Fig. 6 – Showing Air Line type Breathing Equipment.

Fig.7 - Showing Self Contained Breathing Apparatus.



PART TWO



escape breathing apparatus

Self-contained breathing apparatus with small

cylinder. Its purpose is simply to provide enough

respirable air in an irrespirable atmosphere to give

the wearer time to escape. (see Fig.8)

The breathing apparatus should be well fitting and

properly worn as accidents have occurred due to the

displacement of a face- or mouth-piece. It is better

When using an air line type of breathing apparatus,

to take filtered air from a supply at such a rate that a

positive pressure is maintained inside the face-piece.

All breathing apparatus must be thoroughly examined at least once every month by a

competent person authorised by certificate to carry out such examinations, and inspected,

tested and certified at intervals not exceeding six months.

Where practicable, the types of breathing apparatus used in an organisation should be

standardised. This reduces maintenance and spares problems, and simplifies operator

training.

21.11 PERSONNEL

People who will or may have to use breathing apparatus must be fit and not suffering from

any chronic or acute respiratory ailment. And they must he properly trained in the use of the

equipment.

Training, given by qualified person, should include:

instruction on :-

• the equipment, its mode of operation

and its limitations.

• the care and cleaning of apparatus.

• how to don the equipment, adjust the

face-piece and supply valves where

necessary, and to test for leaks around

the face-piece (beards and facial hair

may prevent an air tight seal).

• how to deal with malfunctions and

failures of equipment during use.

• the use of breathing apparatus in

emergency situations.

• the functions and limitations of escape

breathing apparatus.

• the hazards which necessitate the use

of breathing apparatus.

Maintenance and servicing of breathing apparatus should be in accordance with the

manufacturers instructions.

Fig.8 - Showing a 15 minute constant flow type escape set.



PART TWO



21.12 SEWERS

Additional to the precautions for confined spaces,

work in sewers necessitates safeguards against:

drowning and/or being swept away, 200mm of

water in a fast flowing sewer is difficult to stand

against and 600mm of water is a danger.

Conditions in a sewer can change very quickly,

and workers should be able to recognise

indications of danger such as: (see Fig.9)

• movement of air through the sewer.

• increase in depth or velocity of the stream.

• noise of approaching water.

In any of these conditions, immediate evacuation

must he carried out.

21.12.1 preliminary precautions during the planning of the work

should include:

• a system whereby a forecast of local weather conditions is obtained periodically.

• establishment of local control procedures in collaboration with sources of large amounts

of industrial effluents.

• collaboration with emergency services so that contingency plans can he established to

enable those in control of sewer operations to be alerted to the possible danger if, for

instance, harmful or flammable substances are released into the drains as a result of a

road accident or other emergency.

• Chains or bars should be fixed downstream of the working place before work starts.

• Wherever necessary for safety, running lines should be fixed for men to clip on to them.

21.13 BACTERIAL INFECTION & HYGIENE

21.13.1 leptospirosis (Weil’s Disease)

Infection can arise (mainly in foul sewers) from rats’ urine (Weil’s disease) from putrefying

solids or in discharges from hospitals and on occasion general discharges during epidemics

of contagious disease.

Fig.9 - Sewerage Operator entering a 9m deep sewer access manhole in Abu Dhabi. Note using life line and Full Breathing Apparatus.



PART TWO



A kind of infective jaundice, Weil’s disease or Leptospirosis is usually a mild illness if treated

in the early stages, but it can be a serious illness if it remains unrecognised and therefore

the patient is not given the appropriate treatment. It starts with flu-like symptoms, and to

safeguard against a wrong diagnosis, men who will be working in sewers should be provided

with a card to present to their doctor which informs him of the mans occupation.

The disease is not conveyed from person to person, so that a man’s family is not at risk, and

an attack confers a certain amount of immunity.

It is strongly recommended that anyone whose job brings him into possible contact with

sewage, should be inoculated against tetanus, poliomyelitis and hepatitis "A & B" and to

have the immunity maintained the whole time he is at work. Other precautions against all

these infections consist of good personal hygiene.

All workers should wear appropriate protective clothing (which is thoroughly cleaned after

each work period) and avoid exposing the skin, as infection can enter through abrasions.

Lanolin - based barrier cream should be used before work, and after work the hands, face

and forearms washed with hot water and soap. The nails should be scrubbed, but not the

skin, as this can roughen the skin surface and increase the risk of infection, and even the

smallest scratch should be washed and covered with antiseptic dressing, and every

accident, however trivial, reported to the person in charge of the work.

Eating, drinking and smoking must not be allowed until the personal hygiene rules have

been observed. Routine hygiene is easier to observe if mobile vans contain toilets, proper

hot water washing facilities and first aid on the site.

21.14 DETERIORATING ATMOSPHERE

The gases most commonly found in sewers are hydrogen sulphide (H2S), (flammable and

toxic) and methane (flammable and explosive in air). Both are generated during the

decomposition of organic matter and can be released into the air as workers wade through

the sewer so that a sewer certified as safe to enter may become unsafe as soon as men set

foot in it. Workers should be instructed to walk slowly and cause as little disturbance of

bottom sludge as possible.

The characteristic smell of rotten eggs indicates low concentrations of H2S, but at

concentrations high enough to be dangerous the gas paralyses the sense of smell, so the

absence of detectable smell is no guarantee of safety. H2S is an acute irritant to the eyes

and the respiratory passages massive inhalations can produce death by asphyxia.

Symptoms of exposure can be eye irritation, sickness, dizziness, choking and lack of

muscular control.

Note: Any time that workers experience symptoms such as eye irritation or any feeling of

illness, it should be taken to indicate a potentially dangerous situation and

precautionary measures instituted immediately.



PART TWO



21.15 SUBSTANCES WHICH MAY BE ENCOUNTERED IN A CONFINED SPACE

HAZARDOUS

SUBSTANCES

HAZARD OCCUPATIONAL

EXPOSURE

LIMIT(PPM)

(SEE NOTE 1)

LOWER

EXPLOSIVE

LIMIT %

PREVENTION IN CASE OF

FIRE

Acetylene

Asphyxiant and

narcotic. Highly

Flammable and

Explosive

____

2.5

Ventilation

Control

Cylinder Care

Dry Powder

Butane

Asphyxiant and

narcotic

Highly flammable

and explosive

LT (OES) 600

ST (OES) 750

1.6

Ventilation

Control

Cylinder Care

Dry Powder

Carbon Dioxide

Asphyxiant

LT (OES) 5,000

ST (OES)15,000

___

Ventilation

Control

___

Carbon

Monoxide

Toxic, flammable

and explosive

LT (OES) 50

ST (OES) 4000

12.5

Ventilation

Control

Dry Powder

Chlorine

Highly toxic and

corrosive.

Flammable by

reaction with

other materials

LT (OES) 0.5

ST (OES) 3.0

___

Ventilation

Control.

Complete

protective

suits.

Dry Powder

AFFF

Hydrogen

Sulphide

Highly Toxic

Flammable

LT (OES) 10

ST (OES) 15

4.3

Ventilation

Control

Dry Powder

Methane

Asphyxiant.

Highly

Flammable and

Explosive

___

4.1

Ventilation

Control

Dry Powder

Nitrogen

Oxides

Highly toxic and

corrosive

LT (OES) 3-25

ST (OES) 5.35

___

Ventilation

Control

___

Petrol

Toxic and highly

flammable

___

1.3

Ventilation

Control

Dry Powder

AFFF



PART TWO



HAZARDOUS

SUBSTANCES

HAZARD OCCUPATIONAL

EXPOSURE

LIMIT(PPM)

(SEE NOTE 1)

LOWER

EXPLOSIVE

LIMIT %

PREVENTION IN CASE OF

FIRE

Propane

Asphyxiant.

Highly

Flammable and

Explosive

___

2.3

Ventilation

Control

Cylinder Care

Dry Powder

Toulene

Toxic and

narcotic

Highly

flammable

LT (OES) 100

ST (OES) 150

1.2

Ventilation

Control

Impermeable

gloves

Dry Powder

Trichlor-

ethylene

Narcotic, may

emit highly toxic

fumes in

presence of hot

work

LT (MEL) 100

ST (MEL) 150

___

Ventilation

Control

Impermeable

gloves

Dry Powder

Welding fumes

Depending on

metal and rods

used. Mixture of

gases,metal and

oxide fumes

may contain

zinc, cadium or

lead

LT (OES) 5

generally

(other exposure

limits may apply)

___

Ventilation

control

Filter face

masks

Heat resistant

gloves and

overalls

Eye protection

___

White spirit

Flammable

LT (OES) 100

ST (OES) 125

1.1

Ventilation

Control

Dry Powder

Note: LT(MEL) Long - term maximum exposure limit (8 hour TWA)

ST(MEL) Short - term maximum exposure limit (15 minutes TWA)

LT(OES) Recommended long-term occupational exposure standard (8 hour TWA)

ST(OES) Recommended short-term occupational exposure standard (8 hours TWA)

P.P.M. Parts per million

TWA Time Waited Average calculated over 8 hours

SECTION 22

SECTION 22

ROAD WORKS & BRIDGES

INTRODUCTION 1


22.1 PLANNING 2

22.2 PERSONS AT RISK 3

22.3 RISKS AND HAZARDS 4

22.4 SAFETY PRECAUTIONS 6

22.5 TRAFFIC DIVERSIONS 10

22.6 TABLE 1 - positioning of signs and cones 15

22.7 FIGURE 1 - traffic diversion diagram 16

22.8 BRIDGE CONSTRUCTION 16

ROADWORKS SAFETY CHECKLIST

(ADM/H&S/CL/2.22/1)



PART TWO


ADM/H&S/Pt 2 01 March 2005 ROADWORKS & BRIDGES 1 of 19

SECTION 22

ROAD WORKS & BRIDGES

INTRODUCTION

This section is intended to cover safety aspects on all roadworks, as applied to both new highway

construction works and the reconstruction or resurfacing of existing highways

The term "Roadworks" includes the use of road surfacing materials containing cement, such as concrete and

mortars, and those containing bitumen, pitch or tar, such as hot rolled asphalt, cold asphalt, bituminous-

macadam and tar macadam, etc., and also the use of bitumens and tars in cold or hot liquid and spray

form. Various ancillary works and materials are also covered, including the use of waterbound macadam

and epoxy resins, the burning off and planning of existing bituminous road surfaces, the use of fuels such

as diesel oil, petrol and liquefied petroleum gas, as well as the many other maintenance activities such as

patching, surface dressing, drainage works and trench reinstatements, etc., carried out on our highways

every day.

The term "Bituminous Material" used in this section refers to any material containing bitumen, tar or pitch

as a binder and can also be considered to apply to bitumen or tar used in liquid form.


Abu Dhabi Traffic Police Department Regulations

ADM Roads Directorate Traffic Control Devices Manual, Section 7, Roadworks Traffic Control

ADM Roads Directorate - Bridge Design Manual



PART TWO



22.1 PLANNING

Road works can be a hazardous operation, both to contractors and to users of the public

highway. It is therefore essential to assess the various risks and to establish systems of

work which are both safe to contractors and the public.

22.1.1 generally

• it is essential to ensure road works wherever applicable are included in the pre tender

health and safety plan.

• associated safe systems of work and site rules should be included in the construction

health and safety plan which the main contractor must ensure is sufficiently developed

before the work is carried out.

• consider that pedestrian access and properties requiring vehicular access should at all

times be maintained.

• where work is planned which involves breaking up or opening any street or any

sewer drain or tunnel under it, this should be specified on the Notice of Intent and

approval must be given by all relevant authorities before commencing works.

• any part of the street to be obstructed by plant or materials must be adequately

signed and guarded, paying particular regard to the needs of the disabled.

• works must be supervised by a supervisor having prescribed qualifications and there

must be on site at all times at least one trained operative having prescribed

qualifications.

• it is important that the workforce is given appropriate induction training before

beginning work on site.

• visitors must be given sufficient instruction on relevant hazards before entering the

works area and be accompanied at all times by a trained person.

22.1.2 major roadworks sites

• on major roadworks sites, such as on motorways, designers should ensure that at

least one safe method of construction is identified, covering the workforce, others

involved in the project and members of the public.

• thorough planning is essential to ensure that adequate space and sufficient time is

available to enable the work to be carried out safely and efficiently.

• difficult space limitations should be avoided wherever possible. Sufficient space is

required for lateral and longitudinal safety zones, for the working area, for buffer

zones and for efficient traffic management systems. Although barriers for buffer and

safety zones should normally be of safe type, in certain circumstances, where there is

a high risk to operatives from motorway traffic, the use of concrete barriers may be

required. It is important, however, that these are used only with the agreement of the

police as damage to vehicles is inevitable if a collision occurs.



PART TWO



Sufficient space must also be provided for:

access for site transport

• where possible, well signed lead-in and lead-out coned off lanes should be provided

for site transport.

access for emergency services

• where possible, a clear traffic lane should be provided between the limits of the

"working space" and the live traffic, for use by the emergency services.

• where a clear lane cannot be provided, the site access lane will need to be used by

emergency services and, in the event of an accident blocking the running lanes, the

police may require the site access lane to be used by general traffic.

• where a site access lane cannot be provided, it will be necessary for an access

through the works area to be available for use in an emergency.

access across traffic lanes

• works personnel may need to get from one side of a traffic lane to the other.

• traffic lanes must never be crossed on foot and safe procedures must be introduced, such

as the provision of temporary bridges, or an approved route for authorised vehicles.

22.2 PERSONS AT RISK

In all safety matters pertaining to highway works, consideration must always be given to

operatives working on the highway and to the general public using the highway.

22.2.1 operatives working on the highway

• all construction workers engaged on highway works could be at risk. In addition, however, if

the highway works are on a road which is open to traffic, the risk is increased.

22.2.2 users of the public highway

• pedestrians and vehicle occupants passing in the vicinity of highway works could be at risk, as

could persons living or working nearby



PART TWO



22.3 RISKS AND HAZARDS

The risks to operatives and to members of the public can result in injuries caused by the following

hazards:

22.3.1 burns and fire risks

• many bituminous materials are supplied and used in hot form. Bearing in mind that hot rolled

asphalt is supplied at a temperature in the region of 135°C and liquid bitumen for surface

dressing at 150°C, burns can easily occur. There is also danger of burns from machinery and

hand tools used to lay hot bituminous materials or to heat existing road surfaces.

• the overheating of bitumen or tar, the misuse of fuels or the use of fuels in defective plant, can

create a serious fire risk. Heaters or burners used for heating existing road surfaces can,

if not properly operated and controlled, damage or set fire to adjacent property.

• skin contact with LPG can give cold burns, and cement, when wet, in the form of

concrete or mortar can cause serious burns.

22.3.2 carcinogenic nature of pitch, tar and mineral oils

• operatives who use pitch, tar or mineral oils, especially over a long period of time can

develop a skin cancer in the form of cancerous warts. The danger arises where any of these

materials is in frequent contact with the skin. When it occurs it is usually on the face, neck,

hands, arms or scrotum and may be cured by early treatment. Petroleum bitumens are not

considered to be a hazard in this respect.

• a further possible hazard from prolonged and constant contact with these same materials is

the contraction of dermatitis.

22.3.3 vehicle and plant accidents

• whenever vehicles or plant are moving or working alongside pedestrians or pedestrian

operatives on any roadworks site, there is a high accident potential.

Hazards under this heading fall into two general categories:

• the traffic accident type where a pedestrian operative is run over by plant or a vehicle.

Provision of a banksman should help to combat this type of hazard.

• the machinery/operative type of accident where injury is caused by the operation of the

plant or vehicle or the machinery in the plant or vehicle. For example, where an operative is

injured by unguarded machinery in a paving machine.

22.3.4 accidents to the public

• roadworks present an additional hazard to highway users over and above the ever present

traffic accident risk. However well roadworks are signed, the sudden appearance of

roadmen and plant in the road in front of moving traffic can be unexpected.

• the provision of a complete system of advance warning signs is absolutely essential,

together with a suitable traffic control system as detailed in this section.



PART TWO



22.3.5 eye hazards

• on works where hard surfaces or materials such as concrete, stone, rock or asphalt etc. are

being broken out by hand or machine or being formed with a hand tool such as a cold

chisel or a power driven tool, small chips or pieces of the material can be projected through

the air at high speed. If one or more of these pieces enters the eye, serious injury can result.

• a further danger can be caused by the inadvertent entry into the eye of other foreign

matter such as bitumen, oil, cement or other dusts.

• the use of epoxy resins adds a further hazard. If the curing agent gets into the eye,

permanent damage is likely.

22.3.6 falls

• operatives falling over any object or falling into excavations etc. account for many

accidents on roadworks sites. Falls from moving vehicles or plant are a further hazard.

22.3.7 hearing hazards

• where excessively noisy plant or other equipment is used permanent damage to hearing can

occur. Lower noise-levels, while not perhaps causing damage to hearing can be very

uncomfortable for operatives, causing tiredness, which in itself is another hazard.

• the reduction of noise at source and the provision and use of hearing protection can

remove this hazard. However, it must be appreciated that, if hearing protection is worn

when working close to fast moving traffic, the risk of a traffic accident is increased.

22.3.8 hazards from overhead and underground cables etc.

• the presence of underground electricity cables and other services can be a serious

hazard, particularly on existing highways.

• the location and identification of all underground and overhead mains and cables

must be established before works on site commence. (see Pt 2 Section 6)

22.3.9 back injuries

• back injuries can occur in working with bituminous materials and with concrete, especially

in lifting, raking and tamping.

• the use of correct lifting techniques and assuming correct postures will assist in

eliminating this most common of all hazards. (see Pt 2 section 8).

22.3.10 hazards from dusts, fumes and smoke

• the presence of various dusts is quite common on roadwork sites, the degree of

danger depending on the type of dust and the length of the time of inhalation. Dust

containing pitch can be carcinogenic, whilst cement dust can cause lung scarring, burns

and dermatitis. Silica dust can cause silicosis.



PART TWO



• fumes and smoke from hot bituminous materials are always present when these

materials are being used and they can cause discomfort and nausea to some operatives.

Careful assessment and monitoring of any dust, fume or smoke conditions is essential.

22.4 SAFETY PRECAUTIONS

The foregoing accident hazards can largely be prevented by careful planning and

exercising simple precautions.

22.4.1 personal hygiene

• transportable washing and toilet facilities should be provided on all sites to enable

operatives to wash off bituminous materials, cement or oils from the skin, especially

before eating or using toilet facilities and even smoking.

• personal hygiene is an absolutely essential step in combating the risk of dermatitis and

cancer.

• provision of adequate welfare facilities can be particularly difficult where work is of

short duration and should be catered for accordingly

• clean overalls are of little use if worn over clothing which is itself impregnated with

cement, oil or tar etc. Therefore, operatives' clothing should be kept reasonably clean

and free from cement, bituminous materials and dirt (see below)

22.4.2 protective clothing and equipment (also see Pt 2 section 12)

All operatives handling bituminous materials or concrete, and all others working on roadworks

sites should at all times wear:

safety helmets

• conspicuously coloured to make the wearer more visible to vehicle and plant operators.

All site personnel must wear a safety helmet at all times.

safety boots with steel toecaps

• with stout heat resisting soles

high visibility clothing

• essential to ensure that operatives are easily visible to all vehicle and plant drivers and

to passing traffic. Must be worn on dual carriageways with a speed limit of 80km/h or

above.

general covering/clothing

• cover exposed parts of the body in order to prevent contamination of the skin with

bituminous materials or concrete or cement.



PART TWO



• if clothing becomes impregnated with any bituminous material or concrete or cement, it

ceases to protect and may even cause the effects which it is intended to prevent as

oils, bituminous materials and cement work their way through clothing on to the skin.

• therefore, it is essential that all overalls, gloves etc. are regularly cleaned to remove

any contamination. Dry cleaning is probably the only effective method. In bad cases

of saturation with bituminous material or cement, the only remedy is disposal and

replacement.

gloves

• able to protect the wearer against heat, oil, tars, bitumens and concrete etc.

eye protection

• for such operations as cutting out, grinding, spraying bitumens or tar.

hearing protection

• noise from various sources can often be reduced by the provision of baffles or screens.

Noise from internal combustion engines can be reduced by the provision of silencers

or replacement of defective ones.

dust masks and breathing apparatus

• normally with roadworks the site is of an open nature and problems of fumes, smoke

and dusts are the exception rather than the rule.

• the problem may arise especially in confined sites such as a narrow road between tall

buildings or in tunnels or underpasses.

• dusts can generally be controlled by damping down but it may be necessary to provide

forced ventilation, e.g. air movers, and masks or breathing apparatus of a suitable type

for operatives.

• if breathing apparatus is required, proper selection and training is necessary. It is also

very restrictive on heavy manual work. Care must be exercised to ensure that the

protection provided is suitable for the particular problem experienced, be it dust, gas,

fumes or smoke.

22.4.3 overhead and underground services (also see Pt 2 section 6)

• the location of all mains and services must be established before carrying out any works

involving breaking out or excavating etc.

• Particular attention must be paid to electricity cables, both underground and overhead

and also to gas mains. In addition, it is advisable to verify the location of any given main

before commencing other excavation works in the locality.



PART TWO



22.4.4 plant (also see Pt 2 section 15)

• all plant manufacturers must provide safety recommendations and procedures in

respect of their product.

• it is essential that all users obtain such information and are familiar with and follow the

recommendations. A copy should always be kept with the particular machine.

• plant manufacturers must provide all necessary guards and safety devices for their

plant and if not, the plant must not be operated until a suitable protective guard has

been fitted.

• it is strongly recommended that all mobile plant and vehicles be painted a conspicuous

colour (e.g. bright golden yellow) and be equipped with rotating amber flashing

beacons.

• the operators of all plant and machinery must be properly trained and competent in the

use of the particular machine which they operate.

• it is the duty of all plant owners and operators to ensure that all safety devices such

as guards, brakes, hand-rails, warning lights and flashers etc. are always operating

satisfactorily or are reported immediately they become defective. The continued

use of plant or machines with defective safety devices must be prohibited.

• the misuse, overloading or the unauthorised riding on any plant or vehicle is forbidden

22.4.5 tools (also see Pt 2 Section 16)

• all tools used must be kept in good order and operators must be competent in their

use. Where necessary, training must be given.

22.4.6 fuels

• the fuels generally used on roadworks sites are diesel oil or gas oil, liquefied petroleum

gas and, more rarely, petrol.

• a "No Smoking" rule must be enforced where appropriate.

• any leakage from plant, or spillages, must be quickly remedied.

• a reasonable quantity of oil-absorbent chemical should be kept at all roadworks sites

for use on any spillage.

22.4.7 fire extinguishers

• fire extinguishers must be provided on all sites.

• generally dry powder, foam or CO2 extinguishers only should be used on oil, bitumen

or petrol fires; dry powder extinguishers should be used on LPG fires.

• water extinguishers should never be used on these types of fire.



PART TWO



22.4.8 pedestrian & warning barriers

• precautions must be taken to prevent persons

or plant from falling into any excavation.

(see Pt 2 section 23)

• particular precautions are required where the

public are involved, which will mean the fixing of

continuous rigid barriers to mark any temporary

footway and to protect pedestrians from traffic,

excavations and plant.

• guard rails should be at least 910mm above ground level and there should be toe boards

or another rail, approximately 150mm above the ground.

The following are examples of temporary barriers used to both protect the public and warn

vehicles.

22.4.9 general safety matters

The following additional general recommendations could all help to avert accidents:

• all vehicles and plant drivers and other occupants should vacate their vehicle by

the kerb side.

• all vehicles and plant should be equipped with two high intensity rear fog lamps that

are automatically switched on when reversing, plus an automatic audible reversing

alarm to warn operatives of the danger from a reversing vehicle. In addition, it is

highly desirable to have all reversing manoeuvres directed by a banksman located

towards the rear of the vehicle but within sight of the driver.

• in order to enable works to proceed smoothly on heavily used roads, consideration

should be given, where possible, to:

� working during light traffic flows only

� working at night

� working at weekends



PART TWO



• works carried out at night should always be floodlit, taking care not to dazzle or

blind oncoming traffic.

• when works are being carried out on a highway open to traffic, two-way working

of traffic flows should be maintained whenever possible. The minimum widths

recommended are 2.75m for one-way working and 5.5m for two-way working.

• steps should be taken to maintain both site safety and security outside working

hours in order to reduce the risk of accidents to the public, particularly to

inquisitive children. All vehicles and plant should be immobilised when not in use.

22.5 TRAFFIC DIVERSIONS

22.5.1 general requirements

Traffic Diversions must comply with any special requirements of the Police; the advice of

which should be sought where appropriate. In particular:

• it is essential and mandatory for the protection of operatives and the general public that

adequate signs are displayed giving highway users advance warning of road works.

• the sizes and positioning of signs and cones are dependant on the type of the road and

the relevant speed limits. For example, high speed roads require more and larger signs

displayed further in advance of the works, than minor or slower speed roads.

• if it is necessary to hold down signs, cones etc. because of wind problems, only

sandbags should be used. Hard heavy objects should not be used as, if hit by a moving

vehicle, they could become lethal missiles to the danger of persons or other vehicles

nearby.

• warning signs should be set so that their lower edge is at least 300mm clear of the

ground. This prevents any wording at the bottom of the sign from becoming too

dirty, or obscured.

• signs must be clearly visible to approaching drivers by both day and night, and in all

weather conditions.

• if there is not adequate lighting available to sufficiently illuminate the sign at night, then

reflective signs must be used.

22.5.2 works area

• the works area is the excavation, chamber opening, etc at which work will be carried

out.



PART TWO



22.5.3 working space

• the working space is the space around the works area where tools, excavated

material, equipment and plant, etc will need to be stored. It is also the space needed

to move around in to do the job.

• there must be sufficient working space to ensure that the movement and operation of

plant (e.g. swinging of jibs and excavator arms) is clear of passing traffic and is not

encroaching into the safety zone, or adjacent footway.

22.5.4 safety zones

• on any roadwork site, a space must be provided around the works for the storage of

spoil, tools, plant and equipment and to allow the safe movement and operation of plant.

• a safety zone, delineated by cones and lamps should be provided to protect operatives

from the traffic and to protect traffic from the road works.

• plant must not be allowed to encroach on to the safety zone, nor must operatives be

allowed to enter it other than to maintain the cones or safety signs.

a safety zone comprises:

� a lead-in taper of cones (T), which will vary with the speed limit and width of the

works. (see Table 1)

� a sideways clearance between the working space and moving traffic, which

must be at least 0.5 metres on roads with speeds up to 80 km/h and at least 1.2

metres on roads with speeds of 80 km/h and over.

� an exit taper which is always at 45o to the kerbside or road edge, and

� a traffic barrier, facing oncoming traffic, positioned within the coned-off area

to show the width of the works site. (This barrier may not be necessary if a

conspicuous vehicle is present).

N.B For roads with a speed limit of 80 km/h or more, an additional traffic barrier is required at

the end of the lead-in taper.



PART TWO



22.5.5 buffer zones

• on heavily used high-speed roads such as motorways and other principal roads, a

practice has been developed to provide buffer zones, to segregate opposing traffic

flows.

• the width of such buffer zones is preferably a full lane width of 3.65 metres, but should

be at least 1 metre. A full lane width has the added advantage of providing a separate

unused lane for access and emergency vehicles if breakdown or accident occurs.

• barriers should be used to delineate buffer zones. The ideal types in this case are

traffic cones, cats eye bollards or simple red and white coloured plastic pendant

markers, all of which are relatively harmless if hit by a vehicle.

traffic barriers

• traffic barriers should be constructed and should be continuous concrete traffic barriers,

used to indicate the road works and segregate the traffic from the works.

• their design should not cause a further hazard, if hit by a moving vehicle and they

should be of a conspicuous colour (e.g red or yellow stripes) and kept clean.



PART TWO



22.5.6 signage

advance signs

• Road Works Ahead’ signs shall be placed in advance of the road works and shall be the

first signs to be seen by the driver, as indicated in Table 1 (D).

Signs shown below are typical example of advance signs

ahead signs

• ‘Road Narrows Ahead’ signs shall be placed midway between the ‘Road Works Ahead'

signs and the beginning of the taper of traffic cones.

• ‘Keep Right’ or ‘Keep Left’ signs shall be placed at the beginning and end of the lead in

taper of cones.

• On roads with speed limits of 80km/h or more, all “ahead” signs should have the distance

to the works in meters printed on them as shown in Figure 1.

Signs shown below are typical example of ahead signs:



PART TWO



22.5.7 cones

• A line of traffic cones shall be positioned at a taper and should guide traffic past the

works, at a distance ahead of the works as indicated in Table 1 & Figure 1 (T).

• The maximum spacing distance of cones in longitudinal lengths of coning shall be no

more than 9 meters, but no less than 2 cones shall be used in any length between

tapers.

• Generally lead in tapers used with traffic control, and all exit tapers, shall be about 45° to

the kerb line with cones spaced 1.2 m apart and more specifically as below:

recommended cone spacing guide

Lead in taper: 1 in 10 or less Centre to centre cone spacing : 2 metres

1 in 20 4 metres

1 in 30 6 metres

Localised minor work area 1-2 metres

22.5.8 lamps

• road danger lamps must be provided for use at night, in poor daytime visibility and in bad

weather

• road danger lamps must not be higher than 1.2 metres above the road

flashing lamps (120 to 150 flashes per minute)

Only to be used if all of the following are satisfied:

• the road speed limit must be under 60 km per hour

• the road danger lamp must be within 50 metres of a street lamp

• the street must be illuminated

steady lamps

can be used on any road with or without street lighting.

22.5.9 pedestrians

• works on footways must leave at least 1.5m unobstructed width for temporary pedestrian

ways and should never be less than 1 m wide. Where this is not obtainable, an

alternative safe route for pedestrians must be provided.

• rigid barriers must be used to mark any temporary footway and to protect

pedestrians from traffic, excavations, plant and materials. Road danger lamps must

be placed at the ends of the barriers at night. Hand rails should be between 1.0

and 1.2m above ground level.



PART TWO



• if the temporary footway is in the carriageway, signing will be necessary for both

pedestrians and drivers. The provision of kerb ramps or raised footways may also be

necessary to help blind, elderly or disabled persons, or for those with prams or

wheelchairs.

22.6 TABLE 1 - positioning of signs and cones

details of signs and cones shall be as follows:

Details of lead-in cone tapers

Width of hazard (metres)

Type of road

Minimum

siting

distance

(D) of first

sign

in

advance

of works

(metres)

(Note 1)

Minimum

clear

visibility

to first

sign

(metres)

Minimum

size

of

signs

(mm)

Minimum

height

of

cones

(mm)

(Note 2) 1 2 3 4 5 6 7

Length of taper (T) in metres 13 26 39 52 65 78 91

Min. No. of cones 4 4 6 7 9 10 12

Single carriageway

road, restricted to

40km/h or less

20

to

45

60 600 450

Min. No. of lamps at night 3 3 5 6 8 9 11


Min. No. of cones 4 6 8 10 13 15 17

Single carriageway

road, restricted of

speeds 41km/h to

60km/h inclusive

45

to

110

60 750 450



Min. No. of cones 4 7 10 13 15 18 21

All-purpose dual

carriageway

road, restricted to

40km/h or less

110 to

275

60 750 450



Min. No. of cones 4 7 10 13 15 18 21

Single carriageway

road, with speed limit

80km/h or more

275

to

450

75 750 450



Min. No. of cones 5 9 12 16 19 23 26

All-purpose dual

carriageway

road, with speed limit

80km/h or more

725

to

1600

105 1200 750


Note 1: Minimum and normal maximum distance of the first sign (D) is given to allow a

range wherein the sign can be placed in a convenient position, bearing in mind

available space and visibility for drivers.

Note 2 : It may be appropriate to use the next larger size of cone in lead-in tapers (i.e.

750mm cones) in tapers where 450mm cones are indicated and 1 meter high

cones where 750mm cones are shown.



PART TWO



22.7 FIGURE 1 – example traffic diversion diagram

works on an 80km/h dual carriageway road – left hand lane closed :

22.8 BRIDGE CONSTRUCTION

22.8.1 general

• bridge construction activities, have significant health and safety implications. These

can arise from the nature of the processes, materials and chemicals used in

construction.

• this section raises relevant detailing issues and, in particular, those related to access

during bridge construction, operation and maintenance.

• the choice of a particular form of construction should be made with an appreciation of

the construction process and the need for maintenance. Where maintenance will be



PART TWO



carried out in high-risk areas, such as adjacent to high-speed traffic, the requirement

for such activity should be minimised.

• when working close to high-speed traffic, all relevant safety standards Roadworks as

explained in this chapter should be adhered to and in particular there should be a

safety zone for protection of the workforce in addition to the necessary working space.

• for motorways, this safety zone is a minimum of 12 m wide, so for bridge structures

with narrow verges the nearside lane will need to be closed when maintenance activity

takes place within the verge.

• other published guidance on health and safety issues in Bridge Construction should

be consulted as necessary. Further information can be obtained from:

� ADM Road Directorate - Bridge Design Manual

� ADM “HSE Codes of Practice Manual - Part Two Section 25 Falsework

� CIRIA Report 166, CDM Regulations - work sector guidance for designers which

has sections on bridge construction and bridge maintenance.

22.8.2 construction operations

• hazardous situations can be created where insufficient space is available to

undertake the work safely, eg where rectangular voids with restricted headroom have

been detailed in a deck and the soffit formwork has to be stripped out through a

narrow gap. In such cases, the use of permanent formwork or void formers should be

considered.

• badly detailed and congested reinforcement can also create construction difficulties.

• where ground conditions are unsuitable to support necessary falsework, consideration

should be given to supporting the falsework off the permanent works foundations.

• permanent formwork offers the advantage of protecting the areas beneath the bridge

deck against falling items, and avoids the need to send operatives below the deck to

remove temporary works.

22.8.3 access

general

• design/detailing considerations regarding general access to bridges may be affected

by:

� nature of the crossing (road, railway, river etc)

� adjacent landscaping (steep embankment slopes, large trees etc)

� location of buried services

� height of parapets and pilasters

� verge or pavement widths and surfacing



PART TWO



� street furniture including lighting columns.

• it is no longer normal practice to provide access manholes in road surfaces, chiefly for

safety reasons. Closing traffic lanes on busy highways creates risks for both drivers

and operatives. Traffic congestion resulting from lane closures creates additional

risks.

• access into box girders should be arranged from the abutments or, where the boxes

are discontinuous, through the soffit. Care must be taken to provide safe access to

locations in the soffit. Size of openings, ease of entry and rescue requirements

including anchor points also need to be considered. Heavy skews may create

particular difficulties, and special measures are needed for arch, cable-stayed and

suspension bridges.

internal access

• the size of openings at entry and between the cells of a structure should be decided

as part of the designer's consideration of hazards and risks.

• any minimum required by any applicable authority should be taken into account. It is

recommended that absolute minima of 460 mm x 410 mm or, if circular, 460 mm

diameter, should be provided unless there are other adequate means of egress.

• access size should allow necessary equipment (eg ventilation or stressing equipment

and/or a loaded stretcher) to be handled safely.

• the spacing of the access points influences this assessment. Platforms should be

provided at access and egress points along with appropriate lifting points.

• designers should avoid details that present hazards or create access problems. Box

girder structures present particular difficulties, as internal inspection is required. The

interior of a box girder must be recognised as a confined space. Associated

requirements include:

� trained personnel

� risk assessments

� emergency procedures

� controlled entry

� approved methods of working

� air monitoring.

• the designer/detailer should therefore consider:

� the means and ease of access

� spacing of manholes

� spacing of ventilation openings



PART TWO



� frequency of inspections

� methods of internal protection

� frequency of subsequent maintenance.

22.8.4 lighting and walkways

• The frequency of inspections and maintenance visits makes installation of permanent

lighting essential in large box girder bridges.

• they improve both safety and efficiency, thereby justifying the investment. The

infrequency of visits to the interiors of small bridges makes a permanent lighting

installation unnecessary, although the provision of intrinsically safe power-points

protected from misuse is appropriate.

• incorporation of permanent walkways and materials-handling routes can be

considered, but these in turn need to be maintained and require handrails if there is

likely to be a fall greater than 2 m (eg tops of piers).

22.8.5 seepage of water

• water may enter structures through faulty weatherproof seals, leaking road drainage

pipes or condensation.

• as part of their risk assessment, designers should minimise the hazards of slipping

on wet surfaces and of infection from the build-up of fungi in box girders by making

allowance for water to be dispersed.

• water ingress into smaller hollow sections should be considered even when no entry

is envisaged. Problems from deadweight effects have been known to occur.

22.8.6 security

• improved access to all parts of bridges makes security more difficult. The security

risks at each location of a new bridge should be assessed and appropriate measures

taken.

• secure doors/gates to the access routes may be necessary in some locations and

surveillance systems may need to be installed for full security.

• public access to girders over roads and railways etc should be prevented. For

example, permanent access ladders should stop out of reach from the ground, or

locked fold-down ladders should be provided.

SAFETY CHECKLIST - ROAD WORKS

Document No. Rev Date Section title Checklist

ADM/H&S/CL/2.22/1 01 March 2005 SAFETY CHECKLIST - ROADWORKS 1 of 1

for operatives

�� Have you planned how you will sign and guard the works?

�� Have all the appropriate authorities been notified?

�� Is everyone on the site wearing high-visibility clothing?

�� first warning sign?

�� What other signs are needed approaching the works?

�� What signs are needed at the works?

�� What length of coned taper is required?

�� How many lamps and cones will be needed?

�� What width of carriageway can be kept open and will it be enough for two-way traffic?

�� What width of footway can be kept open and will it be enough?

�� What form of traffic control needed?

�� Have any misleading permanent signs been covered? when work is in progress

�� If circumstances change, have you altered the signs, cones and lamps to suit?

�� Are signs, cones and lamps being regularly cleaned, maintained or replaced?

�� Has authorisation been obtained to accommodate any changed circumstances?

�� When traffic control changes are made at night or weekends, have the warning signs been changed?

�� Are traffic control arrangements reviewed and changed to reduce delays as works change?

�� Are the works adequately signed, guarded and lit for the overnight period?

�� Have you cleared away any spoil, etc. which may have spread onto the surrounding road or footway?

when work is complete and before you leave

�� Have all signs, cones and lamps been removed?

�� Have all permanent signs been restored?

�� Have appropriate authorities been notified that work is complete?

SECTION 23

SECTION 23

EXCAVATIONS

INTRODUCTION 1


23.1 HAZARDS 2

23.2 GROUND CONDITIONS 3

23.3 CHOICE OF SUPPORT METHODS 5

23.4 SUPPORT SYSTEMS 6

23.5 MAIN SAFETY REQUIREMENTS 10

23.6 MAINTENANCE 13

23.7 INSPECTION AND EXAMINATION 14

23.8 COFFERDAMS & CAISSONS 14

23.9 COFFERDAMS & CAISSONS - SAFETY PRECAUTIONS 17

SAFETY CHECKLIST FOR EXCAVATION WORKS

(ADM/H&S/CL/2.23/1)



PART TWO


ADM/H&S/Pt 2 01 March 2005 EXCAVATIONS 1 of 20

SECTION 23

EXCAVATIONS

INTRODUCTION

Almost all construction work involves some form of excavation for foundations, drains, sewers, etc.

These can be very deep and very dangerous. Every year, many people are killed, some actually

buried alive, in collapsed tunnels and trenches; many others are injured and there are several

reportable accidents during excavation and tunnelling operations. A relatively small collapse might

involve a cubic meter of soil, but a cubic meter of soil weighs over a ton. A man at the bottom of a

trench buried under this volume of material would be unable to breathe due to the pressure on his

chest and would quickly suffocate and die.

Deep excavations look dangerous - so precautions are usually taken. But most deaths occur in

excavations less than 2.5 meters deep. In fact, most accidents occur in ground conditions with no

visible defects; the trench sides seem clean and self-supporting. Despite appearances however, the

removal of material causes pressure relief - and introduces the conditions which lead to failure.

Rainwater or hot dry weather increase the chances of such failure.

Neither the shallowness of an excavation or the appearance of the ground should be automatically

taken as indications of safety. The evidence suggests that far too often they are.

It is impossible to forecast the behaviour of earth as its condition can change in a very short period of

time, and for this reason several factors, e.g. nature of soil, weather condition, size & method of

excavation and proximity of other structure, etc. need to be considered in the design and planning of

excavation work.

Considering all the above factors, Contractors should adopt the most appropriate method of

stabilising the sides of an excavation, example, battering, poling, sheeting, etc. for the safety of their

personnel.


Ministerial Order No.32 Year 1982 - Article (15).





PART TWO



23.1 HAZARDS

Excavation can result in serious injury, fatality or property damage due to the following

causes:

• collapse of earthwork due to lack

of, inadequate, or weak shoring.

• persons falling into excavations

due to lack of barriers or

inadequate fencing.

• asphyxiation from exhaust gases

that have collected in the bottom of

the excavation.

• soil from excavations not being

thrown clear of the sides that then

become overloaded and collapse.

• failure to maintain shoring,

particularly after rain and sand

storm.

• water seepage.

• persons working too close together.

• the striking of services, e.g. electricity/communication cables and oil/gas pipes.

Note: No soil whatever its structure, can be relied upon to support its own weight, and if a

trench or excavation cannot be made safe by slopping or battering the sides, some

form of support will be required.

• persons not being provided with, or not using

proper tools for the job.

• vehicles or plant too close to the edge, causing

the edge to collapse.

• workers in the excavation being struck by soil

or materials falling into the excavation.

• falls through unsafe means of access into, or

out of the excavation.

• workers being struck by excavating machinery,

e.g. excavator bucket.

• vehicles being driven into the excavation due

to driving errors, inadequate barriers, or the

absence of stop blocks.



PART TWO



23.2 GROUND CONDITIONS

23.2.1 general

Before commencing any excavation, it is important to identify the type of ground in which the

excavation is to be carried out. Detailed information may be available with the contract

documentation, or in the form of bore hole or trial pit logs carried out as part of the site

investigation.

When examining bore holes or trial pit information, particular importance should be paid to

the location of any water table. If the water table is going to be exposed by the excavation,

careful consideration will need to be given as to how it may affect the stability of the

excavation sides. Ground water can greatly affect the stability of any soil and, in particular,

non-cohesive materials. Water can also enter an excavation as surface run-off.

23.2.2 ground water

The presence of ground water is more difficult to deal with than surface water. It may affect

the sides of the excavation to the extent that, even if supported, wash out of material will

occur between the sheeting. In certain soil conditions, the bottom of the excavation can

become unstable and ‘boil’ with the inevitable total collapse of the trench.

If the ground is suitable, one of several ground dewatering techniques may be used. Such

methods involve either shallow well pumping or well-pointing. In either case, the pumping out

of water has the effect of lowering the ground water table to a level below that to which the

excavation is to be taken. (see Fig.1)

Where a water bearing strata overlays an impervious one and the depth of this impervious

strata is not too great, the use of sheet piling may be more effective and economical. The

piling, being substantially watertight, cuts off the water from the excavated area, thus

enabling the excavation to proceed in the dry. (see Fig.2)

(Fig 3) shows sump pumps being used to de-water an excavation.

Fig. 2

Header main: Original ground level

excavation

Well point Original water table

Fig.2 - Use of sheet piles to “cut off” excavation from water-logged ground.

.

1

2 2

3

2

New de-Watering Table

Fig.1 - Shallow well pointing

1. Permable strata. 2. Water. 3 Impermeable strata



PART TWO



23.2.3 temporary safe slopes

Battered sides or benches will generally be temporary stable if the slopes are as given in

table 1 below:-

Ground Conditions Safe temporary slopes

(degrees from the horizontal)

Dry Site Wet Site

BOULDERS 35/45 30/40

COBBLES 35/40 30/35

GRAVEL 30/40 10/30

SAND 30/35 10/30

SILT 20/40 5/20

SOFT CLAY 20/30 10/20

FIRM CLAY 30/40 20/25

STIFF CLAY 40/45 25/35

Fig.3 - Excavation dewatering using sump pumps.

Table 1



PART TWO



23.3 CHOICE OF SUPPORT METHOD

Factors such as availability of plant, site conditions and skill (or lack there of) of operatives

will probably determine the support method selected.

The choice lies mainly between:

• sheeting. waling and strutting (‘traditional’),.

• sheeting. waling and strutting (hydraulic struts),

• proprietary support systems,

• soldier pile support

In some soils the vertical excavation sides may stand unsupported for a short period. With

experienced and competent operatives this time may be used to erect the support system.

Excavation is dug to level over a short length and the support system installed without delay,

preferably from outside the trench. If the operatives need to enter the excavation during the

erection of the full support system, a protective cage or other interim support must be used.

The interim support must be quick and easy to erect to minimise risk

Choice of interim support could include:

• skeletal system of struts and walings giving immediate protection and forming part of the

final system of support.

• pinchers or protective cages.

The interim support is only intended to allow safe access for installation of the full support

system which should follow without delay. All other activities e.g. boning in, bottoming up etc.

should be done after the full support system is installed.

The exposed face of the excavation does not necessarily reflect the total ground condition.

An adjacent service trench or old well may contain weak saturated fill which could initiate a

failure. Where there are buried services adjacent to, or crossing the excavation, sides should

not usually be left unsupported, even for a short period.

In unstable ground the sheeting can be pre driven and the waling frames installed as

excavation progresses, or the sheeting can be driven progressively as excavation continues.

Both trench sheeting and proprietary boxes and slide rail systems can be adapted to this

method.

Beware that the excavated face at the end of the excavation does not collapse

inwards particularly under the action of the trenching machine straddling the trench.

The ‘free-standing’ time may be only a few minutes, if so. it is essential to install support as

the excavation progresses.

Where it is necessary to form a ‘stop- end’ to an excavation (e.g. where a trench is

constructed in two halves across a road) the operatives must be given guidance on the

bracing required for proper support to the stop-end sheeting.



PART TWO



• temporary framework on supports, or a

protective box or cage may be needed to

protect workers while they put in permanent

timbering.

• a box or cage can be moved forward as

timbering progresses.

• care must be taken to see that excavation

work does not jeopardise the stability of any

adjacent structure.

• precautions to protect workers and others

must be taken before and during any

excavation work.

23.4 SUPPORT SYSTEMS

Adequate support depends on the type of excavation, the nature of the ground, and ground

water conditions, generally speaking, timbering or shoring is not required for trenches or

excavations less than 1.2 m deep where there is no danger of any material falling or

collapsing.

For larger excavations, a survey of the soil prior to excavation by a trained and experienced

person will usually provide sufficient information for suitable methods of excavation and

support to be determined, and decided by a specialist engineer.

Adequate supplies of support materials should be available before the excavation

commences and must be sound, free from defects, of adequate strength, good construction ,

properly maintained and:-

• fixed securely to prevent displacement.

• only be erected/altered/dismantled

by competent workmen under

supervision.

• conventional timber shuttering or

steel trench sheets and adjustable

props should be used.

• props may be mechanical (jacks or

acrow’s) or hydraulic.

• precautions to protect workers and

others taken before and during any

excavation work.

23.4.1 types of support systems

There are many ways by which excavations can be made safe to work in, avoid settlement

to adjacent land and buildings and allow work to proceed with minimum hindrance. There

are, however, only the following four fundamental principles involved:-

battered sides

This is definitely the safest method as accidents from the collapse of properly designed and

executed battered systems are rare. (see Fig. 4)

Almost all soils can be excavated to a safe batter, provided that sufficient space is available

and a safe angle of repose known and adhered to. (See Table 1 on page 4)



PART TWO



double sided support

With this method of support, the

force exerted by the earth are

transmitted from one side of the

excavation to the other by walings

and horizontal struts, i.e. the forces

imposed by the earth on the

supporting materials are resisted

by the earth on the opposite side

of the excavation. Hence, if the

support is adequately designed, a

state of equilibrium is maintained

between the two sides.

(see Fig. 5)

Out of methods using a form of structural support,

this is the most satisfactory as only horizontal

forces are involved.

The method lends itself to the use of pre-designed

solutions and proprietory systems which are

installed in accordance with manufacturers

instructions. (see Fig.6)

Slope

Fig.4 - Battered trench

Beware:

Surface water can affect stability of

slopes and benches, endangering

the trench.

Intercept surface water to prevent it

entering trench. For some soils it

will be necessary to protect slopes

and horizontal surfaces adjacent to

trench.

Fig.5 - Double Sided Support – All forces horizontal

Fig.6 – Example of Double Sided Support



PART TWO



The following types of proprietary ground support equipment are available:

(a) Hydraulic waling frames (see Fig.7)

comprise two steel or aluminium beams

braced apart by struts containing

integral hydraulic rams. They can be

used for close or open sheeting

applications in trenches and for

supporting close sheeting in deep

excavations for which frames at various

levels may be required.

(b) Manhole shores (see Fig.8)

Are four-sided adjustable frames with

integral hydraulic rams and are intended for

supporting excavations for manholes,

foundations, small tanks and pits and similar

structures. Waling frames and manhole

shores should be supplied complete with

chains or other means by which they can be

hung from the sheeting or from other

frames.

(c) Trench boxes (see Fig.9)

These consist of modular side panels

strutted apart by adjustable struts to suit

the width of trench. Their height can be

increased by the addition of extension

panels. The location of the struts is

variable within limits, depending on the

ground clearance required. The lower

edges of the side panels are tapered to

form a cutting edge. Boxes should be

progressively dug in as the excavation

work proceeds, or they can be lowered

by an excavator or crane into a pre-dug

Fig.7 – Hydraulic Waling Frame

Fig.8 – Manhole Shore

Fig.9 – Trench Box



PART TWO



Earth pressure

Diagonal tensile force in anchor

trench. Where more than one box is required due to the depth, the boxesshould either

remain connected if lowered into a pre-dug trench or be connected/disconnected at

ground level by progressive excavation/backfilling. Install sufficient boxes so that the

full depth of the excavation is supported before people enter the excavation. If the

excavation is overdug, backfill needs to be placed between the excavation side and

the box to prevent both the risk of people falling into the gap and of rotation of the box

following ground movement. If required, trench sheets should be positioned at the

open ends to prevent material falling inwards. Some configurations of box may be

unstable when standing upright on the surface and should be either laid flat or 'dug in.

(d) Drag boxes (see Fig.10)

These comprise two flat-bottomed

side panels with tapered cutting

edges to their leading ends. They

are braced apart by tubular struts,

the leading strut being specially

strengthened to allow for the

dragging of the box by the

excavator. As the box is dragged

forwards the excavation behind it is

left open.

single sided with raking support

Only one face of the excavation is involved. Earth pressure from the excavated face is

resisted by transferring the load through the support material via wailings to either raking

shores or ground anchors. In the raking shore approach, an adequate foundation is needed

to transfer the loads involved to the excavated ground. (see Figs. 11 & 12)

Single sided cantilever support:

Whatever variation of this principle is

,

Vertical uplift force

Compressive force in struts

Earth pressure

Downward force

Fig.11 - Raking support Fig.12 - Use of ground anchors

Fig.10 – Drag Box



PART TWO



single sided cantilever support

Whatever variations of this principle is adopted, it should always be designed by suitably

qualified persons. The method can be used only:-

• in ground conditions which are sufficiently stable to provide the necessary resistance to

balance the overturning forces, or

• where the effect of superimposed loads and their stability is not critical.

All cantilevers will deflect to a degree. Such deflection will create risk to adjoining installations

and structures, roads etc. and their use in these circumstances should be avoided.

(see Figs. 13 & 14)

23.5 MAIN SAFETY REQUIREMENTS

23.5.1 access

• safe means of getting into and climbing out of an excavation must be provided.

• ladders must be securely fixed and properly maintained, and should permit quick and

easy escape in case of flooding or falls of materials.

Note: Using the walings and struts for access and egress purposes must be prohibited.

Overturning movement

Resisting movement Earth pressure

Anchor block

Earth pressure

Penetration to provide end fixing

Fig.13 - Free cantilever support Fig.14 - Propped cantilever support



PART TWO



23.5.2 barriers around excavations

• a safe means to enter and exit an excavation should be provided. Serious injuries have

occurred when workers have fallen from props that form part of the ground support when

these have been used to climb in and out of the excavation. This practice also carries risk

of disturbance to, and weakening of, the support.

• ladders should be positioned within the excavation at a height:base ratio not flatter than

4:1 and secured by tying at the upper end to prevent slipping. The upper end of the

ladder should project at least 1 m above ground level to ensure sufficient hand hold.

Ladders should be positioned where they will not be damaged by plant or from materials-

handling operations.

• where a person

may fall more than

2m, suitable

barriers must be

erected, but it is

sensible to erect

barriers even for

quite shallow

excavations where

anyone falling may

come to harm.

(see Fig.15)

• barriers should

also serve to keep

materials, plant

and equipment

away from the

edges of an

excavation.

• barriers may be removed to permit

access of men, plant and equipment,

etc., but should be replaced as soon

as possible.

• during darkness, the edges of an

excavation should be marked with

hazard warning lights, especially

where they are close to public

thoroughfares.

Fig.15 –

This excavation is supported by timbering and props.

Poling boards extend above the edge of the

excavation to act as toe boards,and guard rails are

provided to prevent falls into the excavation.

Safe access is provided by a tied ladder.

Exposed services are supported.

Tied ladder

Guard rail

Exposed services supported

Poling boards extended to act as toe-boards



PART TWO



• where excavation work is carried out on the roads, Traffic Police approval are necessary

and appropriate barricades and warning notices shall be erected.

recommended fencing and barrier arrangement around excavations in public area:

23.5.3 stop blocks

• where vehicles are used for tipping

materials into an excavation,

safety measures such as well

anchored stop blocks should be

used to prevent the vehicle

overrunning the edge. (see

Fig.16)

• these must be placed at a

sufficient distance from the edge to

avoid the danger of it breaking

away under the weight of vehicles.

Fig.16 - Stop Blocks to prevent vehicles being reversed into an excavation while tipping.



PART TWO



23.5.4 site lighting

The workplace must be adequately lit, in particular at access points and openings, and

whenever lifting operations take place.

23.5.5 ventilation

• excavations must be kept clear of suffocating, toxic or explosive gases.

• there may be natural gases like hydrogen sulphide, methane and methane and sulphur

dioxide, or exhaust gases from nearby plant, or leaks from nearby pipes or installations.

• these can seep through the soil and can accumulate at the bottom of an excavation,

below ground level.

• leakage of propane and butane from LPG cylinders is potentially very dangerous; the

gases will sink to the lowest point and form an explosive concentration.

• the most common method of ventilation is to blow clean air into the excavation in

sufficient volume to dissipate any gas accumulation.

23.6 MAINTENANCE

All excavation work requires careful watching, especially when they are first opened and

sides are unsupported , even when support work has been installed, constant vigilance is

essential.

Small movements of earth, resulting in movements in the timbering of no more than 6-12

mm are usually the only sign of the progressive weakening in cohesive soils which can

cause collapse. Such small movements can easily pass unnoticed but they are signs that

something is wrong.

Movements can be detected from slight distortion in timbering, bowing of poling boards and

walings, or signs of local crushing.

Main points to consider are:-

• all timber must be regularly checked, for if it

remains in position for any length of time, it

may dry out, shrink or rot.

• the only positive method of checking the

state of timber is to drill small holes with an

auger.

• ground, too, may dry out and shrink - which

loosens the timbering.

• the soil face; wedges or telescopic struts holding them must always be kept tight.

• during bad weather soil heaps tend to

slump, and loose boulders or masonry

may fall into the excavation.

• heavy vehicles should not be allowed

near the edge of excavations unless

the support work has been specially

designed to permit it.

• when loads are being moved into or out of the excavation by skip or bucket, care should be taken to avoid damage to struts or walings.



PART TWO



• raking or angle, struts should all be regularly examined for signs of having been

dislodged.

• safety helmets and safety boots should be worn at all ties since earth and other material

can slide down or fall.

23.7 INSPECTION AND EXAMINATION

• excavations must be inspected by an experienced and competent person, before work

starts, at least once a day, and before each shift.

• excavations must be thoroughly examined weekly (every seven days) and after

substantial collapse or damage.

23.8 COFFERDAMS AND CAISSONS

23.8.1 introduction

Their function is to provide a space down to foundation level from which water is excluded

sufficiently to permit the descent of workmen, plant, etc. the removal of spoil and the

execution of the permanent work.

23.8.2 choice between cofferdams and caissons

The main difference between a cofferdam and a caisson is that although they are both

enclosures for the purpose of excluding water and soil from a work during construction, a

cofferdam may be generally a temporary structure, part or all of which is removed after

construction, whereas a caisson is primarily a permanent structure or one which is

subsequently incorporated in the permanent work.

The chief factors influencing the type of construction used are ground conditions and the

depth to which the work is to be carried.

Where the work can be safely carried out in free air, cofferdams or open caissons may be

used.

For deep cofferdams it may be preferable not to lower the water below a certain level, the

last stages of excavation, concreting and if necessary strutting being carried out through

water.

23.8.3 cofferdams

introduction

The purpose of a cofferdam is to exclude soil and water from an area in which it is required

to carry out construction to a depth below the surface. Total exclusion of water is often not



PART TWO



necessary and in some instances is not possible, but the effects of water ingress must be

taken into account.

There are two principal approaches to cofferdam design. Single skin structures are most

common, but for very large or deep excavations and marine works, double wall or cellular

cofferdams may be preferred.

The design of a cofferdam is carried out in the same manner as a retaining wall and

consequently, the same rules apply.

23.8.3 selection of cofferdam

In the selection of a suitable cofferdam type for a given duty the following factors should be taken into account:

• whether a land cofferdam or water cofferdam is required

• nature of the structure to be built within the cofferdam

• plan dimensions of the working area required inside the cofferdam

• total depth of soil and/or water to be retained

• soil conditions below and above foundation level

• groundwater levels and their fluctuation, and for water cofferdams the tidal, seasonal and

flood levels

• for water cofferdams, the strength of the current, wave action and scour before, during

and after construction

• possible effects of the cofferdam construction on existing buildings or other structures

close to it

• availability of materials

• methods of constructing and dismantling the cofferdam

• time available for construction of the cofferdam

• noise, vibration, fumes and fire risk

• accessibility especially for cofferdams in water

Certain of the types are suitable for both land and water cofferdams, while others are

applicable to one or the other only. The extent of the working area will further limit the

choice. When the depth is great, the soil and water level conditions will be particularly

significant.

Possibilities that can be considered are:

a) combinations of cofferdam types

b) final excavation carried out underwater

c) special dewatering methods



PART TWO



For extreme depths, depending on the soil conditions, it may be necessary to resort to

monolith or caisson construction.

cofferdam support frames

timber framing steel framing

23.8.4 selection of caissons

Each deep foundation is a special case and no fixed rules can be laid down for guidance in

the choice of the type of structure to be used. Frequently, the factors of time and cost will

govern the choice of type as much as conditions of ground and water.

A caisson in free air or an open caisson may be employed where it is necessary to establish

the foundation at a considerable depth below surface water or ground level, e.g. to depths

which may in exceptional cases exceed 45 m. Excavation will usually be done by grabbing.

Caissons are not commonly employed if the ground contains a large proportion of very stiff

clay, owing to the great weight of the structure required to overcome skin friction in such

ground, but skin friction may be reduced by lubrication with water or clay grouts. Open

caissons are difficult to pass through rock or ground containing large boulders.

Caissons may be used for a wide variety of ground conditions. These include the following:



PART TWO



a) in water-bearing ground where it is required to inspect the soil at foundation level, and

where alternative means of dewatering are impracticable;

b) where the caisson is to be sunk through water-bearing strata containing rock either as

beds or as large boulders;

c) where the caisson is to be used as a shaft in which an opening is to be made in a

water-bearing zone, for the purpose of driving or receiving a tunnel; (see Pt 2 section

24)-Tunnelling

d) where it is necessary to avoid subsidence of adjacent ground or structures due to

inflow of soil into the caisson, as may happen with open caissons sunk by grabbing.

Reinforced concrete caissons (monoliths) may be preferable to steel caissons during sinking

because of their greater weight.

Steel caissons usually present fewer problems during their construction than reinforced

concrete caissons.

23.9 COFFERDAMS AND CAISSONS - SAFETY PRECAUTIONS

The following standards and recommendations for the safety of personnel are particularly

applicable to construction work in cofferdams and caissons.

23.9.1 general public

The contractor will need at all times to ensure that members of the public are protected from

any accident or injury arising from work operations.

23.9.2 site supervision

A competent person, properly qualified and experienced, should be appointed to supervise

the work operations. This person should be capable of recognising and assessing any

potential dangers as they arise,

e.g. unexpected ground conditions that may require a change in construction technique, or

unusual smells which may indicate the presence of noxious or dangerous gases.

23.9.3 PPE (also see Pt 2 section 12) -PPE

helmets

The need for protective helmets is particularly important for those in piling gangs and

persons engaged in working in excavations or in areas with confined headroom.

safety footwear

Should be reinforced by steel not only in the toes but also in the soles, to prevent injury by

sharp objects concealed under the spoil.



PART TWO



safety harnesses

Should be worn by men required to climb up frames or other equipment

ear defenders

Noise levels during certain operations can be injurious to hearing and so require the wearing

of ear protectors.

23.9.9 chemical grouts

Some chemicals used as additives in grouts are highly toxic although in practice they are

used in such small quantities that there is no risk from the grout itself. However, the additives

themselves are highly toxic and the manufacturer's safe-handling instructions should be

followed. In particular, water soluble acrylamide requires very stringent safety precautions to

avoid skin contact, breathing dust, mist or vapour. It requires clean work clothes every day

which should consist of long-sleeved overalls, head covering, rubber or plastics gloves and

rubber footwear. A respirator and goggles are also required when changing the grout or

cleaning up chemical spills. The manufacturer's instructions should be observed for the full

safety requirements.

23.9.4 ladders

Ladders should be of substantial construction and secured to prevent slipping. They should

not rise more than 9 m without intermediate platforms (see Pt 2 section 29)-Scaffolding

23.9.5 electricity

Supply of electric power for lighting and hand tools should be at a voltage not exceeding 65

V to earth.

Where higher voltages are required for supply to machinery, the supply cable should either

be armoured or enclosed in continuous metal conduit, (see Pt 2 section 7) for electrical

installations

23.9.6 fire

Particular attention should be paid to fire hazard on working platforms. Drip trays should be

provided for oildrums and under machinery; fire extinguishers have to be provided and kept

in working order.

23.9.7 air testing

In deep and confined excavations a continuous routine should be established for testing for

noxious gases and deficiency of oxygen.

23.9.8 excluding water from excavations (pump sumps)

Although a sheet pile wall can prevent the ingress of water into an excavation, it is not

possible to give any guarantee that a cofferdam will be watertight. In order to deal with any



PART TWO



water which enters the excavation it is often desirable to install a drainage system which can

channel water to a sump from which the water can be pumped away.

As the hydraulic gradient adjacent to the corner of a cofferdam is at its largest, it is advisable

to place any sumps at excavation level as far as possible from any corner and wall.

It should not be forgotten that pumps are able to remove soil as well as water and a suction

hose laid in the bottom of a cofferdam can disturb the base of the excavation with

subsequent movement of the wall if the hose is badly located. Consideration should be given

to forming a sump using a perforated drum into which the hose can be fixed to limit damage.

23.9.11 tide work, work over or adjacent to water (also see Pt 2 section 28.0)

• Taking into account the circumstances, in some cases, especially in flowing water,

lifebelts with lines attached should be provided and be readily available at positions

where they are likely to be needed.

• Buoyed lines will be desirable at a suitable distance from the work to give anyone who

falls in an adequate chance of securing a handhold while awaiting rescue

• Particular attention is drawn to the need for adequate floodlighting at night at least

within the limits of the buoyed lines.

• Adequate guard-rails should be provided to jetties or floating stages.

• In fast flowing waters or tidal waters a safety boat, boatmen and lifebelts at conspicuous

positions should be provided.

• All men working over water should be required to wear a buoyant life-jacket.

23.9.10 land cofferdams

If the sheeting to the cofferdams extends less than 1 m above ground level, guard-rails

should be provided to form a barrier at the edge; toe-boards should also be provided. When

a land cofferdam is located near to a watercourse, historical flood levels should be checked

to ensure that the cofferdam is adequate to withstand exceptional flooding.

23.9.12 concrete, steel and steel sheet piling (also see Pt 2 section 26) -Piling

The safety precautions necessary in handling steel piles and interlocking steel sheet piling

are also applicable to precast concrete piles.

The pile topman who guides the pile into the interlock of a pile should be provided with a

fenced platform which can often be built onto the temporary timber trestle used for pitching

the piles in panels or provided with a safety harness attached to permanent static line. If a

man-riding skip used for access is suspended from a crane, then the hoisting mechanism of

the crane has to be provided with automatic braking facilities.

Only skilled and experienced men with adequate and safe equipment should be required to

carry out the potentially hazardous operation of interlocking steel sheet piles.



PART TWO



The extraction of steel sheet piles should be carried out with an extractor of adequate size,

so that the performance is not mainly dependent on the pull of the crane and there is no

danger of overloading or overturning the crane.

SAFETY CHECKLIST - EXCAVATION WORK


ADM/H&S/CL/2.23/1 01 March 2005 SAFETY CHECKLIST - EXCAVATION WORK 1 of 2

SAFETY CHECKLIST FOR EXCAVATION WORKS

Final planning checks

�� excavator adequate for lifting requirements

�� spoil to be retained on site or disposed of

�� storage areas provided for spoil, trench supports materials, plant and permanent work

materials

�� materials ordered for trench support

�� imported backfill and materials ordered (compactors, compressors, generators, lighting, traffic

lights and signs etc.)

�� materials ordered for access to works and for guarding works

�� special plant ordered (dewatering equipment, pumps etc.) special plant ordered (dewatering

equipment, pumps etc.)

�� details of buried services received from appropriate authorities

�� surveys of adjacent structures complete

�� requirements of the Noise at Work section complied with

Final design checks

�� is there any new information? For example, on ground conditions

�� is designed based on latest specification?

�� Is the sketch for the foremen or ganger complete, clear and unambigous?

�� If there is a detailed drawing for the Temporary Works Co - Ordinator and does it show

everything?

�� have the temporary works quantities been taken off for the site engineer?

�� are the design assumptions shown on drawings and calculation sheets correct?

�� Is the designers name given on drawings and calculation sheets?

�� will the necessary plant be available?

�� have site variation been covered? For example, access roads?

�� does design allow sufficient working room?

SAFETY CHECKLIST - EXCAVATION WORK


ADM/H&S/CL/2.23/1 01 March 2005 SAFETY CHECKLIST - EXCAVATION WORK 2 of 2

Checks during construction (at least daily)

�� hard hats being worn �� competent operators

�� Wedges tight �� stop for dumber

�� tipping area clear of men �� struts square to wailing

�� experienced supervisors �� ground as assumed

�� crossing services supported �� signs and warning lights

�� wailings supported

�� no excessive deflection

�� safe extraction of sheeting �� water table as assumed

�� exhaust clear of trench �� safe support during compaction

�� clear of spoil for 1.5m �� proper slinging arrangements

�� fences adequate �� foot bridge safe

�� trench sides clear of hazard �� visibility adequate

�� timber not damaged �� crossing services located and marked

ahead of excavator

�� stable spoil heaps �� wailings correctly sized and spaced

�� ground not deteriorating

SECTION 24

SECTION 24

TUNNELLING & SHAFT SINKING INTRODUCTION 1


24.1 GENERAL REQUIREMENTS 2

24.2 WORK PROCEDURES 2

24.3 NOISE 6

24.4 VENTILATION 6

24.5 DUST 8

24.6 ILLUMINATION 9

24.7 ATMOSPHERIC CONDITIONS 11

24.8 LIFTING EQUIPMENT 12

24.9 SHAFTS 13

24.10 SMALL HEADINGS AND SMALL TUNNELS 16

24.11 GROUND SUPPORT 17



PART TWO


ADM/H&S/Pt 2 01 March 2005 TUNNELLING 1 of 20

SECTION 24

TUNNELLING & SHAFT SINKING

INTRODUCTION

This section makes recommendations for and gives guidance on Health & Safety practices in shaft

sinking and tunnelling.

The standards and guidelines also include health & safety recommendations that are particularly

relevant to the type of shaft sinking and tunnelling that is carried in the Emirate of Abu Dhabi.


None applicable specifically for Tunnel and Shaft Sinking Operations



PART TWO



24.1 GENERAL REQUIREMENTS

24.1.1 workers

All persons employed should have a high standard of physical fitness. It is desirable that

all persons working underground and all plant operators and banksmen be not less than

18 years old.

24.1.2 training

All employees involved in underground construction must be trained to recognise and

respond to hazards associated with this type of work. Training should be tailored to the

specific requirements of the jobsite and include any unique issues or requirements.

The following subjects should be part of employee induction training program :

• Likely hazards and risks

• Site rules and prohibited activities

• Devised safe methods of working

• Air monitoring and ventilation

• Illumination

• Communications

• Flood control

• Personal protective equipment

• Emergency procedures, including evacuation

• Check-in/check-out procedures

• Fire prevention and protection

• Mechanical equipment

24.1.3 personal protective equipment

In tunnelling construction works, the wearing of some personal protective equipment is

inevitable. After residual risks have been identified, PPE should be selected by

considering standards and requirements in (see Pt 2 section 12) - specific for persons

involved.

24.2 WORK PROCEDURES

24.2.1 communication

above ground person

• Any time an employee is working underground, the employer must maintain at least one

designated person on duty above ground.



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• Designated person must maintain a check-in/check-out procedure for keeping an

accurate count of persons underground and to prevent unauthorized persons from

gaining access to the site.

• Designated person is responsible, calling for immediate assistance and summoning

emergency aid if needed.

audible signals

• Audible signals by bell, whistle, or other device can be used for routine operations

such as hoisting and lowering in a shaft. Signals should be distinctive and sufficiently

loud to avoid confusion with any incidental or accidental noises.

The recommended code is:

� stop: one signal

� lower: two signals

� hoist: three signals

� hoist personnel: four signals

� emergency: continuous

• If natural unassisted voice communication is ineffective at any time, a power-assisted

means must be used to ensure communication between the work face, the bottom of

the shaft, and above ground.

visual signals

• signals to machine operators should normally be given only by banksmen.

• all persons involved in the operations should be made familiar with the code through

induction training and/or other means such as toolbox talks.

lone working

• an individual employee working underground, not able to be observed by other

employees, is only permissible if he is in range of voice communication. In this case the

employer must provide an effective means of obtaining assistance in the event of an

emergency.

24.2.2 reporting hazards and risks

Any hazardous conditions or occurrences that might affect workers safety must be recorded

and employer must notify all oncoming shifts of occurrences or conditions e.g equipment

failures, movement/collapse, flooding, fires, or release of gas, any abnormal ground levels,

tidal levels and rainfall.



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24.2.3 control of access and egress

The employer must maintain safe access to and egress from all workstations at the

construction site to protect employees from potential hazards, such as being struck by

excavators or other moving equipment.

To help control access, all unused openings must be tightly covered, bulk headed,

barricaded, or fenced off, and posted with warning signs that read, "Keep Out" or similar.

24.2.4 heat stress and exhaustion

Mechanization, ventilation and job rotation should be arranged to reduce the risk of heat

stress and exhaustion. Adequate supplies of cold potable water should be made

available.

24.2.5 first aid (also see Pt 1 section 6)

first aider

It is essential that persons trained in first aid and capable of responding rapidly to any

incident be available on each shift during working hours.

emergency response

All personnel should be told that, in the event of serious injury, a casualty should be

moved only by a trained first-aider, unless there is the immediate risk of further injury.

first aid facilities

Sufficient first aid boxes should be provided, designed to protect the contents as far as

possible from damp and dirt. They should be clearly identified and be readily accessible

to working areas and should be in the charge of designated first-aiders on each shift.

stretchers

Stretchers (and blankets) suitable for the confined space of a tunnel should be provided

and maintained. They should be readily accessible for use in working areas in an

emergency, and should be protected against dirt and damp. In particular, where access

to a tunnel is by a shaft, stretchers should, where practicable, be stored at tunnel level.

Appropriate means of transporting an injured person to the surface should be provided.

Lifting arrangements in shafts should take this into account.

24.2.6 evacuation

Good communications are essential between the working areas and the surface. A clear

plan of action should be formulated for the rapid transfer of any injured persons from

working areas and to ensure that ambulances can reach shaft tops or other access

points quickly. Clear instructions should be given to all persons on the procedures to be

adopted for evacuating tunnels in an emergency.



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standards

Every employer must ensure that all employees:

• working in the tunnel have a portable hand lamp or cap lamp unless natural light or an

emergency lighting system provides adequate illumination.

• be provided with an escape type breathing apparatus and approved gas monitor if the

area they are working in areas which may present a gas or smoke hazard.

• If 25 or more employees work underground at any one time, the employer must provide a

fully equipped and trained rescue team together with appropriate vehicle to transport an

injured person to the nearest hospital.

• If less than 25 employees work underground, there must be a direct means of

communication with the local emergency services.

• If a shaft is used as the means of egress, the employer must arrange for a readily

available lifting capability unless the regular lifting means will function in the event of a

power failure.

24.2.7 fire prevention and control

general

• Open flames and fires are prohibited in underground construction areas except as

permitted for welding, cutting, or other hot work operations.

• Smoking is prohibited at all times and notices to this effect should be prominently

displayed.

• Fire extinguishers or equivalent extinguishing means must be available at the head and

work areas.

• All underground structures and those within 30 m of an opening to the underground must

be constructed of materials with a fire resistance rating of at least one hour. Also, non

flammable or combustible material may not be stored above ground within 30 m of any

access point to an underground operation.

• Petrol may not be underground at any time for any purpose and internal combustion

engines (except diesel-powered engines on mobile equipment) are prohibited

underground.

• Oil, grease, and diesel fuel stored underground must be kept in tightly sealed containers

in fire-resistant areas away from passage ways.

hot works

• Acetylene and liquefied petroleum gas may be used underground for welding, cutting,

and other hot work if all requirements/standards pertaining to such activities are met.

(see Pt 2 section 27 )-welding



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• Only enough fuel gas and oxygen cylinders for welding, cutting, or hot work during a 24-

hour period are allowed underground.

• Non combustible barriers must be installed below such activities if they are performed in

or over a shaft or rise.

use of diesel fuel

Specific requirements apply to the use of diesel fuel in underground construction

operations, as follows:

• A surface level tank holding diesel fuel to be pumped to an underground storage site

must have a maximum capacity no greater than the amount of fuel required to supply

underground equipment for 24 hours.

• A surface level tank must be connected to the underground fueling station by an

acceptable pipe or hose system controlled at the surface by a valve and at the bottom

by a hose nozzle.

• The transfer pipe must remain empty at all times except when transferring diesel fuel.

• All hoisting operations in the shaft must be suspended during refueling operations if

the supply piping in the shaft is not protected from potential damage.

24.3 NOISE

24.3.1 general

The effects of noise are intensified in tunnels because the confined space increases the

reverberant sound field that can be developed by noisy plant and equipment, tools or

processes. This is especially problematic if persons have to work close to, or use, noisy

tools, e.g. pneumatic picks producing a sound pressure level of 110dB(A) to 115dB(A).

• Since there is insufficient space to reduce the level of noise emission by confinement

and/or containment retrospectively, all machines and tools should be selected on the

basis of risk assessment to be designed to eliminate or reduce the noise at

source with minimum operator exposure.

• Thereafter a management system should be established to :

a) confirm the adequacy of the noise and vibration controls

b) continually identify significant residual noise sources; and

c) ensure regular maintenance checks and replacement or repair

Pt 2 section 3 gives guidance on how noise arising from worksites affects site personnel

and others. It contains information on noise emission from tools, plant and equipment



PART TWO



that could be useful at the planning stage in reducing noise and recommendations for the

control of noise.

24.4 VENTILATION

24.4.1 general

• polluted air must be removed from tunnel continually.

• if natural ventilation does not provide the necessary air quality through sufficient air

volume and air flow, the employer must provide mechanical ventilation to ensure that

each employee working underground has at least 200 cubic feet (5.7m3) of fresh air per

minute.

• the inlet to the ventilation system must be positioned away from petrol and diesel

engines, hazardous materials and dust fumes.

• the outlet from ventilation system should be positioned such that it would free to

disperse any harmful substances away from the work area.

24.4.2 cooling

• the volume of fresh air required for cooling purposes should be examined carefully

to ensure a sufficient flow of air to keep the working temperature within acceptable

limits.

24.4.3 selection

• The methods of ventilation adopted should be in accordance with the hazards

presented by each tunnelling situation. Factors that should be considered include:

� the numbers of face workers

� the work locations

� the length, size and gradient of drive

� the presence of water, dust or fumes

� the presence of methane

� whether drilling and firing will be taking place

� the amount of waste heat generated by mechanised tunneling operations.

• In a tunnel advancing as a single face, fresh air supply to face workers is likely to be

the primary consideration; but where there are many areas of work the requirements

for the supply of fresh air and ventilation will vary.



PART TWO



• Conventional forcing, exhausting or overlap systems are employed in most tunnels,

and the particular machinery and environmental conditions should determine which is

the most suitable.

• Where dust is a major problem, the system should be designed to control dust and

should incorporate filters to clean the dusty air before readmission to the general body

of airflow.

• The effect of heat added to the air from installed machinery, and the increase in

humidity, can be reduced by using forcing systems having high local air velocities and

by carefully controlling the amount of water used for dust suppression.

24.4.4 ventilation systems

The ventilation system should be simple and designed to be moved forward or extended

with the progress of tunneling.

Ventilation systems can include one or more of the following:

a) a forced supply of fresh air, exhaust being through the tunnel and access ways

b) extraction of polluted air from the tunnels, fresh air being drawn into the tunnel due to

the reduction in pressure caused by the exhaust ventilation

c) alternation of forced supply and extraction.

d) air movers to assist locally and to eliminate stagnant pockets. If air movers are used

locally, care should be taken to ensure that these will not cause recirculation.

24.4.5 siting of fans

Air intake and exhaust fans on the surface should be sited well away from sources of

contamination

24.4.6 earthing

The movement of dust and gases through a ventilation system can cause a dangerous

build-up of static electricity. All ducts, fan bodies, casings and support structures should

be properly bonded to each other and to an adequate earth. Air movers and venturi

devices should also be earthed.

methane

Where an extraction ventilation system is in use and there is a risk of methane being

encountered, the design and construction of the system should take into account the

hazard of methane passing through fans and fan motors. The methane concentration in

the ducts should be continuously monitored.

• If methane is likely, the fans should be explosion-protected. It should be noted that

methane concentration in the tunnel is likely to increase when the ventilation system



PART TWO



is shut down. Explosion protection of the extraction system in many cases involves

the use of bifurcated fans with non-incendive impeller rings.

dust

• To prevent dust particles migrating back against the main body of airflow, the air

velocity in any section of tunnel should be not less than 0.5 m/s. Ventilation

calculations should use this as a minimum value. The efficiency of the ventilation

system should be tested periodically and any deterioration in performance should

be remedied.

Note:This guidance in should be followed where extraction ventilation is necessary to

control dust emissions and also applies where methane could be present.

24.5 DUST

24.5.1 general

Dust generated from tunneling works should be suppressed at source as far as is

practicable. Its spread should be controlled by methods such as water spraying, water

infusion and extraction ventilation.

24.5.2 effects of dust

One direct physical effect of dust is reduced visibility, which increases the risk of

accidents related to moving machinery and equipment.

The exposure of persons to various kinds of mineral dust can produce a variety of lung

conditions. Among the more serious conditions is pneumoconiosis.

24.5.3 control and removal of dust

High-pressure water jets at the source are the most effective and positive means of

dust suppression.

Respirable dust that has become airborne cannot be controlled by water sprays. However,

these can be used whilst handling spoil to suppress dust by preventing it from becoming

airborne.

In dusty conditions, extraction ventilation and possibly filtration is essential. Dusty air is

likely to be very erosive, and fans and ducts should be designed accordingly and be

properly maintained.

when drilling rock or concrete, dust control measures such as wet drilling, vacuum collectors,

and water mix spray systems must be used to maintain dust levels within limits set for gases,

vapors, fumes, dusts, and mists.



PART TWO



24.6 ILLUMINATION (also see Pt 2 section 7)

24.6.1 general

• General lighting levels should be such that any hazards can readily be seen. Higher lighting

levels should be provided locally, particularly near machinery and in working areas.

• A risk assessment should be carried out to help determine whether or not fixed electric

lighting is required and, in the exceptional case where it is not, hand lamps or cap lamps

should be provided.

• Where potentially explosive atmospheres could exist, all lighting should be

explosion-protected.

• The lighting scheme should be designed to minimize glare. Fluorescent and

incandescent luminaires produce less glare than floodlights.

• Where colour recognition is an important factor, the type of light source should be

carefully considered. For example, sodium lighting can present problems in colour

discrimination.

24.6.2 level of lighting

In a tunnel, the lighting level is subject to the dimensions of the tunnel, the light absorbency of the

surrounding surfaces and also tunnel atmospheric conditions. Light absorption is less in tunnels

that have light-coloured smooth walls than in similar tunnels having dark irregular surfaces.

Lighting levels can be measured with a lightmeter and should be as high as is practicable, taking

into account the work to be undertaken in the area. The table below sets out the recommended

mean lighting levels.

24.6.3 mean lighting levels

Area Lighting level

Walkways 10 lux at walkway level

General working areas 100 lux at working surfaces

Tunnel face

Excavation areas

Crane lifting points

100 lux illuminated from at least two widely separated sources to avoid shadows

The presence of dust or mist in the atmosphere can also have a very significant effect on lighting

levels and should be a consideration to meet the values in the above table.

Regular maintenance, including cleaning, is essential and should therefore be as easily

accessible as possible.



PART TWO



24.6.4 type of lighting

• floodlights - should be located at a suitable height to light areas from above and

should not be directed horizontally. They should be arranged so that their fields

overlap and sited to minimize shadows cast on walkways or workplaces by

obstructions or plant etc.

• temporary fixed lighting - considered for longer-term works.

• portable lighting – used where no other form of lighting exists for pedestrian access

to worksites

• hand lamps or cap lamps – if used it is essential that management procedures be put

in place and facilities provided for their proper storage, charging, distribution, use, and

maintenance.

24.6.5 emergency lighting

• Because tunneling is wholly dependent on artificial light, lighting systems should be

made as secure as possible and should be provided with adequate emergency

resources and power supplies.

• Battery-powered emergency lighting can be used to provide standby lighting. The

capacity of the batteries should be sufficient to maintain the lights for enough time to

allow persons in the area to take appropriate action without danger.

• Emergency lighting should be installed along the tunnels intervals of not more than

50 m to allow safe egress from the tunnel, and should be installed at the following

locations:

� fire and first aid points

� escape routes

� emergency exits

� tunnel access points

� control and communication points

� locations where particular hazards exist

• Alternative mains supplies or standby generation can also be used to provide

emergency lighting. Where the emergency lighting is dependent on an alternative

supply or standby generator supply, the wiring should be adequately protected i.e.

resistance to fire (A), resistance to fire with water (W), and for resistance to fire with

mechanical shock (Z). It should also be protected against mechanical damage.



PART TWO



24.7 ATMOSPHERIC CONDITIONS (see Pt 2 section 21 for further information)

24.7.1 general

• monitor and control atmospheric conditions within pits and tunnels at all times by

qualified staff.

• approved atmospheric monitoring devices to be used whilst labour working in or around

pit tunnel area.

• staff to be trained in the use of atmospheric monitoring devices, device maintenance,

and understanding of gases and other atmospheric conditions that can alter air

conditions.

• quality of air shall be to the following standard :

∗ 21.00% Oxygen

∗ 79.00% Nitrogen (includes 0.94% argon)

∗ 0.03% carbon dioxide

∗ Other gas amount to less than 0.1%

∗ a minimum of 19% oxygen is acceptable for tunnelling

∗ pollutant levels should not exceed their occupational exposure limits and should

be reduced as low as reasonably practicable.

24.7.2 confined spaces

• workforce to be trained in confined space procedures

• emergency rescue B.A. sets to be on hand and personnel trained in use.



PART TWO



24.8 LIFTING EQUIPMENT

24.8.1 general

The cranes most commonly utilized for tunnel access shafts are crawlers,, mobile,

gantry and tower cranes. These are more suitable for shallow rather than for deep

shafts because of the progressive difficulty of control. Special hoists can be required in

deeper shafts (generally considered to be 50 m or deeper).

In the vicinity of any shaft, special precautions should be taken to prepare a suitable base

for siting a crane to minimize settlement and to spread crane loads as widely as possible,

and also to avoid excessive lateral thrust from the ground against the shaft lining. A

reinforced concrete raft, or beams, spanning any sensitive area should be designed

and provided if the ground resistance is locally inadequate.

With mobile cranes that are not restricted to predetermined locations, particular care

should be taken to check that loadings imposed upon the ground are kept within safe

limits, i.e. that they are no greater than the bearing capacity of the ground.

24.8.2 clearances

Where adequate personnel clearance around a crane (500 mm) cannot be provided,

access to areas of restricted clearance should be prohibited while the crane is

operating.

24.8.3 long or difficult loads

When long loads need to be slung vertically because of restricted space, the slinging

arrangements should be devised to prevent the load from slipping. This should be done

by providing properly designed lifting points. The load under suspension should be

balanced and the lifting speed controlled to prevent the load from swinging out of

control. If any difficult loads are to be lifted, the shaft should be cleared of persons other

than any essential to the hoisting operation while the lift is in progress and these

persons should be safely positioned.

24.8.4 special requirements for using hoists underground

Hoists used in underground construction must be equipped with a limit switch to prevent

over travel at the top and bottom of the hoist way.

The limit switch should only be used when operational controls malfunction. Hoist controls

must be arranged so the operator can reach all controls and the emergency power cutoff

without reaching beyond his normal operating position.

Other aspects of hoist safety that apply to underground construction include:

• Employees may not ride on top of any cage, skip, or bucket unless inspecting or

maintaining the system and wearing a safety belt or harness.



PART TWO



• Personnel and materials must be hoisted separately (except small tools and supplies

secured in a non hazardous manner).

See Pt 2 Section19 for more detailed information re safe use of hoists.

24.9 SHAFTS

24.9.1 shaft sinking

general

The shaft sinking operation is likely to have an impact on the general public, and can

affect adjacent structures. Particular care should be taken in designing and locating

shafts to minimize disturbance outside the site. Both safety and environmental factors

should be considered.

shafts under construction

• Where mechanical means of excavation are used, it is essential that measures be

taken to ensure the safety of personnel.

• If grabs are to be used, personnel should be either protected within the shaft, or

removed from the shaft before grabbing commences.

• The number of persons in the shaft bottom area should be kept to a minimum whilst

operations are in progress

• Procedures should be set up to avoid persons being underneath suspended loads

wherever possible.

• In small diameter shafts, particular care should be taken due to the limited scope

for refuge, and persons should be alerted to any loads being sent down.

• All skips used in shafts should have positive fixings so that they cannot tip while

being hoisted. Other potential hazards, such as material falling off the top due to

overfilling, or loose material becoming stuck to the bottom, should be assessed and

minimized.

• Larger shafts are often excavated by a 360° hydraulic excavator working within the

shaft. Measures should be taken to minimize the risk of persons being struck or

trapped by moving plant.

• When handling loads with a crane or hoist, precautions should be taken to ensure

that:

• the load or skip does not swing or twist causing it to strike the lining of the shaft or

other structure;



PART TWO



• the load or skip does not catch a ledge, either in lowering or in hoisting, causing it to

tip over and spill out its contents (whether persons or materials);

• the rope does not become slack when the load is resting on the bottom or on a stage

and catch in some part of the shaft structure, with resultant damage when

tightened.

• All plant regularly transferred down the shaft should be designed for hoisting and be

tested and certificated for such work.

• As a standard procedure in lifting, the load should be lifted a short distance then

stopped, steadied and inspected before hoisting continues.

24.9.2 disused shafts

permanently disused

When a shaft is to be decked over on completion of its use, the decking used should be

specifically designed for that purpose and should be installed for its intended use. If a

void is left, it should be ventilated. Traceable records should be kept of all disused shafts

or access tunnels giving details of the shaft or tunnel, and the method of capping or filling.

temporarily disused

When a shaft is temporarily disused following sinking, it should be securely covered to

prevent unauthorized access, e.g. by children. However, it can be advisable to maintain a

lockable opening in the cover, to enable escape or to allow access for inspection purposes.

The cover should be vented.

tunnel eye

A shaft through which any opening is to be formed should be designed to facilitate the

safe construction and use of that opening.

When a tunnel eye is to be provided near the shaft bottom through which the tunnel or

heading is to be formed, the shaft structure should be supported as for a tunnel

opening.

The actual operation of breaking out should be carried out with the utmost care

because the ground is inevitably disturbed by the sinking of the shaft, and it is probable

that water has followed down the side of the shaft however carefully grouting has been

done. Immediate close support of all ground is therefore often essential.

In bad ground, it can be advisable to fix the first setting of a heading, or build the first

ring of iron or concrete, within the shaft. Alternatively, a small heading can be driven out

of the shaft, from which a break-up for the full size access tunnel is constructed at a safe

distance in undisturbed ground, the heading or tunnel being subsequently enlarged back

to the shaft.



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shaft top layout

The layout and detail at the top of the shaft should be designed to prevent the accidental

fall of persons, plant, spoil or material into the shaft.

The area immediately around each shaft should be level, clear of obstructions and

properly drained; it should generally provide a safe working area, and should be

adequately lit.

Stacking and storage of materials should be arranged at a distance from the shaft top

so that excessive ground pressures are not imposed on the shaft.

The shaft should be guarded using, for example, additional segmental rings or

substantial steelwork and/or solid bariers and mesh, which should reach a height of at

least 1.2 m above adjacent ground level.

Surface water should be excluded from the shaft by the provision of barriers and by

drainage and pumping if necessary. Special precautions should be taken against

inundation.

Mobile plant poses a particular hazard. Either it should be physically prevented from

working near a shaft, or barriers should be erected that are robust enough to prevent the

equipment from falling into the shaft.

personnel access

Personnel access in shafts should be by fixed access equipment such as a mast climbing

hoist or man-riding crane where it is reasonably practicable to provide such equipment

In all cases where the normal means of access is by mechanical means (hoist or crane),

there should be a secondary means of egress to cover plant breakdown.

Fixed access should be provided in every shaft as early as possible, and in any case on

completion, except where an alternative route provides safe pedestrian access to the

base of the shaft.

Fixed access includes stairways, ladderways or vertical ladders with protective hoops.

Stairways should be used whenever possible as the preferred option, as these allow

persons to carry hand tools and similar equipment.

Every ladder should be securely fixed at its base and at the upper landing. It should

extend at least 1.1m above the upper landing unless other adequate handhold is

provided.

Vertical ladders fixed to shaft walls should be made of steel (rather than light alloy or

timber). Vertical ladders should have protective hoops and straps fixed above a height of

2.5 m from a landing.



PART TWO



The foothold at every rung on all ladders should be unobstructed. Landings should be at

intervals not exceeding 9 m. They should be solidly constructed with hand rails, guard

rails and toe boards. Openings for ladders should be as small as is practicable and sited

clear of the foot of the upper ladder. Every landing should be adequately lit.

Stair bays and ladder bays in shafts should be protected by substantial barriers against

swinging loads being handled in the shaft.

All means of access including hoists should be inspected weekly, and maintenance

carried out where necessary.

24.10 SMALL HEADINGS AND SMALL TUNNELS

Because of the very confined space in small tunnels, some hazards are intensified. As

such, projects are often very limited in space, time and resources. It is therefore

essential that those working in such tunnels be made familiar with the hazards, and that

a risk assessment be made to establish appropriate methodology before work

commences.

general

• For tunnels under construction, the internal size for man-entry should be not less

than 1.2 m high by 0.9 m wide, in order to facilitate rescue. Tunnels smaller than

this should be constructed by methods that do not involve man-entry.

• The risk of collapse or excessive settlement is greater with small timbered headings

than with other forms of tunnel construction. Only the highest standards of

workmanship in initial timbering and subsequent back filling should be used.

• Any temporary support should be capable of lasting for as long as the heading

remains open and be capable of securing the surrounding ground against

settlement and collapse.

rescue and escape

• In small tunnels, persons cannot walk upright and can pass one another only with difficulty.

It is normal practice for a single person to excavate the face, although a second should

always be present.

• Arrangements should be defined for the rescue and escape of the face workers in the event

of accident, injury, illness, collapse of the tunnel face, immobilization of a locomotive,

derailment or fire etc.



PART TWO



ventilation

• Ventilation can be a particularly difficult problem. There will be little or no natural circulation, and

shallow tunnels through variable ground will frequently pass through or near ground with

organic content or with other contamination that could pollute the tunnel atmosphere. Where

contamination could occur, a forced ventilation system should be used to limit the ingress of

contaminants, and a supply of fresh air to the face is therefore essential. Low-volume, high-

pressure ventilation systems may be appropriate owing to the lack of space.

pipe jacking

• the high thrusts necessary to propel the pipe forward should be resisted by a properly designed and constructed abutment or thrust wall at the working pit.

• hydraulic rams and any load-spreading rings, spacing blocks or packers should be carefully

secured, with all loaded surfaces precisely aligned perpendicular to the thrust.

• as far as possible, persons should be protected from and withdrawn from the vicinity of

highly stressed equipment during thrusting.

• hydraulic pipes and, in particular, flexible

hoses, should be properly protected from

crushing and impact damage.

• the use of lubricant injected through the

pipes on to the sliding surfaces can assist

in reducing thrusts. If lubricants are

injected at high pressures, eye protection

should be provided.

• when jacking pipes through loose or

water-bearing soils, a slurry machine or

an earth-pressure balance machine

should preferably be used to contain the

face safely

• if using an open shield, precautions

should be taken against a run of loose

material into the face of the shield, which

could lead to the collapse of the overlying

ground.

• when jacking pipes into firm or stiff clays, the techniques adopted should take into account

any displacement of the soil caused by entry of the pipes, and possible heave of the ground

surface.

Typical pipe jacking/tunnelling drive pit



PART TWO



• jacking pipes are installed via a working shaft and joined using hydraulic jacks. It is essential

that all persons seek shelter or protection within the part-completed pipeline or elsewhere

whilst pipes are lowered.

24.11 GROUND SUPPORT

24.11.1 ground support of portal and subsidence areas

Portal openings and access areas must be guarded by shoring, fencing, head walls or

equivalent protection to ensure that employees and equipment have a safe means to

access these areas.

Subsidence areas must be similarly guarded by shoring, filling in, or placing barricades and

warning signs to prevent entry.

Adjacent areas must be scaled or secured to prevent loose soil, rock, or fractured

materials from endangering portal, subsidence, and access areas.

24.11.2 ground support of underground areas

A competent person must inspect the roof, face, and walls of the work areas at the

beginning of each shift and as often as necessary, the ground conditions along all access

ways to ensure safe passage, also any loose ground considered to be hazardous to

employees must be scaled, supported, or taken down.

A competent person must determine how often rock bolts need to be tested to ensure that

they meet the necessary torque, taking into consideration ground conditions, distance from

vibration sources, and the specific bolt system in use. Only torque wrenches should be

used when torsion-dependent bolts are used for ground support.

Employees involved in installing ground support systems must be adequately protected

from the hazards of loose ground.

The bottoms of any support sets installed must have sufficient anchorage to prevent

ground pressures from dislodging the support base.

Lateral bracing (including collar bracing, tie rods, or spreaders) must be provided between

immediately adjacent sets to increase stability.

Any dislodged or damaged ground supports that create a hazardous condition must be

promptly repaired or replaced. The new supports must be installed before removing the

damaged supports. Some type of support, such as a shield, must be used to maintain a

safe travel way for employees working in dead-end areas ahead of any support

replacement operations.

24.11.3 ground support of shafts

Shafts and wells more than 5 feet in depth (1.53 m) entered by employees must be

supported by steel casing, concrete pipe, timber, solid rock, or other suitable material. The

full depth of the shaft must be supported except where it penetrates into solid rock that will



PART TWO



not change as a result of exposure. Where the potential for shear exists, where the shaft

passes through earth into solid rock in either direction, or where the shaft ends in solid

rock, the casing or bracing must extend at least 5 feet (1.53 m) into the solid rock.'

The casing or bracing must also extend 42 (± 3) inches above ground level unless a

standard railing is installed, the adjacent ground slopes away from the shaft collar, and

barriers exist to prevent mobile equipment operating near the shaft from jumping over the

bracing. If these conditions are met, the casing or bracing may be reduced to 12 inches

above ground.

SECTION 25

SECTION 25

FALSEWORK

DEFINITION 1

INTRODUCTION


25.1 MAIN RISKS 2

25.2 STANDARD SOLUTIONS 2

25.3 RESPONSIBILITIES AND PROCEDURES 2

25.4 DESIGN PHASE 4

25.5 ERECTION AND CONSTRUCTION 6

25.6 POINTS OF LOAD TRANSFER 9

25.7 LACING AND BRACING 10

25.8 SPECIAL PRECAUTIONARY MEASURES WITH

PERMANENT FALSEWORK 12

FALSEWORK SAFETY CHECKLIST

(ADM/H&S/CL/2.25/1)


HSE Construction Codes of Practice

PART TWO


ADM/H&S/Pt 2 01 March 2005 FALSEWORK 1 of 12

SECTION 25

FALSEWORK

INTRODUCTION

Since collapses of falsework cause loss of life and serious injuries, the objective of this section is to

ensure that all persons involved with are well informed of safe procedures and of proper application of

these in order to set the risk of failures to minimum.

The check list at the end of this section also includes guidance on related matters in concrete

construction: falsework, steel fixing and concrete operations.

DEFINITION

Falsework is defined as any temporary structure used to support a permanent structure during its

erection and until it becomes self – supporting.

This definition also applies not only to in-situ concrete construction, but also precast concrete

structures, structural steel, steel erection, and even such items as brick arches, etc. indeed, any

construction method where the permanent structure may have a period of instability, requiring support

is the erection process.


Ministerial Order No. (32) Year 1982 - Article 7, 19 & 20



PART TWO



25.1 MAIN RISKS

• people falling during steel fixing and erection of

falsework

• collapse of falsework

• materials falling whilst striking falsework

• manual handling of shutters reinforcing bars etc

• being struck by a concrete skip

• silica dust from scrabbling

operations

• arm and back strain for steel

fixers

• cement burns from wet concrete

25.2 STANDARD SOLUTIONS

Falsework covers a wide range of temporary support methods and BS 5975 recognises that,

in simpler and more commonplace situations, e.g. support of floors and beams involving light

loadings and low height support (within the range of standard props) etc., standard solutions

can most likely be used instead of individual design,

Standard solutions are given in section 8 of BS 5975. However, unless the job falls within the

limitations of the particular standard solution, further design will be required.

With standard solution designs, the set of information released would include the following:

• materials and equipment details to be used in falsework.

• drawings showing dimensional data and ranges of allowable tolerances.

• allowable loadings they can carry.

• necessary limitations such as possible types of foundations.

25.3 RESPONSIBILITIES AND PROCEDURES

In any safe procedure for erecting falsework, the responsibilities for the different phases

should be clearly identified.

These phases are as follows:

• design brief

• concept of the scheme

• design drawings and specifications

• checking of design, specification and control of the following in-situ activities:

∗ erection of falsework on site

∗ monitoring of falsework during permanent structure construction

∗ dismantling and maintenance of falsework



PART TWO



All the above phases and responsibilities have to be co-ordinated, distributed, and overall

checked by the Falsework Co-ordinator whose responsibilities and duties are defined

below:

Falsework Co-ordinator

• co-ordinate all falsework activities;

• ensure that the various responsibilities have been allocated and accepted;

• ensure that a design brief has been established with full consultation, is adequate,

and is in accordance with the actual situation on site;

• ensure that a satisfactory falsework design is carried out;

• ensure that the design is independently checked for:

a) concept

b) structural adequacy

c) compliance with the brief;

• where appropriate, ensure that the design is made available to other interested

parties, e.g. the structural designer;

• register or record the drawings, calculations and other documents relevant to the final

design;

• ensure that those responsible for on-site supervision receive full details of the

design, including any limitations associated with it;

• ensure that checks are made at appropriate stages covering the more critical

factors

• ensure that any proposed changes in materials or construction are checked

against the original design and appropriate action taken;

• ensure that any agreed changes, or corrections of faults, are correctly carried out on

site;

• ensure that, during use, all appropriate maintenance is carried out

• after final check, issue formal permission to load if this check proves satisfactory;

• when it has been confirmed that the permanent structure has attained adequate strength,

issue formal permission to dismantle the falsework.

Of particular note in the above list of duties is the concept of issuing a formal permit to

load before any concreting takes place - followed, at the appropriate time, by a permit

to dismantle.



PART TWO



Whilst contractors will need to make individual decisions as to how the

recommendations of BS 5975 are best implemented, the basic principle - someone

made responsible for ensuring that all parties are adequately informed and co-

ordinated and that all checks have been carried out - is to be unreservedly

recommended.

25.4 DESIGN PHASE

25.4.1 design brief

Whether the falsework design is provided by standard or by individual designs, the

parameters on which the design is to be based need to be clearly established, in this

respect. It must be recognised that the loads imposed on falsework do not only arise from

the permanent structure, many will occur as a result of method and plant decisions.

The design brief should be prepared in both cases of standard and individual solution

design and all design parameters should be precisely determined and stated clearly in the

design brief.

25.4.2 conceptual scheme

At this step, it is decided whether the selected design method for falsework will be of

standard solution type or of individual solution type, basic loading calculations are done and

the type of material to be used for falsework is decided upon.

The basic items to be considered at this stage, but not limited to, are the following:

25.4.2.1 estimation of loads to be supported by Falsework

Not only the weight of the permanent structure, but also other factors are to be included in

the calculation of loads to be applied to falsework

Factors to be accounted for are as follows:

• weight of permanent structure: (this should be based on actual unit weight of materials

used in permanent structure).

recommended values for common types are:

• unit weight of precast concrete units: 2,700 kg/m3.

• unit weight of in-situ concrete: 2,500 kg/m3.

• weights of masonry or brickwork to be obtained from the supplier or calculated by

weighing samples.

• unit weights of structural steel to be obtained for standard sections from the manufacturer’s tables.

• weights for all the attachments and bolts should be included in weight calculation of

steelwork.



PART TWO



loading sequence

To prevent the build-up of stresses in individual members of the support structure, and to

eliminate the possibility of moment reversal and uplift on supports, designer of falsework

must be aware of:

• sequence of pouring

• method of pouring ( continuous or in bays placed on different days)

• type of applied vibration method (external or internal), magnitude of final

permanent deflections in relation to progressive construction above the first supported

member

• method and sequence of designed and specified post-tensioning

Additional loads arising from plant and method of erection are imposed on the

falsework, most common causes being:-

• weight of materials initially stored on falsework

• weight of labour performing work on falsework during erection

causes for arising dynamic loads

• dumping concrete on falsework from

skips

• shock loads resulting from steel or

precast elements

• surge loads reaching to falsework from

concrete pump pipelines

• vibration duration and method

• moving loads like placing plant,

dumpers, and erection cranes

supported on falsework .

• openings in falsework to allow for

below passage of plant and traffic and

others

recommended unit loads values for in-situ concrete casting:

• falsework materials stored on falsework : 50kg/m2

• limited concrete heaps in addition to impact, weights of labour and plant involved in

spreading, compacting and levelling concrete : 150kg/m2

25.4.2.2 modification of loading programme

Any modification of the loading programme after designing falsework should only be carried

out after consultation with of falsework designer. It is the responsibility of the site team to

notify the designer of any changes.

25.4.3 design drawings and specifications

At this stage, final calculations, drawings and specifications, including those related to the

materials prepared and appropriately shown in detail on the drawings.



PART TWO



25.4.4 checking of design and specifications independently

At this stage the falsework co-ordinator ensures that design calculations, drawings and

specifications are checked by an independent designer.

25.5 ERECTION AND CONSTRUCTION

This phase includes all the steps related to the construction of falsework and checking its

proper performance. These steps shall include the following:

25.5.1 distribution of responsibilities and necessary information.

• all persons involved in site erection and supervision of falsework should be made aware

of their responsibilities in this respect.

• to ensure proper performance, all persons in charge for erecting, inspection and checking

activities should receive copies of the following:

∗ all design drawings and specifications

∗ required standard details

∗ check lists, to ensure that all stages are executed properly.

25.5.2 materials and equipment

general

There should be no start in the erection of falsework unless all necessary materials and

equipment are already made available on site, otherwise, assurances that materials and

equipment delivery to site are to be made whenever their incorporation in the structure is

required. Whether new, second hand or fabricated equipment and materials are to be

incorporated into the erection, they should be checked for their compliance with the design.

timber

any timber to be used should comply with the following:

• type, grade, and size in accordance with the drawings and specifications.

• no presence of (defects, shakes, splits, winds, loose or large knots, and crushed or

damaged areas) is allowed.

• no protruding nails or fixings from previous use are allowed.



PART TWO



structural steel

the following items are to be checked:

• correct type of steel is used.

• fabricated sections are in compliance

with dimensions and tolerances shown

on drawings.

• specified web stiffeners are provided.

• quality of materials to be used. If the

material is already used in previous

projects, certified experts are to check

the suitability of the materials for re-use

despite some aspects like holes, welds

and cut-outs that may show on it.

• that provided fixings and fittings are in

compliance with relevant specifications.

scaffolding

the following are main requirements:

• tube materials should be as specified

• straight and no dents

• no excessive pitting

• ends square and free from splits

• fittings undamaged

• threads and nuts should be free from

obstructive materials including rust

• all threads should be undamaged

fabricated equipment

Fabricated equipment should be checked using a semi-visual check. Checking of fabricated

equipment should always be performed with the following applicable restrictions:

• no unofficial repair is to be undertaken before the inspection check is made.

• no substitution for critical items (like high tensile pins in props) is allowed. These items

should be provided as new.

25.5.3 foundations

It is of great importance that foundations of falsework be properly erected and thoroughly

checked.

Foundations are the basis on which the integrity of the structure as a whole depends,

therefore you should ensure that:-

• encountered soil in excavation is similar to that reported in soil report.

• no modifications were made to the latest loading programme followed in the final

falsework design.

• execution of the falsework is in conformance with pertaining drawings and standard

details.

• where serious decision has to be made, the designer is to be involved.



PART TWO



Equally, foundations require protection from the effects of weather so that the ground

conditions as excavated are not altered (see Figs.1 & 2). Failure in this respect may result

in collapse or, at best, settlement.

cohesive soils

Provide surface blinding to prevent ponding of water which alters appreciably the

characteristics of cohesive soil.

cohesionless soils

• provide cut-off drains and surface blinding to prevent the wash-out of non-cohesive soils

due to flowing water, especially in storm conditions.

• when it is recommended by the designer that full bedding of the sole plates be

performed, execution should be undertaken as such:

∗ use lean concrete to fully anchor timbers to ground.

∗ use grout or dry pack to fully anchor steel members into foundations.

Ponded Water

Water penetration or Absorption

Fig.2 - INADEQUATE DRAINING: ( WATER PONDS): Character of cohesive soils change dramatically. Answer: Provide surface blinding.

Flowing water:

Fig.1 - INADEQUATE DRAINAGE: Washout danger in storm conditions. Answer: Provide cut off drains and Blind surface

Wash Out Zone



PART TWO



25.6 POINTS OF LOAD TRANSFERNCE

Defined as those areas in the

falsework structure where:

• loads from the permanent

structure are collected and

transferred to the main vertical

or inclined supports

• where loads from vertical or

inclined supports are resisted

by foundations specially

provided or by parts of the

structure already completed.

(Fig. 3 ) illustrates the

definition.

These are critical points in the structure and both those who design falsework and those who

erect it, must be aware of good practice. (See Check List at end of section).

25.6.1 load transfer areas bearers

Fig. 3

Fig.3 - Showing Points of Load Transference Areas

Bearer must be fixed to prop and joist. Vibration of concrete

will move bearer if unfixed.

Bearer should be secured centrally by nailed wedges. Vibration loosens un-nailed wedges, bearer moves and eccentric loading results

Local Crushing

Loose wedges fall out

Prop or support not plumb

Load Transfer Areas

Permanent Structure

Fig.4 - above showing Load Transfer areas Bearers correctly and securely positioned.

Fig.5 - above showing what can happen when wedges are not secured properly and prop or support is not plumb.



PART TWO



25.6.2 load transfer areas – adjustable jacks

25.7 LACING AND BRACING

Ensure that:

Diagonal as

close as

possible to

node

Secondary Timber

Connecting tube on

every row of

standards

Tube brace

will stabilise

up to 6 jacks.

• all specified members are in place.

• all diagonal Bracing are connected to

the correct lacing by a right angle

structural coupler.

• coupling of bracing and lacing should

be made as close as possible to the

node points (connection of horizontal

and vertical members of falsework

structure).

• the distance between the coupling

points and the node points should not

exceed 15cm.

• couplers and connections are tightened

satisfactorily.

• base and head jacks extended more

than 30 cm every row of jacks is

stabilised at top with a bracing tube at

right angle to the main timber

falsework. (see Fig.7 )

• every 6 jacks of same row are

stabilised by a diagonal bracing tube.

Lateral movement creates eccentricity

and reduction of bearing area in timber.

Fig.6 - showing examples of over extension (exceeding 300mm) of adjustable fork heads or base jacks without bracing which can cause the supporting structure to collapse.

Fig.7 - above showing part elevation as viewed in direction of arrow of jack head bracing.



PART TWO



the following items are to be checked for proper installation of end bearers

• full contact is achieved between end bearers and its underlying ground or plates.

• proper restraint is made to ensure the stability of end bearers in their position.

• spacing between centres of plates is to be conserved as shown on drawings.

25.7.1 jack head bracing

Fig.8 - above showing the correct method of using Jack Head Bracing

“a”

When dimension “a” exceed 300mm.

Every row of jacks is joined at top with

a tube at right angles to the main

timbers – and every 6th jack of every

row is diagonally braced in both

directions. Every 6

th jack in

both directions.

Main Timber



PART TWO



25.8 SPECIAL PRECAUTION MEASURES FOR PERMANENT FALSEWORK

Permanent falsework is employed to permanently support structural element like in-situ

slabs. It is designed to take the load of the supported structural element and its own weight

in addition to other loads arising from wind and normal casting operations.

25.8 1 with pre cast elements

• top and bottom surfaces must be marked properly for identification.

• the lifting system must be arranged in a way to avoid collision and consequential

breaking of pre cast elements.

• lateral supports should be provided before releasing pre cast elements from the sling,

especially in the case of beams with a width to depth ratio exceeding 1 - 3.

25.8.2 with steel panels

• steel panels should be properly positioned in accordance with drawings.

• hand-lines should be fixed to these panels to make handling more convenient and safer,

especially in presence of high wind.

• fixing of the panels is made by studs, bolts, or welding to prevent lateral movement,

excessive deflection and displacements arising from wind action.

25.8.3 with glass reinforced plastics (GRP) panels

• during the cutting and grinding of panels, dust masks, eye protection and suitable

protective clothing should be worn.

• panels can be affected by heat, therefore, heat generating sources should not be brought

close to these panels.

25.8.4 with glass reinforced cement (GRC) panels

• safe handling requires gloves to be worn by involved workers.

• during the cutting of panels, dust masks and eye protection should be worn.

• to ensure stability, panels should be stacked in an organized way.

• when lifting panels by crane, a spreader beam should be used.

Note: Anchoring of decking panels and use of clamps or weights whenever required is a must to

prevent uplift forces from moving the panels.

SAFETY CHECKLIST - FALSEWORK


ADM/H&S/CL/2.25/1 01 March 2005 SAFETY CHECKLIST - FALSEWORK & STEELFIXING 1 of 3

Since errors in falsework erection are not always remediable, checking for the correctness of

falsework erection should be scheduled far enough ahead of erection time for the permanent

structure. Items to be checked for the correctness of falsework erection are the following:

General

�� adequate anchorage, levelling and correct positioning of sole plates and grillages are achieved.

�� base plates and grillages should be located to the centre of underlying sole plates.

�� vertical supports checked.

�� vertical alignment should be plumbed within deviation in accordance with specified tolerance.

�� spacing for these members is to be executed in conformance with drawings and standard

details.

�� all members, couplers, fittings, wedges of the falsework and others are installed properly,

secured, tightened and at correct positions. If these precautions are not taken into account,

loose and non-nailed wedges may fall-out in presence of any vibration arising from activities

such as concrete placing and consolidation.

At points of Load Transfer

�� correct details applied as per fig.3.

�� base and head jacks are not over extended unless detailed with adequate special bracing (see

figs. 4 & 5)

�� that steel section web stiffeners are provided as detailed.

�� there is positional accuracy of all members.

�� there are no eccentricities in excess of allowances specified.

Lacings and Bracings

�� all specified members are in place.

�� all bracings and lacings are coupled as close to node points and never more than 150mm away.

�� all bracings and lacings are connected to correct members e.g. diagonals to lacings to allow

right angle structural couplers to be used.

SAFETY CHECKLIST - FALSEWORK



required precautions during erection and use of falsework

�� during the construction of large items, suspended slabs with proper guarded edges and suitable

access ladders shall be used.

�� no storage should be placed on falsework since it is not designed to carry additional heavy

loads for other purposes.

�� falsework should be designed to allow safe lifting and handling from points designed for this

purpose.

�� persons not involved in the construction process, dismantling or inspection of falsework should

be denied access.

�� loose materials and plant should be fixed against any movement including lateral movement

induced by high winds.

�� whenever it is possible that workers can fall from slab falsework by more than 2metres, suitable

edge guards shall be installed.

�� whenever workers are erecting falsework elements higher than 2 metres over previously

erected slabs, guarded work platforms with access ways should be provided. These access

ways should be also guarded and wide enough to allow for workers to carry materials (see Pt 2

section 29 - Scaffolding & Working Platforms)

�� proprietary falsework systems should be erected and used in accordance with manufacturers’

instructions.

required precautions during dismantling of falsework

�� it must be determined ahead whether back-propping before complete release of the falsework

or re-propping after release of the falsework is the method to be employed.

�� for the safety and convenience of workers carrying out the dismantling activity, proper

temporary platforms must be provided.

�� proper tarpaulins or nets should be placed to decrease the danger of any falling material.

�� all dismantled and removed materials shall be immediately stored and properly handled to allow

for its use in the future.

dismantling steps should be carried out in the following sequence:

�� removal of loose fittings and materials

�� removal of projecting nails and sticking elements (in the case of concrete) as work proceeds.

�� before removal of safety guardrails making part of the falsework, replacement safety guardrails

are to be installed and connected to the edges of concrete.

�� after removal, falsework should be supported safely during repair, oiling and other maintenance

works needed before reuse.

SAFETY CHECKLIST - STEELFIXING



Precautionary measures to be taken with steel fixing include the following:

�� steel bundles should never be carried or lifted by the binding wire. Proper slings should be

used.

�� steel fixers should work at safe places or shops provided on site. Persons not involved in steel

shop work should be denied access.

�� during the cutting of reinforcement, protective gloves and eye protection must be worn by

persons performing work.

�� only recommended types of blades should be fitted to disc cutters to prevent any accident

arising from the breaking of a blade.

�� only trained workers are to be authorized to use the disc cutters.

�� torches shall not be used in cutting steel of types adversely affected by heat.

�� the short end of the cut bar should not be left to fly off and endanger life of persons.

�� projecting steel bars should be capped to reduce their risk potential.

�� proper walkways should be installed over the fixed steel cages to secure the safety of persons

crossing over to access their destination.

PILING

INTRODUCTION 1



26.2 MATERIAL HANDLING 3

26.3 TYPES OF PILING OPERATIONS AND PRECAUTIONS 3

CHECKLIST FOR PILING METHOD STATEMENTS

(ADM/H&S/CL/2.26/1)

SECTION 26

PILING

INTRODUCTION.

Piling operations can give rise to different hazards dependent upon the type of piling being

undertaken. Certain hazards are, however, generally common on all types of piling, and this section

gives both the general precautions to be taken and the special precautions relating to the different

types of piling.










26.1.1 method statement

Piling contractors should be requested to provide an appropriate written method statement. A

general checklist for the production and checking of such method statements is provided at

the end of this section. It is essential that induction training and information specific to the

method statement is provided to piling operatives.

26.1.2 underground services

Prior to piling, all underground services in the area should be located and rendered safe. It is

important to consult the appropriate Utilities for the area on these matters. A check should

also be carried out to ensure that there are no cellars, underground watercourses or ground

conditions, etc., which could create hazards during the operation. (see Pt 2 section 6 for

further information on Underground/Overhead services)

26.1.3 cranes and lifting gear

• cranes must be selected and used in accordance with the requirements of Pt 2 section

19-Cranes and Hoists

• if a rig with a SWL of more than one ton is used for general lifting operations, such as the

loading and transport of materials on site, it must be fitted with an “automatic safe load

indicator” ASLI.

• a firm level base of adequate bearing value must be provided, or crane mats used.

• as there is a risk of the cores of

pendant/bridle ropes fracturing due to shock

loading, these ropes should be opened up

and the cores carefully examined at 3 monthly

intervals.

• any crane used for raising or lowering men

must be fitted with a dead man’s handle and

the descent effectively controlled; the latter is

currently achieved by power lowering.

• properly constructed man carrying cages,

which are unable to spin or tip, must be used.

The cages should be regularly and carefully

inspected. (see Fig.1) Fig.1 - Properly constructed and

tested man riding safety cage

• records of thorough examination must be held for all lifting appliances and gear, which

must be adequate for the job, paying particular attention to the risk of damage to gear by

sharp edges.

• piling machine operators must be at least 18 years of age, trained, competent, medically

fit and authorised by site management to operate the machine.

• cranes which have been employed on piling duties should be subjected to a thorough

examination before being returned to general lifting operations

26.1.4 personal protective equipment (PPE)

• all persons working on piling operations must wear safety helmets (suitable helmets, with

chinstraps and smaller peaks are now available), Ear and eye protection must be

provided and worn where necessary. (see Pt 2 section 12)-PPE.

• when piling from a pontoon or adjacent to water, personnel should wear life lackets.

Rescue equipment (e.g. a safety boat and Iifebuoys with lifelines attached) must be kept

ready for immediate use and enough men must know how to use it. (see Pt 2 section 28)

-Working over or Adjacent to Water.

26.2 MATERIALS HANDLING

• when splitting bundles of sheet piles, chocks should be used. If large quantities of piles

are handled, the use of purpose-made strops and grips is advised.

• piles should not be stacked too high or in a cantilever position. Spacers and chocks

should be used where necessary. Tubular piles should not be stacked more than four

high and should be properly chocked.

• when lifting piles or piling hammers, hand lines should be used to control the load. It is

important that due consideration is given to wind speed during these operations.

26.3 TYPES OF PILING OPERATIONS AND PRECAUTIONS

26.3.1 driven sheet piling

The assessment of risk must consider the following simple factors in connection with the

sheet piling process:

• how the piles are held in position during driving,

• how the piles are to be threaded,

• how the first pile is secured whilst the second is threaded,

• the overall scheme to devise a system to prevent the falls of persons and materials.

Piles can either be held in position during driving using a special leader arrangement

attached to the crane or piling plant or, alternatively, a gate system may be used as

described below.

26.3.2 gate systems

A supporting system should be chosen which is appropriate for the operation, e.g. where

short runs of sheet piling are required and accuracy is not the main criteria, then a single

gate system may be used.

A single gate system is made up of a simple frame of either timber or steel gates supported

by blocks a suitable distance above ground level. A shallow guide trench is normally dug to

assist with the location of the sheet piles.

“Gate support system” See Fig.2 shown above is a two gate system, made up from timber

H-frames, set in concrete Kelly Blocks. These H-frames are then spanned by RSJ’s (gates).

If the gates are over 2m high, or over any potentially dangerous area, they must not be used

as working platforms unless fitted with toe boards which rise at least 150mm, and main

guardrails at least 910mm above the walkway. Additionally, intermediate guardrails, or other

rigid barriers must be fitted so that there is not an unprotected gap of more than 470mm in

height in the means of protection against a fall (as in the illustrated in Fig.2).

Where such protection cannot be provided, access to slinging points must be gained by

ladder and NOT by means of the gates.

Sheet Piles pitched – not driven

Sheet piles pitched and part driven

Hanger Brackets

Tirfor Tension

Anchor Block with lifting eye cast into block

Guardrails Toeboard

Walkway top gates with gap covered

Bottom Gate

Wooden Wedges

Bolts

Kelly Block

Fig.2 - TWO GATE SYSTEM – Showing piling, the use of hanger brackets and the provision of a safety walkway

• permanent ladder access must be secure and extend above the gates sufficiently to

provide a safe handhold. (A distance of 1 .05m is recommended).

• when constructing Kelly Blocks, reinforcement should be placed in the concrete base.

Vertical RSJ’s should have a good “key”. Vertical timber should not be cast into the block

but should be wedged and bolted.

• where doubt exists over the stability of Kelly Blocks, guy lines should be used.

• lifting eyes should be cast into the blocks.

26.3.3 pitching piles

• if shackle holes have to be burned in the pile, sharp burrs should be removed to prevent

damage to shackle pins.

• remote release shackles (see Pt 2 section 30)- Erection of Structures , should be used

where possible and the sheet pile must not be lifted vertically without first checking that

the pin is properly engaged through the sheet. The length of the operating rope must be

less than the length of the pile, and the rope should be secured around the pile to prevent

snagging or being caught in the wind and becoming inaccessible.

• if piles are too heavy for a remote release shackle and work cannot safely be carried out

from a ladder, a lifting cage should be provided to gain access for unscrewing the

shackle. (see Fig.1)

• if a special lifting eye is to be welded to the pile for angled pitching, the weld should have

a factor of safety of at least 2.

• long sheet piles should be pitched with a pile threader following the manufacturer’s

guidance for use. Where this is not possible, a pile pitching cage should be used. The

cage should hang from an adjacent pile with the operatives wearing safety harnesses

hooked to the adjacent pile before the crane hook is removed from the cage.

• when sheet piles are being pitched, it is essential to take particular care to ensure the

stability of the first few piles, but especially the first pile. This may be achieved by fixing

the pile to the gate at two points so that it cannot move within the plane of the gate. This

action will also ensure that the pile is stable if an effective toe-in is not achieved due to

hard/stony ground conditions.

• when feeding sheet piles through top and bottom gates, use wood blocks or a bent bar.

Never use a straight pinch bar, as fingers can easily be trapped.

When working off ladders during pitching piles operation, the following additional precautions

is required:-

clutching

• ladder must be placed in the valley of a previously placed pile; the ladder must be footed

and, when at the top of the ladder and both hands are required For clutching, a safety

harness must be worn and secured to the pile using a girder grip. (see Pt 2 section 29) -

Scaffolding/Working Platforms.

wedging

• ladder must be placed against the RSJ and footed; wedges should be pre-positioned on

the RSJ a 41b lump hammer should be used as this can be swung with one hand. If two

hands are required, a safety harness must be worn, with the lanyard wrapped around the

RSJ or connected to a girder grip.

• work method must not be changed without the approval of the senior site representative

or the contractor responsible for the piling operation.

• if windy conditions make the handling of the sheet piles difficult, work must stop until the

responsible person has been consulted and a safe method of continuing the work has

been devised.

26.3.4 hammers

• hammers, and in particular all clamping bolts, should be inspected daily.

• use guide rope when positioning a hammer.

• stand clear when starting and operating.

• ALL personnel should be at ground level during piling operations.

• should the piston of a hammer jam, the trip-lever should be pulled to the open position

before removing the hammer from the pile.

• damaged high pressure airlines or high voltage cables, feeding the hammer, can present

a serious hazard to persons working in the vicinity of the operation. Therefore it is

important to keep supply lines/cables under constant observation to avoid damage by

trapping or from sharp objects.

double acting air hammers

• all hose couplings should be properly manufactured and matched. The joining of rubber

pipes to brass spigots should be by clamp and not hose clips.

• ensure that the oil bottle/filter lid is secure.

internal drop hammers

• always place a swivel between the hammer and hoist rope.

• attachment of a hoist rope should always be done using a properly matched anchor and

pear; the dead end of the rope should be secured using a bulldog clip or other approved

means.

• intermediate linking shackle pins should be secured.

• check hoist ropes daily during operations.

26.3.5 helmets and inserts

Pile helmets or crowns must be well constructed, strong enough and free from defect.

Should packing or spacers be needed, they should be drilled, tapped and screwed to secure

in place, and then welded.

Remember that any welds to a solid cast helmet will eventually crack.

26.3.6 pile extraction

• where pile extraction is necessary, due allowance should

be made for the frictional forces occurring between the

pile and ground, in order to determine the correct size of

crane and extractor. (see Fig.3)

• it is good practice to use a tag line between hook and

adjacent pile to prevent the extractor swinging out of

control should the pile snap.

• care should be taken when lowering extracted piles to

ensure that the load on the crane hook is kept vertical.

26.3.7 bored piling

• spoil from boreholes should be kept clear of access to the borehole which, after

completion, should be fitted with a cover or other suitable protection. As an alternative to

a cover, it is common practice to back fill or to leave the auger in the borehole.

• persons are not permitted to enter any borehole less than 750 mm in diameter.

• where it is necessary for any person to enter a borehole, special precautions must be

taken. It must be ensured that no toxic or flammable substance/gas is present in the

borehole and that the air is fit to breathe. Where necessary, a proper ventilation system or

suitable breathing apparatus must be provided. No person should remain in the hole for

more than one hour at a time.

Fig.3 - Showing typical quick release type of pile extractor

accessing pile shaft

Descent by any person into any pile shaft, or bore hole, from here on referred to as a shaft,

should only be carried out in compliance with the following conditions:-

(see Fig.4)

• shaft must be lined with a steel sleeve from

ground level.

• top of the capsule used by the person to

descend the shaft must never descend lower

than one metre above the bottom of the

shaft support sleeve.

• capsule must be totally enclosed, with

windows to enable the person carried in it to

see the unsupported section below the

support sleeve, or the excavated under

reamed section at the base of the shaft.

• under no circumstances should the

person leave the capsule whilst it is

below the supported section of the shaft.

• capsule must have fresh air and

telecommunication supplies from ground

level at all times whilst it is below ground.

• metal steps must be provided inside the

capsule from the bottom to the top.

• top of the capsule must have opening flaps

to enable the person to be rescued in the

event of the capsule being trapped below

ground.

• crane used to raise and lower the capsule

must have powered lowering which is in

correct working order.

• capsule must have low voltage lighting

inside it.

• an appropriate gas monitor must be kept in

the capsule at all times whilst it is below

ground.

Steel Sleeve

Minimum one metre

Communication line and nominal 20mm diameter steel air supply pipe with diffuser to reduce noise

Step irons for emergency escape

Capsule doors with windows

Floor doors opening upwards

Clay Level

Fig.4. - Showing Access to Shaft and Boreholes and illustrating some of the points listed above.

• all operatives having to descend a pile shaft in a capsule, must be given adequate

instruction and training on procedures to be followed, and the risks involved.

• it is preferable for mechanical means to be provided and used for inspection and

sampling the sides of the shafts, instead of having to send a person down to carry out the

work.

• banks man must be in attendance at all times when any person is lowered into a bore

hole. He should be in such a position that he can observe the man in the borehole, and If

necessary, should wear a safety harness and line.

• operatives engaged in this work should be trained and competent in rescue from deep

bore holes.

• emergency rescue drills supervised by a competent person should be carried out at the

start of operations and at regular intervals thereafter. A set of printed rescue drill

instructions should be issued and displayed at each site.

• all rescue equipment should be tested regularly to ensure that it is in good working order

and capable of reaching to the maximum depth of the borehole.

• supervisors should be trained in methods of gas detection, respiratory resuscitation, first

aid and the use and maintenance of breathing apparatus.

26.3.8 piling augers

• all machinery should be in good condition and no

lifting apparatus should be used unless there are in

existence current records of test and thorough

examination. (see Fig.5)

• all control levers on the piling rig should be clearly

marked to indicate their purpose and mode of

operation.

• persons must stand well clear of the auger both

when drilling and when discharging spoil.

• if the secondary rope is used as a crane (i.e. to lift

casings into place) then there must be an approved

automatic safe load indicator fitted to the system.

• when ropes are subject to heavy wear, they must be frequently inspected and changed as

necessary.

Fig.5 - Type of Piling Auger commonly used on Building/Construction Sites.

26.3.9 tripods

(see Fig.6)

• no tripod should be used unless the rig is tested and the legs marked. The numbers on

the items must coincide with the numbers on the test and examination records

• ropes should be secured with suitable Fastenings, e.g. bulldog clips.

• where appropriate, properly constructed saddles or hard eyes should be used.

Note: knots must not be tied in any rope used for lifting.

• base plates should be adequate and secured to

prevent any accidental movement of the rig.

• tripod legs must not be overspread or overloaded.

• only the correct pins should be used in the

sheerlegs.

• the safe working load must be clearly marked on

the winch, and records kept of test and thorough

examination.

• all parts of the winch should be effectively guarded.

• constant attention must be paid to the condition of

rope, which should be changed as soon as it

becomes necessary.

• when a rope/chain block is being used to extract the casings, the capacity of the block

must not exceed the capacity of the rig.

• under no circumstances must there be less than 2 full turns of the rope on the winch

drum at any time

Fig.6 - Showing a typical type of Tripod used for Bore Piling.

SAFETY CHECKLIST - PILING OPERATIONS


ADM/H&S/CL/2.26/1 01 March 2005 SAFETY CHECKLIST - PILING OPERATIONS 1 of 1

CHECKLIST FOR PILING METHOD STATEMENTS

Piling method statements should normally include the following so far as is relevant in the

circumstances:

�� Name and address of the piling contractor.


�� Names of the supervisor/foreman and appointed safety adviser and arrangements for


�� Descriptions of the work to be carried out including the number, type and size of piles and the

method of placing.

�� Duration of the work.

�� Hours of work.

�� Nature of the soil including details of any contamination present and the precautions to be

taken.

�� Details of the methods of locating and avoiding any existing underground services, whether or

not their presence if known.

�� Details of the personnel to be used and their training/ experience.

�� Assessment of any work at height and arrangements for the provision of a safe place of work

and safe access/ egress.

�� Details of plant and equipment to be used together with confirmation that all necessary records

will be provided on site.

�� Details of auger cleaning device used and auger or drill guarding provided.

�� Confirmation that man access will not be permitted to under reamed pile shafts.

�� Assessment of exposure of operatives to noise and the precautions to be taken.

�� Assessment of environmental noise and the steps to minimise disturbance.

�� Details of the PPE to be provided to personnel.

�� Arrangements for protecting openings.

�� Arrangements for the storage / stockpiling of materials.

Note



SAFETY CHECKLIST - PILING OPERATIONS


ADM/H&S/CL/2.26/1 01 March 2005 SAFETY CHECKLIST - PILING OPERATIONS 2 of 1

SECTION 27

SECTION 27

WELDING

INTRODUCTION 1


27.1 GAS WELDING -GENERAL 2

27.2 STORAGE OF GAS CYLINDERS 2

27.3 CYLINDER HANDLING 3

27.4 CYLINDER ATTACHMENTS 4


27.6 OPERATIONAL FAULTS 6

27.7 ELECTRIC ARC WELDING 8

27.8 HAZARDS ASSOCIATED WITH WELDING 9



PART TWO


ADM/H&S/Pt 2 01 March 2005 WELDING 1 of 11

SECTION 27 WELDING

INTRODUCTION

Welding has been defined as the fusion of two pieces of metal, rendered plastic or liquid by heat or

by pressure, or by both.

There are many different welding processes, but the two most commonly used in the construction

industry are gas welding and electric arc welding.

In gas welding metal fusion is achieved by the use of very high temperature flames, produced by a

mixture of gases at a torch or blowpipe. The gases involved are oxygen and a fuel gas, such as

acetylene or liquefied petroleum gas (LPG).

In electric arc welding, the arc is struck between an electrode and the workpieces. The temperature

attained by the welding arc is approximately 4000 degrees celcius. At this temperature, the work

pieces are melted and fused together.


Ministerial Order No. (32) Year 1982 - Articles (5)d & Articles 7 - 9



PART TWO



27.1 GAS WELDING -GENERAL

27.1.1 cylinder identification

Oxygen cylinders are painted black and the outlet valve threads are right-hand. The outlet

valve threads on fuel cylinders are left-hand. Acetylene cylinders are painted maroon and

propane, the most commonly used LPG is red.

Valve connections are not therefore interchangeable, and every effort should be made to

preserve the original colour to avoid confusion.

27.1.2 gas characteristics

Oxygen has no smell, is not itself flammable, but readily supports combustion. Too much

oxygen in the atmosphere (greater than 25 per cent) can be extremely dangerous. If the

gas impregnates materials. e.g. clothing, which normally will only burn slowly, they are

liable to burst into flames.

Acetylene is lighter than air, has a wide flammable range and will form an explosive

mixture with air or oxygen.

LPG is heavier than air and may therefore collect in low lying areas.

27.2 STORAGE OF GAS CYLINDERS

27.2.1 cylinders (general)

• vertically stacked cylinders, whether full or empty, should be secured against falling.

• full cylinders should be kept separate from empty ones.

• cylinders should be shielded from direct sunlight, or other heat, to avoid the build up of

excess internal pressure which might lead to gas leakage or, in extreme cases, bursting

of the cylinder.

27.2.2 oxygen cylinders

• should be stored at least 3m away from those containing acetylene or LPG, since any

mixture of oxygen with one of the fuel gases which might result from a leakage, could

be highly explosive.

• must not be kept in the same storeroom as LPG or acetylene cylinders.

• may be stacked horizontally, maximum four high, and wedged to prevent rolling.

• gas cylinders should preferably be kept on a hard standing in a safe place in the open

air. Where this is not reasonably practicable, flammable gases should be kept in a

storeroom, constructed of non-combustible material, and has adequate high and low

level ventilation.



PART TWO



27.2.3 acetylene and LPG cylinders

Whether full or empty, should always be stored and used in the upright position. If they are

allowed to lie horizontally, acetone or LPG liquid will be withdrawn from the cylinders where

the gas and safety devices such as bursting discs, temperature sensitive fusible plugs and

relief valves will be rendered ineffective

27.3 CYLINDER HANDLING

• hands and clothing should

be free from grit, grease

and oil when cylinders are

handled to prevent them

from slipping and to

prevent grit from getting

into the valve, or grease

on to the nozzle or valve.

• every effort should be made to stop

nozzles being used for handling

purposes. They are not designed to

take such weight or stress.

• cylinders in use should normally be

kept and moved in purpose built

trolleys. If it is necessary to move

cylinders which are not in a trolley,

regulators and hoses should be

detached and a check should be

made that valves are properly shut.

Under no circumstances should

cylinders be rolled along the

ground.

• if cylinders are to be lifted by crane, they should be secured in a special carrier. On no

account should they be lifted with chain or wire rope slings, which can easily

slip.

• gas cylinders must be treated with care and not subjected to shocks or falls.

• when they are transported in a vehicle around a site, they should be secured to prevent

injury in the event of any sudden vehicle movement, and when being unloaded from a

vehicle, they should not be dropped to the ground.

Hose Check (Non Return Valve)

Container for Valve Key

Flash Back Arrestor

Outlet Pressure Gauge

Cylinder Contents Gauge

Pressure Regulating Screw

Valve

Fire Extinguisher

Fig.1 - Example of Purpose Built Trolley (Note fitments for the torch, a dry powder Extinguisher and a Cylinder Valve Key).



PART TWO



• acetylene cylinders must always he transported and used in the vertical position. If they

have been left in the horizontal position, they must be stood upright for approximately

10 minutes to settle out before use.(see Fig.1)

27.4 CYLINDER ATTACHMENTS

27.4.1 regulators

• regulators must always be fitted to the cylinders

to reduce the gas pressure from that in the

cylinder to the working pressure of the blowpipe.

• only regulators designed for the gas being used

and rated for the current full cylinder pressure,

should be fitted to the cylinders.

• regulators are fitted with filters, but too much dust

can easily clog them. To prevent this from

happening, the cylinder valve should be "cracked

open" before the regulator is fitted to the cylinder.

This will blow all dust and other foreign matter

clear.

• the adjusting screw of the regulator must always be released before the cylinder valve

is opened, and the cylinder valve must be opened gradually. If it is opened suddenly,

the abrupt compression of the gas will generate excessive heat which might be enough

to ignite the valve seat material or damage the gauge.

• periodic checks should be made to ensure that no gas is leaking from the regulator

when the pressure regulating screw is set at zero. A leak will cause a build-up of

pressure in the hose to the torch when the blowpipe valve is shut. Checks for gas

leakage from any part of the equipment should only be made with water containing

detergent. Bubbles in the detergent indicate the presence of a leak. (see Fig. 2)

27.4.2 hoses

hoses should be:-

• kept for one type of gas only, and colour coded for identification - red for acetylene or

other fuel gases (except LPG), orange for LPG and blue for oxygen.

• inspected daily before use to see that they are free from cuts, scratches, cracks, burnt

or worn patches.

• be effectively clipped or crimped to the equipment and protected at all times from sharp

edges, falling metal, passing traffic and sparks from the welding operation.

Fig. 2 - Example of a Type of Regulator used for Welding Purposes



PART TWO



27.4.3 non-return valves and flashback arrestors

If oxygen and fuel gas become

mixed in one of the hoses, a mixed

gas explosion or “flashback” may

occur. To avoid the risk of igniting

such an explosive mixture, each

hose should be purged with its own

gas before the blowpipe is lit. This

operation should be carried out in a

well ventilated space away from any

source of ignition.

To prevent gas mixtures arising in

use, e.g. if the blowpipe nozzle

becomes blocked, non-return valves

should be fitted to each blowpipe

inlet connection. The additional use

of flashback arrestors (flame

arrestors) is strongly recommended.

In situations of high risk, flashback

arrestors must be fitted. (see Fig.3)

Examples of such situations

include:

• in a confined space where

access is difficult or the means of

escape may be endangered by

fire/explosion.

• operations under hot work permit

adjacent to live operating plant.

• near compressed air workings.

• when operatives are under

training.

• where there is a device in the gas line with significant internal volume, e.g. a welding

flux container.

27.4.4 blowpipes

If the nozzle of a blowpipe becomes damaged or blocked, then a build up of pressure can

cause a reverse flow of gas and a flashback may occur. It is advisable, therefore, that

blowpipes should be dismantled and cleaned at regular intervals.

Fig. 3 - DIAGRAM OF A FLASH BACK ARRESTOR “A” Indicator Button (in normal operation a green safety

band shows around the button. After a flashback the band does not show and the outer shroud must be lifted).

“B” Pressure Sensitive Cut-Off Valve (In the event of a flashback, the pressure wave will activate the valve to cut off the gas supply automatically).

“C” Thermal Cut off Device (Designed to cut off gas in the event of extreme temperature such as a hose fire. The unit is activated at 950 C).

“D” SINTERED METAL FLAME ARRESTING ELEMENT (Extensive surface area designed to arrest a flashback flame quickly. The element surface area is important to ensure long service life to permit high gas flow in normal operation).

“E” NON-RETURN VALVE (Upstream of the flame arresting element, this unit ensures no gas can backfeed and ignite incoming gases.



PART TWO




• only proprietary fittings should be used on gas welding equipment. If a cylinder valve

leaks and cannot be tightened with a spanner, the valve should be closed and the

cylinder returned to the supplier with a label indicating the fault. Cylinder valves should

never be packed with washers.

• on no account should oil, grease or other substances such as soap be allowed to come

into contact with an oxygen regulator valve or fittings, as these substances are

explosive in the presence of high pressure oxygen. Any leaking oxygen fittings should

not be tightened before closing the cylinder valve and venting the oxygen to

atmospheric pressure.

• it is dangerous to allow the flame to come into contact with the cylinders, or a lighted

torch to be hung on a regulator or its guard. It is equally dangerous to rest blowpipes on

empty oil drums or similar containers even after the flame has been extinguished. It has

been estimated that only half a fluid ounce of flammable material may he required to

give sufficient vapour to form an explosive mixture in a 40 gallon drum. Such a small

volume of liquid would be present as only a thin film inside the drum.

• fatal and other serious accidents are caused by oxygen enrichment of the atmosphere,

due to leaks from equipment or the deliberate "sweetening" of the atmosphere with

oxygen. In such circumstances, the area must be purged with fresh air until the oxygen

level is below 25 percent. All clothing should be well ventilated in the open air to prevent

the risk of spontaneous combustion. At the same time, all sources of ignition in the area

must be eliminated.

27.6 OPERATIONAL FAULTS

It is not unusual for operational faults such as minor explosions to occur during welding or

cutting operations. Some are more frightening than harmful; others can lead to very

dangerous conditions.

Types of explosions and other faults, descriptions, causes, preventative and corrective

actions are shown in the following table:-



PART TWO



Operational

Faults

Description Cause Preventative

Action

Corrective Action

Explosions

Flame snap

out

Unintentional

extinction of the

flame outside

the nozzle

orifice.

• Both regulators at incorrect presure.

• Torch nozzle obstructed

• Nozzle held too close to the work.

• Blowpipe valves not opened enough to

allow adequate gas

flow.

• Completely shut down both torch valves.

• Check regulator settings. • Check nozzles. • Re-light - ensuring adequate gas flow

Sustained

back fire

Retrogression of

the flame into

the blowpipe

neck or body,

the flame

remaining alight.

• regulators not set to

correct pressure,

• nozzle obstructed,

• nozzle overheated.

• close both blowpipe valves, oxygen first.

• check cylinder pressures, • check and adjust regulator settings,

• cool torch and check, • clean nozzle orifice of any obstruction,

• re-light after purging both hoses.

Backfire • Retrogression of the flame

towards the

blowpipe

mixer,

• flame being either

extinguished

or re-ignited

at the nozzle.

• regulators not set to correct pressure.

• light applied before flow of gas mixture

properly established.

• Check correct

pressure on both

regulators. • Ensure blowpipe

valves are

sufficiently

opened. • Never hold

nozzle too close

to o the work

• close both blowpipe valves, oxygen first.

• check cylinder pressure, • check and adjust regulator setting,

• check torch, • re-light when gas flow is properly established.

Flashback Usually one of

the hoses will

have burst and

possibly ignited

• Mixing of gasses occurs when the

hoses have been

disconnected from

blowpipes and/or

regulators.

• Ensure all connections are

tight.

• Ensure all cylinder valves are open and

blowpipe valves

closed.

• Purge each hose seperately and

consecutively by

opening blowpipe

valve and allowing

gas to flow for

sufficient time to

ensure only pure

gas remains in

hoses.

• Close the valve for each gas as the

exercise is

complete.

This exercise should

only be carried out in

the open air or well

ventilated areas,

• Close both blow pipe valves.

• Close both cylinder valves. • Extinguish hose if alight. • Remove acetylene regulator, if “bull nose” is

sooty, suspect a dangerous

condition and carry out

procedure advised under

heated cylinder. • If “bull nose” clean, replace regulator, repair hose(s) or

obtain new ones. • Check whether cut off valve has closed: reset or replace

as necessary. • Re-assemble equipment,

hoses and continue with

work.



PART TWO



Operational

Faults

Description Cause Preventative

Action

Corrective Action

Heated Cylinder

Cylinder will show

signs of heat, paint

will start peeling off

and a white heat

spot will become

apparent outside

cylinder.

Where an acetylene

cylinder becomes

accidentally heated

or gets hot due to

internal

decomposition,

Ensuring that cylinders

are always kept clear

of direct heat and

sunlight.

• Rraise the alarm and

ensure the Civil

Defence is called,

• Rmove any external

source of heat, if

possible,

• Close cylinder valves, if

possible.

• Evacuate the area,

• Liaise with the Civil

Defence on arrival.

• Arrange for the

suppliers to remove the

cylinder.

27.7 ELECTRIC ARC WELDING

The current used for electric arc welding may be either direct or alternating but, whichever

system is used, it is important that the voltage be as low as is consistent with efficient

welding.

On building sites, arc welding is usually carried out with direct current (DC) supplied from a

diesel driven mobile generators. A welding lead takes the current from the generator to the

electrode holder. A welding return, usually, but incorrectly termed the "earth" carries the

return current from the work piece being welded back to the generator.

27.7.1 cables and cable couplings

Welding leads and welding return cables are frequently dragged over rough surfaces. Their

insulation should, therefore, be suitable for resisting hard wear and should be examined

frequently for defects, The part of the cable which is connected to the electrode holder

should be as flexible as possible so as not to hamper the movement of the welder. The

welding return should be of a section not less than that of the welding lead.

Joints between cable sections should be made with properly constructed insulated cable

couplings adequately shrouded, so that live metal is not exposed if the parts of the

connector are separated.

The welding return should be firmly connected to the metal on which welding is taking

place, by means of a well constructed clamp.



PART TWO



27.7.2 electrode holders . (see Fig.4)

An electrode holder is essentially a pair of

spring loaded jaws, or a threaded sleeve

fitted to the end of the welding lead. The

holder should be fully

insulated, so that the live portions cannot he

touched accidentally

27.8 HAZARDS ASSOCIATED WITH WELDING

The principal hazards associated with gas welding are fires, explosions, burns, eye

damage, heat stress, respiratory disease and systemic poisoning. Additional hazards

which may result from arc welding are electric shock, ultra violet radiation and ozone.

27.8.1 fire and explosion

The potential for fires and explosions is always present unless gas cylinders are stored

and handled correctly. When any type of welding equipment is in use, the naked fame. or

arc, provides a source of ignition for any combustible material, flammable gas or vapour.

Where possible, flammable materials should he kept out of any area where welding is

taking place. Where such a course of action is not practicable, fire resisting sheets should

be used to protect the surroundings from the flame and from spatter. At least one fire

extinguisher should always be immediately available in the area of any welding operation.

27.8.2 burns

Skin burns may result from metal spatter or from

touching hot workpieces. The hands, arms, legs,

and feet are particularly vulnerable, so should be

protected by gloves or gauntlets.(see Fig.5) and

spats and jackets made from chrome leather. The

use of leather safety footwear is also

recommended.

Prolonged exposure to the heat from welding may

lead to reddening of the skin of the face. In the

case of gas welding, discomfort may be avoided by

the use of a hand shield.

Fig. 4 - Example of fully insulated Electrode Holders

Fig.5 - Example of Welders Leather Gloves.



PART TWO



27.8.3 eye damage

During any welding operation, the eyes may be penetrated by sparks, spatter, slag and

other foreign bodies. During gas welding infra-red and of course visible light is emitted, but

not ultra-violet light. lnfra-red may dry the outer surface of the eye which may become

irritated.

Eyes must be protected from infra-red and visible light

by means of box goggles with a housing made to BS

1542, and filters made to BS EN 169 and 170.

Ultra-violet (UV) radiation, to which the eyes are very

sensitive, is produced during arc welding. The effect

of UV radiation on the eyes may vary from

conjunctivitis to possible permanent damage to the

retina.

In order to avoid these injuries, welders must use a

welding helmet or hand screen, with housing

complying with BS 1542, and fitted with appropriate

filters to BS EN 169 and 170. (see Fig.6)

Further guidance on eye protection is given in (See Pt 2 section 12) PPE.

27.8.4 protection for others

Persons working in the vicinity of arc

welding also need protection from UV

radiation. This protection can be given by

means of screens placed around the

welders working area. (see Fig.7)

27.8.5 heat stress

The longer the duration of welding, the hotter the surroundings, including the welder

become. This heat stress is intensified the smaller the confines in which the welding

operation is taking place. In extreme cases the welder may faint.

If thermal stress is envisaged, then ventilation should be introduced and consideration

should be given to having a second person on standby in case of emergencies.

Fig.6 - Welders Helmet complying with B.S. 1542 & B.S. EN 169/170

Fig. 7 - Example of a see through portable type welding screen.



PART TWO



27.8.6 respiratory disease

Before carrying out welding operations, the materials involved should be identified, the

risks assessed and necessary control measures established.

Every welding process produces gas and fumes which may result in respiratory disease as

the hot metal vapour from the weld pool will produce fumes when the vapour is rapidly

cooled and oxidised by the surrounding air. Fumes consist mainly of a cloud of line

particles, predominantly iron oxide.

In addition to fumes, harmful gases may also be generated during gas welding, the

principal toxic gases produced being carbon monoxide and nitrous fumes which is only

formed in large enough amounts to be dangerous when combustion is incomplete.

Arc welding produces ozone, a gas which irritates the respiratory system. Nitrous fumes

are also produced, but to a smaller extent than during gas welding.

It cannot be assumed that natural ventilation will produce acceptably low gas and fume

concentrations in the welder’s breathing zone. If a number of welding operations are being

carried out in the same area, or the work is being carried out in a confined space, then the

risk is obviously increased.

The most effective form of fume control

equipment is the type which allows the

extractor hood to be placed as close to the weld

as possible. Ideally, the extracted fume-laden

air should be effectively filtered or exhausted

into the atmosphere and not allowed to enter

the air of the workplace. If fume control is

suspected of being inadequate, the air in the

breathing zone of the welder must be sampled

to determine its suitability for breathing. (see

Fig.8)

27.8.7 systemic poisoning

The fumes from galvanised metals, lead coated or other toxic metals may affect not only

the respiratory system, but also the rest of the body, particularly where the work which

produces the fumes is carried on for any length of time in poorly ventilated conditions.

The provision of an exhaust ventilation system for this type of work is essential and, in

addition, the use of respirators may be required.

Air sampling must be carried out to confirm the adequacy of the precautions.

Fig.8 - Example of a portable fume extractor.

SECTION 28

SECTION 28

WORKING OVER OR ADJACENT TO WATER

INTRODUCTION 1


28.1 PLATFORMS, GANGWAYS, ETC. 2

28.2 LADDERS 2

28.3 SAFETY NETS AND SAFETY HARNESSES 2

28.4 SITE TIDINESS 3

28.5 ILLUMINATION 3

28.6 WEATHER CONDITIONS 3

28.7 PROTECTIVE CLOTHING AND EQUIPMENT 3

28.8 FIRST AID 4

28.9 BUOYANCY AIDS 5

28.10 MEANS OF ACCESS: WATER TRANSPORT 5

28.11 RESCUE EQUIPMENT 6


ADM/H&S/Pt 2 01 March 2005 WORKING OVER OR ADJACENT TO WATER 1 of 7



PART TWO

SECTION 28

WORKING OVER OR ADJACENT TO WATER

INTRODUCTION

Any workplace over, on, or near water, presents a danger that persons might slip, fall or be swept off

their feet by a rapid rise of tide, strong current, or swell from passing water traffic. Whether or not a

person is injured by a fall, there is an immediate risk of drowning and/or being carried away by the

current.

Considerable effort must be made, firstly to prevent persons from tripping, falling or being swept into

the water and secondly, if the worst does happen, to ensure that they are rescued in the shortest time

possible before they can come to any further harm.


Ministerial Order No. 32 (year 1982) Article 7





PART TWO

28.1 PLATFORMS, GANGWAYS, ETC.

• platforms and gangways must be a minimum of 4 boards wide complete with guard rails

and toeboards.

• at all edges from which a person might fall into the water, secure barriers or fences are

required.

• warning notices must be erected at all edges and boundaries near water and set so that

they are easily seen by operatives approaching the danger point.

• where platforms or gangways are erected above tidal water, decking boards should be

secured so that they cannot become dislodged by rising water or high winds.

• the provision of additional handholds is always advisable as a precaution in the event of

high winds.

• barges, pontoons etc. used as working platforms, must be properly constructed and

sufficiently stable to avoid tipping.

For further information and guidance on scaffolds and working platforms –

(see Pt 2 section 29) Scaffolds and Working Platforms.

28.2 LADDERS

• must be sound and of sufficient length and strength.

• securely lashed to prevent slipping.

• where ladders are permanently fitted to plant over water, they should be fitted with safety

hoops.

For further information and guidance on ladders – (see Pt 2 section 29) - Scaffolding,

Working Platforms, Ladders and Safety Nets.

28.3 SAFETY NETS AND SAFETY HARNESSES

• safety nets should be properly secured and slung sufficiently far above high water level

for anyone caught in them to remain clear and so that free access of rescue craft is

always possible.

• manufacturers should be consulted on what type of net best suits the kind of work to be

carried out and the prevailing conditions.

• Safety belts or harnesses must be used where appropriate.

For further information and guidance on safety nets – (see Pt 2 section 29) - Scaffolding

and Working Platforms.





PART TWO

28.4 SITE TIDINESS

• tools, ropes and other materials not in use should be stored away and all rubbish cleared

up promptly.

• materials awaiting use should be stacked compactly and, particularly on pontoons, not

piled too high.

• slippery surfaces are extremely dangerous and should be treated immediately.

• oily or greasy surfaces should be gritted or treated with industrial salt or sand.

• drip trays should be sand filled and set beneath all machinery to prevent the development

of oily, slippery surfaces and, especially on pontoons to minimise fire hazards.

28.5 ILLUMINATION

• essential for night work, especially in shafts, dark corners and stairways.

• should have an even spread of light to avoid deceptive shadows and glare.

• area floodlit should always include the immediate water surface.

• spotlights on swivels, should be fixed at strategic points to assist in locating a person in

the water.

• Navigation lights may be needed on working places afloat or sighted close to the shore.

28.6 WEATHER CONDITIONS

Local weather conditions should be obtained and publicised at the beginning of each days

work or shift. Hot weather, rain, rising winds, fog, sea mist etc. are all potential dangers.

28.7 PROTECTIVE CLOTHING AND EQUIPMENT

Protective clothing and equipment, suitable for the work involved, must be provided and

worn.

For further information and guidance on PPE – (see Pt 2 section 12) – PPE.





PART TWO

28.8 FIRST AID

A first aider, trained in Cardiac Pulmonary Resucitation (CPR) and familiar with both rescue

and treatment of drowning, must always be readily available on all contracts involving

working adjacent to, or on water.

The ideal person to be trained to this standard would be the person in charge of the rescue

boat.

The following are the main points to consider when rescuing a person from drowning:-

• choose the safest way to rescue the

casualty. If possible, stay on land and reach

with your hand, or stick or throw a rope or

float.

• when bringing the casualty out of the water,

carry him with his head lower than his chest,

to minimise the dangers of vomiting.

• swim to the casualty and tow him only if you

are a trained life saver, or if the casualty is

unconscious. It is safer to wade, if you can,

than swim.

• treat for drowning and the possible effects of

cold.

• take or send the casualty to hospital, even if

he seems to have recovered well.

minimum contents required in a first aid box:

NUMBER OF EMPLOYEES

1-5 6-10 11-50 51-100 101-500

GUIDANCE CARD (multi language)

1

1

1

1

1

WRAPPED STERILE ADHESIVE DRESSINGS

10

20

40

40

40

STERILE EYE PADS

1

2

4

6

8

TRIANGULAR BANDAGES

1

2

4

6

8

STERILE COVERING FOR SERIOUS WOUNDS

1

2

4

6

8

SAFETY PINS

6

6

12

12

12

MEDIUM SIZE STERILE UNMEDICATED DRESSINGS

1

2

4

6

10

LARGE STERILE UNMEDICATED DRESSINGS

1

2

4

6

10

EXTRA LARGE STERILE UNMEDICATED DRESSINGS

1

2

4

6

10

STERILE WATER OR SALINE IN

300 ML.DISPOSABLES

1

1

3

6

6





PART TWO

28.9 BUOYANCY AIDS

Some form of buoyancy aid must be worn as standard

practice. (see Fig.1) A wide range of life jackets is

available. They should be suitable for the work and the

hazard, conform to BS 3595 or equivalent standard,

and in addition should:-

• provide sufficient freedom of movement for persons

required to wear and work in them.

• have sufficient buoyancy to bring persons to the

surface and keep them afloat, face up.

• be easily secured to the body.

• be readily visible.

• be capable of withstanding hard treatment.

• require minimum maintenance (inflatable types need frequent checking).

• not to be prone to snagging under water.

• have clip- on, self igniting lights.

28.10 MEANS OF ACCESS: WATER TRANSPORT

Where working places are situated on water, and access is only possible by passenger

carrying boats, these crafts are subject to the Abu Dhabi Ministry of Communication and

Coast Guard regulations main requirements of which are:-

• all passenger carrying crafts, prior to use, must be registered with the above

establishments.

• must have their registration renewed annually.

• are only allowed to operate within a stipulated number of passengers according to size.

• provided with the appropriate life - saving and fire fighting appliances as specified by the

regulatory department e.g.

� approved life jackets

� lifebuoy(s) with buoyant heavy line

attached

� v.h.f. radio if craft longer than 35ft.

� distress flares

� first aid box

� dry powder or foam type

extinguisher(s)

Fig.1 - Example of an Adult Buoyancy Aid conforming to B.S. 3595 ( 50 Newtons)

(5kgs. or 11lbs).





PART TWO

28.11 RESCUE EQUIPMENT

28.11.1 lifebuoys and rescue lines

• lifebuoys which are normally 765mm outside diameter

should be fitted with a 30m buoyant life line, knotted at

every 3m to assist handhold. (see Fig.2)

• life lines should be long enough for the state of the tide,

height of working place above water, or for the person

being carried downstream by a current.

• lifebuoys may be constructed of either cork or canvas

covering, or of polyurethane foam with a rigid PVC cover.

• if night work is carried out, approved self ignition type

lights should be used.

• daily checks to be made to ensure that lifebuoys and

rescue lines are in their proper place and in serviceable

condition.

grab lines/throw lines

• to be attached to the working place, or at

other places downstream to give person

something to grab in an emergency.

• should be long enough to allow for the

normal rise and fall in tide.

• should be of the buoyant type with a

marker float at the free end.

• trailing ends to be avoided so that there

is no risk of boats being fouled.

• daily checks to be made to ensure that

they are still in position and that their

condition is sound. (see Figs. 3 & 4)

Fig.2 - Lifebuoy Station complete with Life Lines.

Fig.3 - Throw Line with Buoyancy Bag

Fig. 4 - Throw Lines with Buoyancy Capsules.





PART TWO

28.11.2 rescue boat

• should be properly made and of sufficient

length to afford reasonable stability.

• where conditions merit, inflatable craft are

recommended since they provide a better

chance of getting a person aboard without

injury.

• for work in tidal or fast flowing river water, a power

driven craft is essential equipped with a fixed self

starting device on the motor. (see Fig. 5)

• engines of powered craft, when not patrolling,

should be run several times a day to ensure full

efficiency.

• all rescue boats should carry three oars or paddles to cater for losing one overboard.

• rawlocks should be removable and on retaining lines so that they can hang from the side

without being lost.

• should be fitted with grab lines and carry at least one approved lifebuoy.

• two way communication between boat and shore is always advisable.

• if night work is to take place, a powerful spotlight should be fitted.

• should be manned continuously and on patrol whilst work is in progress by experienced

boatmen trained in basic first aid.

• if possible, there should be two persons to a boat so that one is free to to attend to the

person in the water.

• all first aid equipment on board should have waterproof protection.

28.11.3 rescue procedure

It is essential that:

• the number of persons at work is periodically checked to ensure that no one is missing

• operatives work in pairs so that there is always one to raise the alarm.

• each person is trained in what to do in the event of an emergency.

rescue procedure should consist of

• a set routine for raising the alarm.

• a set drill to provide rescue facilities.

Fig.5 - Typical example of a type of rescue Boat used for rescue purposes, when men are working adjacent to or over water.





PART TWO

• a set routine to for getting persons to hospital whether for check-up through immersion in

water, or for treatment as the result of an injury.

SECTION 29

SECTION 29

SCAFFOLDING - LADDERS - CRADLES - SAFETY NETS

INTRODUCTION 1


29.1 PROVISION OF SCAFFOLDS, ETC. 2

29.2 SUPERVISION OF WORK AND INSPECTION OF MATERIAL 2

29.3 CARE AND MAINTENANCE OF SCAFFOLDING 2

29.4 RUBBISH CHUTES

3

29.5 DISMANTLING

3

29.6 CONSTRUCTION AND MATERIAL 4

29.7 LADDERS USED IN SCAFFOLDS 6

29.8 LAYOUT OF A FULL INDEPENDENT SCAFFOLD 8

29.9 STABILITY OF SCAFFOLDS 9

29.10 WALKWAYS, GUARD RAILS AND TOE BOARDS 10

29.11 SCAFFOLD TOWERS 12

29.12 THROUGH AND REVEAL TIES FOR INDEPENDENT SCAFFOLDS 14

29.13 TRUSS-OUT SCAFFOLDS 15

29.14 CANTILEVER SCAFFOLDS 16

29.15 BIRDCAGE SCAFFOLDS 17

29.16 SUSPENDED SCAFFOLD (NOT POWER OPERATED) 20

29.17 SLUNG SCAFFOLDS 21

29.18 SUSPENDED ACCESS EQUIPMENT 22

29.19 SUSPENDED SAFETY CHAIR (BOSUN’S CHAIR) 26

29.20 SAFETY NETS 27

29.21 MOBILE ELEVATING WORK PLATFORMS 30



PART TWO


ADM/H&S/Pt 2 01 March 2005 SCAFFOLDING - LADDERS - CRADLES - SAFETY NETS 1 of 33

SECTION 29

SCAFFOLDING - LADDERS - CRADLES - SAFETY NETS

INTRODUCTION

Since work on many construction sites is required to be done at heights which cannot be reached from

the ground, means must be provided to prevent persons from falling from their place of work and

injuring themselves; precautions must also be taken to prevent falls of tools and materials.

In most case it will be practicable to provide a safe working platform supported by some form of

scaffold or, failing this, by using a suspended scaffold or mobile work platform.

Where it is not practicable to provide a working platform, or where provisions of such a platform would

be unreasonable because of the nature or short duration of the work, personal suspension equipment

must be provided and used. As a last resort, where none of these measures are practicable or

reasonable in the circumstances, injury from falls must be prevented by the provision and use of

safety nets or safety harnesses.

This section is therefore designed to give standards, and where applicable, guidance on the provision

and use of the above.

It covers the standard types of scaffold structures and ladder access, together with standards and

guidance on mobile work platforms and use of safety nets.


Ministerial Order No. (32) Year 1982 Article (19) B.



PART TWO



29.1 PROVISION OF SCAFFOLDS, ETC.

Where work cannot be safely done from the ground or from part of a building or other

permanent structure, there shall be provided, placed and kept in position for use, properly

maintained either scaffolds, or where appropriate, ladders or other means of support, all of

which shall be sufficient and suitable for the purpose.

Where a scaffold, or part of a scaffold is to be used by or on behalf of an employer other

than the employer for whose workmen it was first erected, the first mentioned employer

shall, before such use:

• take express steps, either personally or by a competent agent, satisfy himself that the

scaffold or part there of is stable,

• that the materials used in its construction are sound, and that the standards as laid down

in this manual are in adhered to.

29.2 SUPERVISION OF WORK AND INSPECTION OF MATERIAL

• no scaffold shall be erected or be substantially added to, altered or dismantled except

under the immediate supervision of a competent scaffolder possessing adequate

experience of such works.

• a competent person shall inspect all materials for any scaffold on each occasion before

being taken into use. Contractors shall appoint such competent persons and shall

arrange for their training as necessary.

29.3 CARE AND MAINTENANCE OF SCAFFOLDING

• the maintenance of all scaffolding materials is clearly very important. While they are not

in use, the materials should be properly stored.

• when tubes are supplied with a protective coating, care should be taken to protect the

coating so that the tubes do not deteriorate excessively.

• unprotected steel should not be used where the atmosphere is particularly corrosive.

Tubes which appear to be excessively corroded should be examined by a specialist

before they are used.

• tube straightening should only be carried out by specialists as there is a tendency

for work hardening and consequent brittleness to occur during bending and

straightening operations.

• split or damaged sections of tube should be cut out and discarded, all cuts being at

right angles to the tube axis.



PART TWO



• couplers and fittings should be examined before use. Moving parts should be free

from wear or damage and be well lubricated. Particular attention should be paid to

threads.

• scaffold boards should be inspected after each job and any showing signs of abuse,

decay or excessive warping should be discarded. End hoops, or bands, should be

replaced or re-fixed as necessary.

• where boards have split ends which do not exceed the limits specified in BS 2482,

nail plates may be used. No other repairs should be carried out and boards should not

be painted or treated in any way which could conceal defects.

• boards should be cleaned on return from site, then stacked flat, and raised from the

ground on cross battens.

• damaged boards are hazardous and therefore all forms of abuse must be avoided. Do not

use them as a base on which to stack materials, or as ramps at kerbs, or as temporary

roadways. Scaffold boards should not be used as makeshift crawling boards or for

shuttering or propping up door frames.

• boards or other components should never be dropped or thrown down from a height. The

impact resulting from this form of abuse may result in unseen but potentially lethal

damage.

29.4 RUBBISH CHUTES

Rubbish chutes are frequently attached to scaffolds and erected by scaffolding

contractors. It is essential that the design of a scaffold take account of the additional

loads which may be imposed in the normal use of a rubbish chute, by the additional wind

loading and by further loads in the event of a blockage. Further guidance on the

installation and use of rubbish chutes is given in (see Pt 2 Section 33) - Refurbishment

29.5 DISMANTLING

Normal procedure is to dismantle in the reverse order of erection - last up, first down, at

least in the case of more complicated scaffolds, get the same team that put it up to take it

down

• all dismantling activities should be carried out progressively, reversing the erection

process. Therefore scaffolders should work along the elevation removing the

guardrail(s) and then lowering the boards from that section to the lift below. Scaffolders



PART TWO



MUST NOT remove the guardrail(s) from the whole elevation before lowering the

boards.

• it may be necessary to insert additional ties and in any case no ties or braces should be

removed in advance of general dismantling.

• checks should be carried out as to the stability of the structure, and platforms should be

cleared of all materials and debris before dismantling begins.

• once a scaffold is partly dismantled, all possible access to the dismantled sections

should be barred and a warning sign prominently displayed.

• all materials must be lowered carefully; surplus boards and fittings must be removed

from the platforms as the work progresses and, particularly, at the end of each day.

• tube fittings should be stacked at ground level unless the first lift has been specially

designed to support the extra loading.

• the public must be protected at all times. If necessary, barriers should be erected round

the area where scaffolding is being dismantled.

29.6 CONSTRUCTION AND MATERIAL

29.6.1 general

• every scaffold and every part thereof shall be of good construction, suitable and sound

material and of adequate strength for the purpose for which it is used satisfying

recognised international standards.

• sufficient material shall be provided for, and shall be used in the construction of scaffolds.

• scaffold construction should take into consideration the type of work, load, height, and

also weather conditions.

• timber used for scaffold shall be of suitable quality, be in good condition and have the

bark completely stripped off.

• timber used for scaffolds, trestles, ladders and folding stepladders shall not be so painted

or treated that defects cannot be easily seen.

• metal parts used for scaffolds shall be of good quality, be in good condition and free from

corrosion or other patent defect likely to affect their strength.

• no defective material or defective part shall be used for a scaffold.

• all material and parts of scaffolds shall, when not in use, be kept in good condition and

kept apart from any materials or parts unsuitable for scaffolds.



PART TWO



• every scaffold shall be properly maintained/kept clean and every part shall be kept so

fixed, secured, or placed in position as to prevent, so far as is reasonably practicable,

accidental displacement.

29.6.2 partly erected or dismantled scaffolds

No scaffold or part of a scaffold shall be partly

erected or dismantled and remain in such a

condition that it is capable of being used unless

the scaffold complies with the following:

• a prominent warning notice indicating that

the scaffold, or any part thereof is not to be

used, positioned at or near any point of

access; (see Fig.1)

or,

• access to the scaffold or any part thereof is,

as far as is reasonably practicable, effectively

blocked off.

29.6.3 standards and uprights

Should be vertical and spaced

closely enough for the intended

use of the scaffold.

base plates and timber sole

plates

Must be used to distribute the load

from the standard/upright over a

wider area, as well as to offset

possible local subsidence. (see

Fig.2)

29.6.4 ledgers and transoms

• ledgers must be level and fixed to standards with right - angle couplers.

• In normal use, transoms should be spaced so that the spans of scaffold boards should

not be greater than:

∗ 32mm boards: 1.0m



Fig.2 - Showing Timber Sole Plates and Base plates

Fig.1 - Partly erected scaffold correctly signed and blocked off



PART TWO



• transoms must be firmly fixed to ledgers or standards and be so spaced according to the

expected load and thickness of the boards to be used on the platform. (see Fig.3)

29.7 LADDERS USED IN SCAFFOLDS

29.7.1 used as uprights

• to be strong enough for the load

• equally supported on each stile

• secured to prevent slipping

Note: Ladders are only to be used to support a scaffold platform when the work is light e.g.

painting.

29.7.2 provided for access

• top be supported by the stiles resting on a firm, even base.

• stiles should be securely lashed or;

• stairs must be kept free from all obstructions - materials and rubbish, and if they become

slippery, should be cleaned or sanded as quickly as possible

• fixed with a ladder clamp to the ledger or transom near the top to prevent slipping both

sideways and outwards

Fig.3 - LEDGERS: Centres not to exceed 2.0 m,

but base lift may be a maximum of 2.7 m

TRANSOMS: Maximum spacing 1.5 m.



PART TWO



• set at a working angle of 75o to the

horizontal, i.e. one foot out for every four

foot of height, and extend at least 1.05m (5

rungs) above platform level to provide

adequate handhold at all stepping-off points.

(see Fig.4)

• rungs on a stepping-off points should be on

a level with the working platform.

• ladders required to rise more than 9m of

vertical height should have an intermediate

landing place provided.

• stairs must be provided with hand rails, and

where persons can fall more than 2m. There

must be guard-rails fitted at a height of 910

mm to 1.15 m above the centre of each step,

and a lower guard rail fitted since toe-boards

cannot be fitted.

Note: ladders should be either removed or boarded to prevent unauthorised access after

working hours.

Fig.4 - This ladder is securely tied to prevent slipping. It is correctly angled (one out for every four up) and extends above the working platform to allow people to get on and off safely.



PART TWO



6

Fig. 5.

No.1 GIN WHEEL – To be secured on load bearing couplers S.W.L. Clearly marked. load not to exceed 50 KGS.

No.2 GUARD RAIL – Minimum height of 910mm on all structures over 2.00m high and secured on inside of standards. A second lower guard rail or higher toe board should be provided to limit gap to 470mm.

No.3 TOE BOARDS - Min. height 150mm fixed on all structures.

No.4 BOARDING - To be close boarded and end butted throughout.

No.5 TRANSOMS – Maximun spacing 1.5m.

No.6 TARPAULINS – To be fixed only to structures designed for their use.

No.7 STANDARDS. – Centres dependent upon duty use.

No 8 LEDGERS – Centres not to exceed 2m, but base lift may be up to 2.7m max.

No.9 TIES – Hook, Lip, physical reveal etc. to be considered individually, and B.S. requirements observed.

No.10 LEDGER JOINTS – Not more than 1/3 into a bay and be staggered throughout i.e. adjacent bays or lifts.

No.11 STANDARD JOINTS – Must not occur at same height.

No.12 STANDARD/LEDGERS – Fixed with right angle couplers.

No.13 BRACING – Ledger, Zig Zag, Dog Leg, always secured on load bearing couplers at alternate pairs of standards. Face, Façade, Longitudinal, Wind, 45o Angle over full structure height at 30m centres secured with load bearing couplers and joined end with sleeves.

No.14 BASEPLATES – Generally below standards, and 150mm x 150mm size.

No.15 SOLE PLATES – Use in prescribed circumstances and no smaller than 1,000cm2 beneath one standard.

6

29.8 LAYOUT OF A FULL INDEPENDENT SCAFFOLD



PART TWO



29.9 STABILITY OF SCAFFOLDS

Every scaffold shall:-

• be securely supported or suspended

• be rigidly connected to the building or structure

• where necessary, be sufficiently and properly strutted or braced to prevent collapse

(see Fig.6)

• be securely tied, or otherwise supported.

Standards can be prevented from sinking into soft ground by base plates positioned on boards.

Eyebolts fixed into the structure can provide a secure tie – they are particularly useful when there are no openings. They are also useful when window opening cannot be left open for security reasons.

Through ties – ties which pass through openings in the structure and are connected to an inner tube supported within the structure – provide a

secure tie.

Viewed from inside

Reveal ties only provides a reliable support when a reveal pin with a threaded wedge is wound securely into position.

Fig. 6 - Showing the requirement for reveal ties – through ties – fixing of eyebolts and position of base plates in order to ensure stability of scaffold.



PART TWO



29.10 WALKWAYS, GUARD RAILS AND TOE BOARDS

29.10.1 walkways

Every board or plank forming part of working platform, gangway or run shall be:-

• strong enough for the intended work and not be less than

200mm wide if 50mm thick or less, and not less than 150mm

wide if more than 50mm thick.

• board ends must not overlap their supports by more than

four times the thickness of the boards, unless they have

been secured against tipping. (see Fig.7)

• tripping hazards must be minimised by the fitting of bevelled

pieces wherever, of necessity, boards overlap or have

become uneven must rest firmly on their supports, unless

strong enough to have no excessive sag when supported

only by two.

29.10.2 width of walkways

Width of working platforms more than 2m high, must be:-

• 600mm wide (3 boards) when used for persons only and not for materials.

• 800mm wide (4 boards) when used for persons and for the deposit of materials, though

there must be a 430mm passage left for persons clear of materials. This passage must

be increased to 600mm if barrows are to be used.

• 1.05m wide (5 boards) if used to carry a trestle or any other higher platform, and 1.30m

wide (6 boards) if used by masons.

Note: 430mm wide (2 boards) platforms are, however permitted on ladders scaffolds, folding

trestles scaffolds in the vicinity of a roof and suspended scaffolds, when work is light

and of short duration.

29.10.3 toe boards and guard rails

• guard rails and toe boards are

required at the outside of and ends of

all working platforms from which men

and materials can fall more than 2m.

(see Fig.8)

• toe boards and guards rails must be

fitted on the inside of standards to

prevent outward movement.

Fig.7

• the distance between the top of the toe

board and the underside of the guardrail

must not be more than 765mm.

• where materials need to be stored,

additional boards may be necessary to

stop materials falling, or it may be

advisable to suspend wire mesh frames

from guardrail to toeboard to effect

complete closure. (see Fig.9)

Fig.7 - Board ends to overlap their supports by not more than 3 times board thickness



PART TWO



• toe boards must rise at least 150mm above the working platform.

• guard rails must not be less than 910mm, nor more than 1.15mm above the working

platform.

• if guard rails and toe boards are removed to permit passage of men and materials, they

must be replaced as soon as possible afterwards.910mm, nor more than 1.15mm above

the working platform.

29.10.4 moving the working platform

Careful attention must be given to moving all boards from lift to lift, otherwise a well-

designed and prepared deck progressively becomes an incomplete and unsafe platform.

29.10.5 landing places

Landing places should be provided at each 9m of height and be fitted with both toe boards

and guard rails. All openings through which ladders and staircases pass should be as small

as possible and should not exceed 500mm in width.

Fig.8 - Remember: Protection is also required at edges of excavations and where people can fall into water.

Fig. 9 – Brickguards should be positioned so they are prevented from moving

outwards by the toe board.



PART TWO



29.11 SCAFFOLD TOWERS

Tower scaffolds are normally used by painters and others who need to work from a

lightweight structure that can be easily moved from place to place. When mounted on

wheels, they are known as mobile towers.

Towers may be made from normal tubes or fittings, but are frequently constructed from

proprietary components.

The following general standards apply to both types :

29.11.1 foundation

• erected and used on firm ground.

• static towers should have metal base plates.

• mobile towers must be used only on hard, level surfaces and fitted with wheels or castors

which should not be less than 125 mm in diameter.

• castors or wheels should be locked into the base of standards and be fitted with brakes

which cannot accidentally be released.

29.11.2 stability

Manufacturers recommendations will specify either the maximum height to which a tower

should be erected, or the maximum height to least base ratio for free standing towers. In

each case, the height of a tower is that to platform level.

For all towers, recommendations for maximum height to least base ratio are normally:-

Internal towers: 3.5-1 External towers: 3-1

Stabilisers, with pad feet or outriggers with castors, may be used to increase the effective

base size as illustrated in Fig.10.

Towers should be positioned to make the effective least base dimension as large as

possible.

29.11.3 working platforms

• fully boarded and at least 600mm wide, or at least 800mm wide when used for the

deposit of materials.

• protected from tipping or sliding by being properly supported by the use of cleats or other

proprietary fittings.

• any trap door or hatch on the platform should be closed when the platform is in use.



PART TWO



29.11.4 guard rails and toe boards

• fitted on all four sides of the platform.

• Toe boards must rise at least 150mm above

platform level

• guardrails must be between 910mm and 1.15m

above platform with the distance between top of

the toe board and guardrail not exceeding

765mm.

29.11.5 access

Access should be provided either by:-

• vertical ladders attached internally to the

narrow side.

• internal inclined ladders, or inclined stairway,

• ladder sections, integral with frame members

should be climbed from the inside as illustrated

in Fig.10.

• rungs should be no more than

300mm apart and the stiles not

more than 480mm apart

• climbing using the horizontal of

end frames should not be

permitted

• the maximum recommended free-

standing height for mobile towers

is 9.6m, and for static towers, 12m.

29.11.6 precautions during use

• ladder or trestle must never be placed on the top platform to extend the height of the

tower as this will cause instability.

• mobile towers should have their casters turned outwards to provide maximum base

dimension and brakes locked “on” when tower is in use.

• mobile towers should be moved only by pulling or pushing at the base.

• working platform should be clear of persons and materials before towers are moved.

29.11.7 information from suppliers/manufacturers

Manufacturers, suppliers and hirers should provide adequate instructions for their erection,

which must always be available to, and followed by users.

Fig. 10 - Prefabricated tower fitted with an internal ladder, fully boarded working platform complete with guard rails and toe boards, fitted with outriggers to assist stability and lockable wheels.



PART TWO



29.12 THROUGH AND REVEAL TIES FOR INDEPENDENT SCAFFOLDS

Means of resisting both inwards and outwards movement of a scaffold is normally achieved

with ties to the facade at a number of points. Whatever type of tie is used, it should be

established that the strength of the building structure is adequate to sustain loads which will

be transferred to it.

The following types of ties are commonly used, depending on anticipated loading and the

nature of the facade.

through tie

A tie assembly through a window or

other opening in wall. Safe working

capacity 6.25 KN. (see Fig.11)

reveal tie

The assembly of a reveal tube with wedges or screwed fitting and timber pads, fixed

between opposing faces of an opening in a wall, together with a tie tube. Safe working

capacity (where relying solely on friction) 3.5KN inwards and outwards. Where the reveal

tube is tight behind a load- bearing feature, and there is a butt tube, the safe working

capacity is 6.5KN outwards. (see Fig.12)

Secured Packing

Ledger Bracing

Tie fixed with right angle coupler and placed close to the window reveal

Right Angle Couplers only to be used

Ledger Bracing

Tie should be attached to the reveal tube within 150 mm of the end opposite to the reveal pin, whether latter is in the vertical or horizontal position

Fig.11 - Showing main safety requirements when fixing through ties.

Fig. 12 – Showing the main safety requirements when fixing reveal ties.



PART TWO



29.13 TRUSS-OUT SCAFFOLDS

A truss-out scaffold is an independent tied scaffold, constructed in accordance with the

recommendations of BS 5973, projecting from the face of a building or structure. The

supporting structure is known as a truss-out. (see Fig.13)

These scaffolds are generally used where it is impractical, or inadvisable, to build up

from ground level as, for example, for repairs to a parapet wall, or for work on upper

storeys in a tall building on a busy street.

They are entirely dependent upon the building for support.

Therefore:

1) the building itself should be examined to ensure that it is sound enough to take the

stresses involved in anchoring the scaffold and that all ledges and window sills, etc.

are strong enough to bear the load from the rakers,

2) only trained and experienced scaffolders should be permitted to erect truss-out

scaffolds.

Only steel tubes and fittings should be used and these must be specially checked before

use.

29.13.1 structure

• in the very simplest form of truss-out scaffold,

horizontal tubes (needles, protruding through

windows or similar openings), are anchored

within the building to vertical tubes securely

strutted between the ceiling and floor and

bearing hard against the inside wall.

• ledgers are connected with right-angle

couplers to the underside of the needle tubes

to form the base for the working platform.

• the outer ends are supported by rakers bearing

upon the outside wall and a short, vertical tube

is fixed between the foot of the raker and the

inner end of the needle. A ledger is fitted within

the junction of the raker and vertical tube to

which both are connected. Bracing is then

connected as illustrated.

• transoms are then connected to support

boards and a short upright fitted, with a right-angle coupler to the outer end of

transom or needle tube to accommodate toeboard and guardrail.

Fig. 13 – Typical truss out independent tied scaffold



PART TWO



• these simple truss-outs are only intended for very light work and should certainly not be

loaded with materials.

29.14 CANTILEVER SCAFFOLDS

A Cantilever Scaffold is an independent

tied scaffold constructed in accordance with

BS 5973 but erected on beams cantilevering

out from a building.

• The scaffold should be specially designed

and generally takes the form illustrated in

Fig.14

• The strength of the structure of the building

should be checked to ensure that the

loads applied by the scaffold can be safely

resisted.

• The strictest control should be exercised

by the user on the loads transferred from

cantilever scaffolds. There should be full

liaison between the designer and user on

this matter and the drawings and

calculations should state the load limitation

clearly.

29.15 BIRDCAGE SCAFFOLDS

Birdcage scaffolds are normally used for interior work in larger buildings like factories, public

halls, cinemas or churches to provide access to ceilings, walls or soffits for light work, such

as painting, plastering and decorating. They have a single working platform. (see Fig.15)

29.15.1 base

• The floor of the building has to carry the full load of the scaffold and the total weight

involved should be distributed as widely as possible.

• Floors must be examined before the scaffold is begun and if there is any doubt as to

whether they are capable of bearing the weight, they should be shored.

• Soleplates, to support the baseplates of standards, are not merely necessary to

distribute the load; they also help to avoid needless damage to flooring.

Fig. 14 – Typical cantilever scaffold



PART TWO



• Soleplates should always be set at right

angles to beams or joists.

29.15.2 standards

• Standards on baseplates should be set

vertically in rows at not more than 2.50m

centre to centre in each direction.

• Any joints that become necessary in

standards should occur near ledgers and

should be staggered, i.e. joints in adjacent

standards should not occur in the same lift.

• With birdcage scaffolds the floor of the

building has to carry the full weight of the

scaffold and its load Soleplates are therefore

necessary to help distribute the load as widely

as possible - and they should always be set at

right angles to beams or joists.

29.15.3 ledgers

• Ledgers, strengthening and keeping the standards in each row equidistant, should be

fixed horizontally to the standards with right angle couplers.

• The first lift should not be more than 2.50m high; subsequent lifts should be at 2m

intervals.

• Joints in ledgers should be staggered (i.e. joints in adjacent ledgers should not occur in

the same bay) and should preferably be made with sleeve couplers. Joints should be

positioned at not more than one third of the distance between two standards.

29.15.4 transoms

• On all lifts except the top, transoms should be set horizontally and fixed to standards

with right angle couplers.

• At working platform level, transoms spaced at not more than 1.50m intervals (assuming

38mm thick boards are used) should be fixed to ledgers with right angle or putlog

couplers. In each bay one transom should not be more than 300mm from the standard.

Intermediate transoms may be removed if not supporting boards, but those next to

standards should be left in place and fixed with right angle couplers.

• Where transoms need to be doubled to allow boards to butt, they should be spaced so

that no board overhangs by more than four times its thickness or by less than 50mm.

• In larger Birdcage Scaffolds transoms may frequently need to have joints in them. Joints

should preferably be made with sleeve couplers and all joints should be staggered.

Fig. 15 – Typical birdcage scaffold



PART TWO



29.15.5 bracing

• A single lift birdcage is not automatically stable because of its small height. It needs

bracing just as much as a multi lift scaffold. This is normally catered for by the use of

diagonal bracing and, where the birdcage is subject to wind forces, bracing should be

provided with one brace for every six verticals in each line, with the corner panels of

each section being tied in both directions. Bottom connections of the brace must be

attached to the bottoms of the standards by swivels or to a foot tie with right angle

couplers. Foot ties should be provided at a minimum of alternative bays in each

direction.

• For multi-lift birdcages the bracing may take the form of a diagonal tube from top to

bottom, or short tubes between lifts in a zig-zag, or all of one slope in every sixth bay.

29.15.6 tying

• Where the birdcage scaffold is within or against an existing structure, it is often more

satisfactory to use the structure to afford stability. The most satisfactory detail is to

extend the transoms or ledgers to butt the walls, or push/pull fixings may be used. No

vertical should be more than 6 tubes away from a restraint point and at least one should

be provided for every 40m2 of vertical face.

• A mixture of bracing and tying may be used but both directions must be taken into

account for stability.

• The working lift should be tied and butted to the main structure at approximately every

8m.

29.15.7 working platform

• The platform at the top of the scaffold, which only carries 0.75kN/m2, should be closely

boarded and should cover the whole plan area.

• Other platforms may be erected at any lift in the side bays and all requirements are

similar to any normal working platform.

29.15.8.1 toeboards and guardrails

• Guardrails and toeboards are required at every side of all working platforms from which

men and materials can fall more than 2m.

• Toeboards and guardrails should be fitted on the inside of standards to prevent outward

movement.

• Toeboards must rise at least 150mm and the main guardrail must be at least 910mm

above the working platform.

• There must not be an unprotected gap of more than 470mm in height in the means of

protection against a person's fall. An intermediate guardrail or other form of effective

barrier (eg brickguard frames) must therefore also be fitted. Where materials need to be



PART TWO



stored above toeboard height, additional boards, brickguards or similar mesh must be

fitted to prevent the fall of such material.

29.15.9 means of access

• Ladders provided for access purposes must be supported only by the stiles resting on a

firm, even base.

• The stiles should be lashed or clamped to a ledger or transom near the top to prevent

slipping both sideways and outwards.

• Ladders should be set at a working angle of 75° to the horizontal, i.e. one metre out for

every four metres of height and extend sufficiently above platform level to provide

adequate handhold at the stepping-off point. A distance of 1.05m (5 rungs) is

recommended.

• Rungs at stepping-off points should be on a level with the working platform.

• Ladders required to rise more than 9m of vertical height should have an intermediate

landing place provided -properly protected with guardrails, etc. as described above.

Toeboards are not required unless the landing place is used for the storage of

materials.

29.15.10 essential details

• Standards are to be not more than 2.50m centres in each direction.

• Ledgers for the first lift may be fixed at a maximum height of 2.50m and thereafter at 2m

vertical intervals.

• Bracing Single lift - diagonal bracing to every sixth bay in each direction.

• multi-lift- either diagonal bracing from top to bottom or zig-zag bracing in every sixth bay

in each direction.

• tying by transoms or ledgers abutting surrounding structure; the use of push/pull fixings,

or with box ties around columns.

• centres to be at a maximum of 8m. There should be at least one tie for each 40m2 of

vertical surface area.

29.16 SUSPENDED SCAFFOLD (NOT POWER OPERATED)

The following applies to all hand operated suspended scaffolds, together with associated

equipment, whether temporary or permanent :

• all ropes, winches, blocks and tackle must be strong enough and correctly rigged.

• safe anchorage for the suspension must be provided.



PART TWO



• have brakes which apply when the operating lever is released.

• be protected from the weather, falling dirt etc.

• maintained in good condition and platforms prevented from swaying whilst in use.

• steel wire rope must be used for the suspension of all platforms other than lightweight

cradles.

• lightweight cradles may be suspended by fibre ropes and pulley blocks which should not

be more than 3.20m apart. (only ropes recommended by manufacturers should be used).

29.16.1 outriggers

• be long enough and strong enough.

• be horizontal (light cradles are excepted).

• have stops at their outer ends (light cradles excepted).

• be tied down or properly counterweighted at the tail.

• be close enough together to support the rails and scaffolds properly.

29.16.2 counterweights

• be bolted or securely attached to the outriggers.

• be at least three times the overturning movement of load.

29.16.3 platforms

• hung clear of the building or face of the structure.

• be close boarded.

• be at least 430mm wide on lightweight cradles.

• be at least 600mm wide on all other types if used only for workmen, or be at least 800mm

wide if used for workmen and materials.

• never be used to carry another higher platform.

29.16.4 runways

• strong enough and in good condition

• have stops at each end

• be bolted or tied securely to their supports

29.16.5 suspension ropes or chains

must be properly secured, both overhead and to the frame of the platform



PART TWO



29.16.6 winches

• must have at least two full turns of rope on the drum when platform is in its lowest

position

• be marked with the length of rope on the drum

29.17 SLUNG SCAFFOLDS

The following standards apply to all slung scaffold which are suspended at a fixed height,

either below load-bearing projecting brackets or beams, or from the structural members of a

roof or other overhead structure. (see Fig.16)

29.17.1 suspension

• only tested wire ropes, chains or scaffold tubes may be used

• tested wire ropes should be secured to the overhead supports and to the ledgers of the

working platform as close as possible to junctions with transoms by two full round turns,

and the end held with three bulldog grips or woven or tested eye and shackle.

29.17.2 working platform

• ledgers should span suspension points and be set at about 2m centres. (2.5m maximum)

• transoms at 1.50m centres, should rest on the ledgers

• platform should be close boarded and evenly set with each board adequately secured

29.17.3 toe boards and guard rails

• toe boards (150mm above platform level) and guard rails (9110mm to 1.15m above

platform level and 765mm above top of toe boards) will normally be necessary on all

sides of the platform.

• angle couplers and a check coupler used at each end of the hanger.



PART TWO



29.18SUSPENDED ACCESS EQUIPMENT

29.18.1 general

Suspended access equipment is most

frequently used for painting, glazing,

scaling, cleaning and light repair

work on tall buildings or structures

above busy streets. (see Fig.17)

Guard rail to perimeter of deck, connected to wire by purpose made fitting complete with toe boards

38mm thick boards

Max grid of wires 2.5 x 2.5

2 round turns of wire and 3 bulldog grips

2 round turns of wire and 3 bulldog grips

Alternatives

Fig.16 - Showing all the safety features required when erecting a suspended scaffold.

Fig.17 - Showing a typical unhinged electrically powered

suspended cradle. Cradle is fitted with toe

boards and full guard rails.



PART TWO



All suspended access equipment incorporates the following elements:-

• a cradle or working platform

• suspension ropes and hoisting equipment

• a temporary or permanent roof rig to which the suspension ropes and cradle are

attached.

Suspended access equipment normally falls into two classes:

• those relying on counterweights for stability (usually temporary installed)

• those which are structurally attached to the roof or top part of the building (usually

permanently installed).

29.18.2 installation and rigging

Before installing or rigging suspended access equipment you should ensure that:

• installation is carried out by an experienced cradle erector.

• all equipment is thoroughly examined by a competent person after installation and /or

rigging and before being put into service.

• Particular attention is paid to the safety of those installing or rigging the equipment to

ensure that they are provided with appropriate means of fall prevention or fall arrest.

29.18.3 stability

All equipment relies on some form of roof rig to support the suspended platform. The

cantilevered portion of the roof rig consists of outriggers, which may be metal joists, timber

poles, scaffold tube framework, etc.

The following are the main points to consider when assessing the stability of any suspended

access equipment:

• roof rig should be designed by a competent engineer who should ensure that that the

supporting structure is able to withstand the imposed loading.

• when traversing tracks are used they should be set as nearly horizontal as possible.

• spacing of outriggers should be determined with reference to manufacturer’s

specification and the loads to be carried.

• where counterweights are used as the means of holding down the inboard end of an

outrigger they should be marked with their weight and firmly attached to the outrigger.

(Bags of sand, cement etc. are not appropriate counterweights).

• all outriggers must be strong enough to carry the weight of the suspended platform and

its load, with the appropriate safety factor.



PART TWO



29.18.4.1 working platforms

guard rails and toe boards

Whatever type of working platform is used, toe boards, at least 150mm high, and a main

guard rail at least 910mm above platform level must be fitted. A further guard rail, or other

suitable barrier must also be fitted so that the gap between any guard raill or barrier and toe

board does not exceed 470mm.

decking

Decking of the platform, which must be at least 600mm wide, should have a sound, slip

resistant surface and should be fixed so that it cannot be accidentally displaced. Except to

the extend necessary for drainage, the decking should be close – boarded, or plated.

29.18.5 prevention of falls

In order to prevent the access equipment from falling in the event of a rope failure, the

suspension system should include a secondary rope and fall arrest device.

Where it is not practical to fit a safety rope, each operative should be provided with a

suitable safety harness and lanyard of appropriate length which should be attached to an

independent safety line secured to a safe anchorage of the building.

29.18.6 electrically operated equipment

Equipment should be installed in accordance with the IEE Regulations for Electrical

installations and operated to ensure compliance with the Abu Dhabi Water and Electricity

Departments (ADWEA) Regulations.

The power point should be accessible at all times, and, when work is in progress, there

should be a notice clearly displayed to warn that power must not be switched off.

Power cables should be:

• looped and secured at roof level to prevent any risk of them being pulled out of their

sockets.

• cables and connections should not be allowed to lie in gutters where water can collect.

• pendant cables must be robust and of adequate length to allow for planned movement of

the platform.

Provisions must be made for winching operatives to safety in the event of a power failure.

All control units should be so marked that there is no confusion as to the purpose of various

controls.



PART TWO



29.18.7 operation

Suspended access equipment must be operated strictly in accordance with manufacturers

recommendations. It is recommended that the equipment is checked daily.

Main requirements:

• only trained people should be allowed to work on suspended access equipment.

• supervisors should be experienced and competent in the whole operation.

• working platforms should be raised and lowered with care so thaat they remain as near

horizontal as possible.

• mobile roof rigs should not be moved whilst operatives are on the platform.

• when work is being carried out from the platform , or it is left in place between periods of

work, it should be tied to each end of the building to prevent undue movement.

• a suitable emergeny procedure should be established and understood by all those

involved in the work.

• when left in position unattended, care should be taken to ensure that unauthorised

persons cannot easily reach trailing ends of suspension or safety ropes. Similarly, all

electrical gear should be out of reach and effectively isolated

• suspended access equipment should only be used for the purpose for which it was

intended. It should never be used for transferring persons from place to place.

• platform and equipment should be regularly washed down (taking care to prevent

wetting any electrical equipment).

• Precautions for the protection of the public, such as the provision of ground level bariers,

must always be considered in the use of suspended access equipment



PART TWO



29.19 SUSPENDED SAFETY CHAIR (BOSUN’S CHAIR)

Standard requirements (see Fig.18 & 19)

• must only be used by one operative at a time.

• all operatives using this equipment must be thoroughly trained.

• may be used only where the work is such short duration as to make all other forms of

suspended platforms not reasonably practicable.

• may be suspended on one or more blocks using fibre or wire rope.

• may be manually or mechanically operated.

• swivel connection must be fitted at the suspension point to prevent spinning.

• all ropes should be thoroughly examined before use for sign of wear.

• chair should not contain any loose material.

• in use, fall rope should always be maintained under, or around the cleat to act as a break.

• loading calculations should be based on a SWL of 115kg.

T O

C

Fig.18 - Showing Safety Factor using counterweight: The counterweight ( w ) x tail length ( T ) Should be at least four times the projection length

(O) x weight of fully loaded chair ( C ).

Securely fixed to support of adequate strength.

Single sheave pulley blocks.

Hook either moused or fitted with safety catch

Tying off point for handline.

Chair to B.S. 2830

Fig.19 - Showing Bosuns Chair and fittings meets all the requirements of B.S. 2830.

Chair size should be:-

• between 450mm and 610mm wide

• not less than 225mm deep

• have a back not less than 250mm high above seat.



PART TWO



29.20 SAFETY NETS

Safety nets should be erected as close as possible to the working level, and if on the outside

of the structure, should be higher at the outer edge than at the inner.

Two main types of safety nets are available

personnel nets

100mm mesh. Intended to catch a man

falling from above. (see Fig.20)

material or debris protection nets

Smaller mesh 12mm-19mm, intended to protect those below from falling objects. (see

Fig.20)

29.20.1 general requirements

• size and siting of the net are of

critical importance, the

recommended distance a person

should fall before encountering a net

is 6meters.

• for a fall of 1meter, the net must have

a horizontal projection beyond the

outermost working point of 2.2meters,

while for a fall of 6meters a projection

of 3.2meters is necessary.

• erection of safety nets should be

carried out by qualified persons in

compliance with standards and should

ensure that any supporting framework

can withstand impact or shock

loadings, and the framework itself

does not present a hazard to

personnel who may fall into the net.

(see Fig.21).

Sterling personnel safety net. 17,500 ft. pound test.

100 mm mesh.

Material/debris net 3/18” sq 12mm x 19mm Double Layer Throughout.

Fig. 21 - Showing Typical type of combined debris and personnel net used during steel erection.

Fig.20 - Showing both Man Safety and Debris nets.



PART TWO



• When erecting nets in the vicinity of electricity lines or overhead power cables, the

appropriate authority should be consulted before work is commenced.

• nets should be securely attached to support

framework with tie cords, hooks rings or

thimbles spaced at a maximum of 750mm. The

actual tie should be at least double the strength

of the net, and if hooks are used, they must

have positive locking of some description. (see

Fig.22)

• nets can be outrigged on scaffolding provided that the scaffold structure is securely tied

into a building or similar.

• a safe exit from the net must be provided for anyone who falls into it.

29.20.2 markings on safety nets

The safety net should bear a label marked with:-

• name/trade mark to identify the manufacturer.

• normal size of the safety net.

• british /european standard.

• date of manufacture.

• deflection at centre of net during prescribed test.

• maximum distance below the working height at which the net is designed for use.

29.20.3 test certificate

Supplied by the manufacturer, stating:

• type of net

• breaking strength of:

∗ mesh

∗ border cord

∗ under test

• height of drop withstood and deflection at centre when proof net tested.

Fig.22 - Showing Hook with safety catch used to attach safety net to a suitable support framework.



PART TWO



29.20.4 periodic testing

Safety nets are provided with short lengths of test cord attached, normally eight.

At intervals not exceeding three months one cord should be tested and a record kept. For

net use after two years (ie eight times three months) or if there is any deterioration, advice

should be sought from the manufacturers.

Nets should be inspected weekly for damage, loose ties etc together with the framework and

anchorage points. All such inspections should be recorded.

Test cords must never be used as tie cords.

29.20.5 care and maintenance of nets

care

Care should be taken to reduce to a minimum unnecessary wear and mechanical damage

likely to weaken the net. Materials must not be stacked on it and deliberate jumping onto, or

dropping of objects into nets must be prohibited. The following sources of damage or wear

should be avoided as far as possible.

• dragging over rough surfaces

• contact with sharp edges

• accumulation of debris in the net

• sparks etc from welding and burning operations, hot gases from blow lamps, hot ash from

chimneys or furnaces

• chemical attack

maintenance

Regular inspection is necessary to ensure the nets remain serviceable. The net

manufacturer should be consulted when there is any doubt about the suitability of nets for

use in hazardous conditions, or after any known contamination.

It is necessary to wash nets occasionally and always before storing in order to remove grit

and soot and prevent abrasion. If contaminated by acids or alkalis, nets should be well

washed, preferably by hosing and allowed to dry naturally away from heat. Man-made fibre

nets may be stored wet without loss of strength, but natural fibre nets should always be dried

first.

29.20.6 storage

• wet nets should be dried naturally.

• nets should not be stored in a wet state (risk of rot with natural fibre nets)

• storage cupboards to be well ventilated (nets hung if possible)

• nets should be turned periodically to allow air circulation.

Note: Safety nets are intended to save lives and prevent injury; they are not

receptacles to catch unwanted items.



PART TWO



29.21 MOBILE ELEVATING WORK PLATFORMS (MEWP'S)

Mobile elevating work platforms (MEWP’s) are classified as lifting equipment for lifting

persons. They are designed to provide a temporary working platform which can be easily

moved from one location to another. They are particularly suitable for short duration tasks,

where the use of a ladder would be unsafe or the erection of a scaffolding platform, time

consuming or impracticable in relation to the job to be done. Some units have specialised

applications eg under-bridge work.

There is a number of differing types of MEWP. They can be classified according to:

• the type of carrier or chassis and

• the type of elevating structure

29.21.1 principal types of carrier

road vehicles

Most have hydraulic stabilisers and are stationary when in use. Some small platforms can

operate off locked-out suspension systems allowing low speed travel with the work platform

elevated.

trailers

Designed to be towed on the highway. Usually come with low capacity range. Most have

manually deployed stabilisers of the screw jack type and are stationary when in use.

self propelled

The superstructure is mounted on a purpose-built chassis designed to allow the machine to

be driven at slow speed with the boom and chassis in access use. The machines are

controlled from the working platform (with secondary controls at ground level).

29.21.2 principal machine types

scissor lifts (see Fig.23)

Generally vertical lift only. May be fitted with outriggers, depending on size and height to

which lift extends.

telescopic boom or jib (see Fig.24)

Gives direct straight line approach to the point of work but has a limited ability to clear

obstructions between the vehicle and the point of work.



PART TWO



articulating boom (see Fig.25)

Gives a wide range of reach and height, with platform mobility.

combined telescopic and articulating boom (see Fig.26)

Gives maximum flexibility.

29.21.3 precautions (all types)

It is essential that the correct type of plant is specified for the intended work and the work

location is inspected for hazards. In particular, overhead electric cables or other obstructions

should be identified. If the working area is traversed by other vehicles or pedestrians,

temporary barriers, cones, etc should be used.

Fig.23 - scissor lifts

Fig.24 - telescopic boom

Fig.25 - articulating boom

Fig.26 - combined

telescopic &

articulating boom



PART TWO



1. If outriggers are fitted, check they can be fully extended in the working area.

2. Check machine is level or can be levelled.

3. Check the ground is firm and will support loadings. Use adequate packing if necessary

under outriggers. Avoid basements, cellars, sewers, drains, manholes, old trenches,

joints in concrete, and cracks.

4. Only trained persons should be allowed to operate a MEWP. Operators should have

received training for the relevant class of machine and, in addition, should receive

familiarisation training for the particular make and model to be operated. Such

familiarisation training is typically provided by plant hire companies when a MEWP is

delivered to site. It does not constitute adequate training in itself.

5. Safety harnesses should be worn at all times by personnel working from the platform.

Harnesses must be attached to purpose-designed anchorage points (if provided) or

other suitable anchorage points as indicated in the manufacturers' instructions. Note that

the top guard-rail of the working platform may not be suitable as an anchorage point.

6. The safe working load must be clearly marked at the base of the machine and on the

working platform. The load specified must not be exceeded. Care needs to be taken to

reduce the build up of debris and material on the platform. Telescopic and articulating

machines are normally designed to carry operators and tools only. Scissor lifts may have

the capability to carry some materials. Manufacturers' instructions must be followed.

7. Persons should not leave the working platform whilst in an elevated position, nor

should materials be transferred.

8. Step ladders or hop-ups must never be used on the working platform to gain extra reach

or height.

9. MEWPs must only be used within the manufacturers recommended wind speeds. This

may necessitate a wind speed indicator being available.

10. If MEWPs are self-propelled, the operator must walk the intended route to identify any

hazards before commencing the operation. Travelling on inclines must only be carried out

within the limits specified by the manufacturer. Most MEWPs have very low gradient

tolerance and are fitted with tilt alarms to warn when the limits are exceeded.

11. MEWPs are fitted with emergency (auxiliary) lowering controls and an emergency stop

switch. Before using a MEWP the operator(s) and another responsible person on site

(who is not working on the platform) must know how to use the emergency controls.

12. On completion of the work, the MEWP should be parked in a designated area. It should

never be left in a raised position. The MEWP should have the engine/ motor switched off

and the key removed.



PART TWO



29.21.4 MEWP operator's daily safety checklist

from ground level

1. Check that manufacturer's handbook is with the machine.

2. Check fuel, water and oil levels and that batteries are fully charged. Ensure batteries are

secure, clean, free from corrosion and electrolyte level is adequate

3. Check the machine starts and that the emergency stop button (engine cut-out) works.

4. Check that tyres are free from significant damage and are inflated to the correct pressure.

Check that wheel nuts are in place and properly tightened.

5. Check structural parts for visible cracks or damage.

6. Check that the hydraulic system is free from leaks and that cables are in good condition.

7. Check that pins and retainers are in position and in good condition.

8. Check that signs identifying the controls, SWL, crush points, etc are in place and

readable.

9. Check that all powered movements for telescoping, raising, lowering and slewing are in

good working order.

10. Check that emergency lowering controls are fully functional. Always refer to

manufacturer's handbook.

from the working platform

1. Check that the platform structure is in good condition, clean and free from grease and

dirt, and that cage door locks are fully functional.

2. Check that decals identifying the controls, SWL, harness anchor points, maximum wind

speeds, etc are in place and readable.

3. Check that all powered movements for telescoping, raising, lowering and slewing are in

good working order.

4. Check that emergency lowering controls are fully functional.

5. Test lights and horn, when fitted.

6. Check that the steering controls function correctly in forward and reverse.

7. Test brakes to ensure that they are working efficiently in forward and reverse.

8. For machines designed to travel while the platform is raised, check that the "drive speed

is restricted when the platform is in the raised position.

NB When carrying out these checks operators must not work under a raised boom or

platform unless movement has been prevented by means of suitable locking devices.

SECTION 30

SECTION 30

ERECTION OF STRUCTURES

INTRODUCTION 1


30.1 DESIGN AND PLANNING 2

30.2 SITE CONDITIONS 3

30.3 SPECIFIC SITE ACTIVITIES 4

30.4 STABILITY OF STRUCTURES 8

30.5 ACCESS AND WORKING PLACES 9

30.6 PERMANENT ACCESS 13

30.7 TRAINING AND SUPERVISION 14

ERECTION OF STRUCTURES SAFETY CHECKLIST

(ADM/H&S/CL/2.30/1)



PART TWO


ADM/H&S/Pt 2 01 March 2005 ERECTION OF STRUCTURES 1 of 14

SECTION 30

ERECTION OF STRUCTURES

INTRODUCTION

The erection of structures can be both difficult and dangerous. Many fatal or serious accidents occur

during the erection process, the principal cause being falls from heights, either from working positions

or whilst gaining access to them. Other accidents occur because of structural instability during

erection and whilst handling, lifting and transporting materials.

This section of the manual, therefore, is designed to give guidance on the correct method of erecting

structures by establishing safe erection procedures and implementing them through effective

management control.


Ministerial Order No. (32) Year 1982 Article (19) B

Ministerial Order No. (32) Year 1982 Article (20)



PART TWO



30.1 DESIGN AND PLANNING

The designer should consider the risks to health and safety during construction,

maintenance and subsequent demolition.

For example, instead of assuming that construction work will be carried out insitu at height, it

would be better if the work was designed to be prefabricated in a factory, cast or assembled

with much greater safety on the ground at the site, and subsequently hoisted into position.

If the work can incorporate safety provisions such as edge protection or access provision, so

much the better. In this way the designer can eliminate some of the risks to health and safety

through the design and perhaps, also contribute positively to the quality of the completed

structure.

It is important to realise that the general term “design” can refer to all stages, from concept

through to main structural design and detailing. This is relevant to design for both permanent

and temporary works.

Planning for safe erection should commence at the initial design stage with designers taking

into account the need for, and the practicality of, safe methods of working during erection.

essential considerations to be assessed at each design stage include:

• stability at all stages of erection of the assembled structure, individually assembled

portions and single components.

• effect of the erection sequence on stability; where this is critical, the sequence should be

stipulated.

• realistic assessment of loadings at all stages of construction.

• provision of safe access and working places.

• ease of connecting components, e.g. by the provision of landing cleats, which allows a

beam to be safely located whilst suspended from a crane, and cut out the need to align

manually by podger.

• safe handling, lifting, storing, stacking and transportation of components, depending on

their size, shape and/or weight.

• for sub-assemblies, it is critical that overall weight and lifting points are identified on

drawings.

Design specifications should incorporate particular requirements and essential information

for the scheme to be planned and erected safely.

30.1.1 method statements

Preparation of a written method statement setting out the proposed erection scheme is an

important part of planning for a safe system of work.

The extent of detail in a method statement will depend upon the size and/or complexity of

the work. Before work commences on site, outline proposals produced at tender stage

should be developed into a method statement.



PART TWO



method statements should include but not be limited to the following:

• a detailed erection scheme.

• should be distributed to all those concerned with supervision of the erection.

• erection monitored to ensure that the planned sequence of operations is not deviated

from in any way.

• be reviewed and updated as necessary so that it remains current.

such information should include:-

• phasing of the work, particularly with that of other affected contractors.

• special requirements relating to the safe erection of the structure should be highlighted

at the pre-contract stage, (e.g. the need for temporary bracing/guying or the use of

mobile access platforms).

• site conditions

• ground conditions

Checklists for the production and checking of method statements relating to steel

erection, pre-cast concrete and timber frame erection are provided at the end of this

section.

30.2 SITE CONDITIONS

30.2.1 ground conditions

An important aid to safe erection is the provision of hard standing ground, suitable for mobile

access equipment and cranes prior to the commencement of erection.

This is particularly helpful for single storey work, when fixing sag bars. Good vehicular

access on to the hard standing ground should also be provided, and ground loadings and

vehicle turning circles must also be taken into account.

preparation and bases

A sound foundation is necessary for each column and should be capable of accepting both a

vertical load and also the additional horizontal thrust which is developed as soon as

temporary props have been removed.

Pre-cast frame columns are usually inserted into sockets cast into the foundation blocks and

consequently are required to be held temporarily in place after alignment. Wedges and

props are used for this purpose until the column has been made secure by grouting. Other

types of pre-cast columns incorporate a steel base plate, similar to the base of a

prefabricated steel column.



PART TWO



30.2.2 hazards and limitations

main points to consider:-

• access to erection areas, with regard to adverse ground conditions likely to contaminate

the erector’s footwear and increase the risk when aloft.

• site hazards and limitations.

• overhead electric power lines. (See Pt 2 section 6) – Overhead and Underground

Services.

• buried services, including underground electric cables, gas or other pipelines.

• restricted access to, and on, the site due to road alignment which may limit the size and

weight of structural members and plant, including cranes.

• restricted space for erection, maneuvering, storage and, if required, for on-site pre-

assembly manufacture of fabrication, low ground bearing capacity which may be due, for

instance, to made-up ground, or existing underground services or structures.

• proximity and condition of other buildings, roads, railways etc., which may affect the

planned method of erection and craneage.

• proximity of the general public to the site.

• activities of other contractors.

• area of the site affected by erection operations should be designed as a restricted area.

• barriers and notices should prohibit entry to non-erection personnel.

• toxic gases, chemicals, fluids or dust emitting from processes on or near the site.

30.3 SPECIFIC SITE ACTIVITIES

30.3.1 holding down bolts

• should be loosened off immediately after compaction of the concrete by rotating them in

their sleeves.

• are generally designed only for the loads experienced by the completed structure, and

are not always suitable far the more severe conditions encountered during early stages of

construction.

• will give rise to the danger of collapse, unless adequate temporary bracing is provided in

the form of props or guys.

• adequate supplies of steel plate packing pieces should be provided for use in levelling

prior to grouting operations once the frame is erected, lined, and levelled.

• essential that they are maintained tight.



PART TWO



30.3.2 cranes/material handling and slinging

Safety during lifting and handling requires careful consideration of all aspects of the methods

and systems to be used.

Factors specifically relating to the use of cranes, which should be co-ordinated, include:

• organising the appropriate number and

type of cranes, bearing in mind that

the choice could be limited if cranes are

to be hired locally.

• confirming that the designated siting

positions for cranes can be achieved,

with suitable hard standings provided.

• checking for the presence of hazards or

development which may have altered the

site since the original plans were made

• appointing a competent person to

supervise the complete lifting operation,

particularly when tandem lifts are used.

• suitable facilities, ladders, etc., must be

available to ensure a safe place for

persons unloading vehicles.

• when loads are of a consistent size, the

provision of a gantry, or a safety

harness fixing point should be

considered.

• all fabricated units should have a distinctive mark identical to the erection drawings, in

order to ensure that structures are correctly assembled.

cranes

Detailed guidance on types of cranes most commonly used in construction processes and

on the safety requirements applicable are given in (see Pt 2 section 19). – Cranes & Hoists

manual handling

Care should be taken when manually handling components. Erectors should be trained in

the principles of manual handling, (see Pt 2 section 8) – Manual Handling.

lifting steel members:

• will normally be slung by the use of chain or flat slings in a conventional manner.

• in the case of concrete units, it is not safe to attach slings to projecting reinforcing steel.

One of a number of types of proprietary lifting devices cast into the concrete, should be

used.

• it is essential that the manufacturer’s instructions regarding installation and loading are

followed

• pre-cast units may have to remain attached to the crane until they are secured by

temporary props. In such cases, proprietary remote control devices, which can be

operated by the crane driver or the fixing contractor’s supervisor when the unit is safely

secured, may be valuable.



PART TWO



slinging

General principles of slinging are covered in Pt 2 section

20 - Lifting Gear.

sling release

Of prime consideration in slinging

structural steel members is the way in

which the slings may be released without

placing the erectors at risk.

This may be achieved in a wide variety of

ways, including the use of remote

release shackles. (see Fig.1)

slinging materials

Materials may be slung in cradles, e.g. purlins in

purlin cages, which avoid the necessity of the

erectors manhandling purlins whilst moving along

the truss, portal, etc. (see Fig.2)

Consideration must also be given to the stability

and security of materials being lifted in case of

accidental impact of a suspended load with part of

the works, for example, when threading a load into

a partially completed steel frame.

Fig.1 - Showing a remote release shackle device used during column erection.

Rubber belt.

Pin

..

Operating

ropes.

Fig.2 - Type of Purlin Cage commonly used to transport steel trusses safely,



PART TWO



30.3.3 material storage

Areas should be allocated for stacking and storing components and should be clearly

marked on site plans.

these areas should be:

• clear of obstructions, reasonably level, and of adequate size,

• on ground which is capable of withstanding loads imposed by the stored materials and

plant used in the area (investigation should include a check for the presence of

underground services in order to prevent damage from imposed loads),

• sited away from hazards such as overhead power lines,

• arranged so that clear access and lines of sight are provided and maintained between

stacks of components.

• provided with artificial lighting and weather protection, where appropriate, to aid handling.

• if on site manufacture fabrication modification or repair work is to be undertaken,

additional areas may be needed with facilities similar to those of storage areas.

stacking

Matters which should be taken into account when stacking or de stacking components

include:

• methods of stacking which ensure that no risk of collapse or sliding is induced.

• adequate supply of timbers, battens and wedges, which should be of suitable size and

strength.

• safe access for slinging purposes.

• components used to aid erection should be stacked on suitable timber battens and

packing pieces.

• not brought into contact with the ground, thereby preventing mud deposits which could

present a slipping hazard,

• prevent damage to projections, such as nibs and brackets.

• slings can be positioned easily around components.

• remote release shackle used during column erection.



PART TWO



Advantages can be gained in using

specialised devices such as mobile or

transportable storage racks or platforms,

particularly for small or common

components Such racks or platforms

should be designed to be stable when

some, or all of the components are

removed. They should be clearly marked

with a safe working load and self weight.

(see Fig.3)

30.4 STABILITY OF STRUCTURES

The requirement for stability at all stages of erection should be clearly understood by all

persons dealing with the erection work.

Particular care should be taken to verify stability in the following circumstances:

• temporary cessation of work.

• when fastenings may be incomplete, for example, in course of lining up and adjustment

of level,

• high wind or when high winds are expected.

• when the stage of completion of permanent work (for example brickwork, concrete, etc)

on which the stability depends is inadequate, or when the permanent work has not

developed adequate strength.

• when the structure or parts of it may be subject to construction loads for example - due

to impact, stacking of parts, and lifting or freeing of components which may have

become inadvertently wedged in position.

temporary supports (when specified) should be:

• of adequate design and construction as identified on drawings or on the method

statement,

• used in the way intended. Improvised supports should not be employed.

anchor points:

• should be such that they are able to resist any force likely to be imposed upon them.

• any movement of an anchor should be reported immediately and prompt remedial action

taken.

Fig.3 - Example of a transportable storage rack.



PART TWO



• steel cables for anchorage purposes should not enter the ground unless suitably

protected.

• fastening of guy lines to anchorages in the ground should be carried out using chains or

steel bars or sections.

• screw type anchors should be used in accordance with the manufacturer’s instructions.

30.5 ACCESS AND WORKING PLACES

The necessity to work at height can be reduced by the assembly of all possible items at

ground level and the erection of units into position in a semi-complete state. Items which

lend themselves to this application include vertical glazing or cladding rails, together with ties

and struts.

Various means of temporary access may be used in the erection of structures, and type of

equipment to be used must be carefully considered in the preparation of the method

statement.

platforms

they may be used in an inclined position for general access to heights, but they require a

firm base and must always be securely fixed; means of fixing, e.g. lanyards, should be

permanently attached to ladders.

ladders

in concrete structures, ladder fixings may be incorporated into the columns. Ladders may

also be used vertically for access up columns; they should be fixed to columns prior to

erection and must be capable of safe removal after erection. All ladders must be provided

with safe landing places no more than 9m apart

General guidance on the safe use of ladders is given in (see Pt 2 section 19). – Scaffolding

and Working Platforms.

holes in floors

where any hole is left in a floor through which a person may fall, it must be provided with

guardrails and toe boards or; alternatively, it must be covered over. Such covers must be

strong enough for the purpose and either be secured in position or marked to indicate its

purpose.



PART TWO



30.5.1 mobile elevating work platforms (MEWP’s)

The above are now the preferred type of access

and working place provided for the majority of

work at height, especially in steel erection.

A firm hard standing from which to work is

required, and erection must be carefully planned

so that previously erected parts of the structure do

not hinder the operation of the work platform. (see

Fig.4 and in Pt 2 section 29) - Scaffolding

30.5.2 man-riding skips and suspended cradles

Where it is not possible to use MEWPs, or

other equipment specifically designed for

lifting persons, then man-riding skips or

cradles suspended from cranes may be

used, as shown in Fig.5.

30.5.3 scaffolds

tower

used for making low level connection where the cost of powered plant would be prohibitive.

Further details on tower scaffolds can be found in (see Pt 2 Section 29).- Scaffolding

independent scaffolds

may be used in timber frame or panel construction, or for the construction of ladder access

towers.

Further details on independent scaffolds and safety requirements can be found in (see Pt 2

Section 29). - Scaffolding.

Fig.4 - Showing Type of Mobile elevating working platform (Commonly known as Cherry Picker)

Fig.5 - Type of 2 men Power operated Suspended Cradle complete with guard rails and dead mans operating handles.



PART TWO



purpose-built platforms

these are properly designed and fabricated

platforms which are used where a large number

of connections require fixing. They can be fixed

to components, e.g. the top of a column prior to

erection to avoid construction at height, and

can be removed for re-use at a new location.

Example of a close-boarded working platform,

fitted to the column at ground level before

erection is shown in Fig. 6.

30.5.4 access along beams

If it is necessary for persons to gain regular access along beams from which they can fall,

e.g. the top of a concrete beam, or the top or lower flange of a steel beam, the walkway must

be at least 430mm wide, or 600mm wide, if used for the passage of materials. Guardrail, at

least 910mm above the walkway, and toe boards, together with an intermediate guardrail or

other effective barrier must also be provided so that there is not an unprotected gap of more

than 470mm in height. This form of protection should, where possible, be fitted before

erection.

Where the above requirements are not met, access of short duration only may be

permitted by the following means:-

beam straddling

Beam “straddling” is acceptable provided the size

of the beam is suitable and supervisors are

satisfied that the method is safe. In such cases,

the following conditions must be met:-

• person must be able to place each foot firmly

on the bottom flange and have both hands

gripping each side of the top flange as they

move along.

• upper and lower beam surfaces must be free of

obstruction so as to allow the above movement.

• person must be wearing a safety harness

attached to a secure anchorage. (see Fig. 7)

walking the bottom flange

where straddling is not possible, the practice of side walking the beam, with both hands on

the top flange and both feet on the same side of the bottom flange, is permitted provided

that:-

Fig.6 - Example of a close-boarded working platform, fitted to column at ground level before erection process.

Fig.7 - Showing Steel Erector straddling beam wearing a full safety harness attached to an overhead running line.



PART TWO



• flanges provide secure handhold and foothold, and

• the top flange is no higher than the person’s waist.

• the person must be wearing a safety harness attached to a secure anchorage.

30.5.5 safety nets and harnesses

Occasions will arise where recourse must be made to the use of safety nets and safety

harnesses.

Due to the lack of fixing points and the very short duration of work, such as bolting up, the

use of safety nets is often impracticable. However, where possible, brackets for the fixing of

such nets should be fixed to the beam prior to lifting, and provision mode for persons to gain

access to the fixing points and to handle the net.

Further details the use and safe installation of safety nets can be found in (see Pt 2 Section

29) –Scaffolding (Safety Nets).

safety harnesses

Where the use of safety nets is impracticable, safety

harnesses must be used, but it must be stressed

that the use of personal protection in the form of

harnesses must be considered a last resort.

The provision of a fixing to which the safety harness is

attached is of prime importance.

Where the fixing is to provide for movement along a

beam, it should be such that the harness does not

have to be released to allow such movement.

This can be achieved, for example, by the use of a taut steel wire rope set to run along the

beam. It should be stressed that any anchorage must be capable of withstanding the

likely impact loads. Where movement along a beam is necessary, then a fixing for a safety

harness may be achieved by the provision of additional holes at specific points on the steel

and the use of a proprietary device such as a girder grip. (see Fig.8)

Fig.8 - Example of a “Manuclave” type Girder Grip anchorage device.



PART TWO



Alternatively, the lanyard of the safety harness may be

wrapped around a structural member and clipped on to

itself, care being taken that it would not be damaged by

any sharp edge in the event of a fall. Such damage may be

prevented by providing a sheath around the lanyard. If

structural members are too large for the lanyard to be

wrapped around, steel wire rape of at least 8mm diameter

may be wrapped around a member to provide a fixing for

the harness. (see Fig.9)

self retractable fall arrestors

Consideration should be given to the use of a self

retractable fall arrester attached to a safety harness.

(see Fig.10)

This is particularly useful where a considerable

vertical movement is necessary.

Harnesses should be to BS EN 361 and the

incorporation of tool frogs and pouches will enhance

their use. If safety nets are used, they should be to

BS EN 263-1.

Further guidance on safety harnesses is given in (see

Pt 2 section 12)-PPE.

30.6 PERMANENT ACCESS

All permanent walkways, ladders and steps should be erected as early as possible to enable

the structure itself to be used for access. Edge protection must be adequate and temporary

guardrails should be fitted if the permanent rails are not available. Once an access route has

been established, gratings and boards should be removed only under a permit-to-work

system.

Fig.9 - Lanyard wrapped around a steel column and attached with a “Caribenna” type hook.

Fig.10 - Showing Type of fall arrestor fitted with a 40m. cable.



PART TWO





PART TWO



30.7 TRAINING AND SUPERVISION

An overall training programme should be planned for both riggers and supervisors, and

should include, but not limited to the following:-

• all aspects of rigging and erection methods, lifting equipment, use of tools and plant,

erection of scaffolds and stagings, together with safe working practices fall prevention

and statutory obligations.

• induction training for supervisory staff prior to, and to rigger/ erectors at, the

commencement of the project.

• project planning for structures

• establishment and running of the site organisation.

• procedures for dealing with emergencies and accidents.

• issue and explanation of the company safety policy, procedures and site rules, the

location of emergency telephones, first aid and medical services, and the use of

protective clothing and equipment.

SAFETY CHECKLIST - ERECTION OF STRUCTURES


ADM/H&S/CL/2.30/1 01 March 2005 SAFETY CHECKLIST - ERECTION OF STRUCTURES 1 of 1

CHECKLIST TO PRODUCE METHOD STATEMENTS

General

�� name(s) and address(es) of the contractors involved.

�� name and address of the site to which the method statement relates.

�� names of the supervisor / foreman and appointed safely adviser and arrangements for


�� description of the type of structure to be erected.

�� details of the personnel to be used and their training / experience.

�� details of PPE to be provided to personnel.

�� sequence of operations including starting points where this is critical to stability

Placing/erection of precast concrete

�� pitching/ Basing.

�� method of ensuring temporary stability of the assembled structure and components.

�� provision and maintenance of a safe place of work and means of acces/egress including:

�� vertical access including mobile elevating work platforms, ladders etc.

�� description of the work.

�� details of the personnel to be used and their training! experience.

�� details of PPE to be provided to personnel.

�� provision and maintenance of a safe place of work and means of access/egress including:

�� method statements for placing/erection of precast concrete.

�� name and address of the contractor involved.

�� name and address of the site to which the method statement relates.

�� names of the supervisor/foreman and appointed safety adviser and arrangements for


�� erection sequence and starting points(s).

�� method of ensuring temporary stability at all times.

SECTION 31

SECTION 31

DEMOLITION

INTRODUCTION 1


31.1 TENDERING 2

31.2 DEMOLITION SURVEY 2

31.3 PREFERRED WORK METHOD 3

31.4 PRE-CONTRACT ACTIVITY AND PRECAUTIONS 3

31.5 SEQUENCE OF DEMOLITION 5

31.6 DEMOLITION HAZARDS 6

31.7 DEMOLITION TECHNIQUES 8

31.8 SAFETY PRECAUTIONS FOR SPECIAL STRUCTURES 13

31.9 TRAINING AND COMPETENCE 14

CHECKLIST FOR DEMOLITION METHOD STATEMENTS

(ADM/H&S/CL/2.31/1)



PART TWO


ADM/H&S/Pt 2 01 March 2005 DEMOLITION 1 of 14

SECTION 31

DEMOLITION INTRODUCTION

Demolition can not only be one of the most dramatic operations in the building/construction industry, it

can also, by its very nature, be one of the most dangerous.

Demolition work varies very widely from the controlled collapse of large structures from using

explosives, mechanical plant and even down to hand demolition of walls.

Demolition operations must only be carried out under the immediate supervision of a foreman with

personal experience of the work, or, by men who have the necessary experience and training on what

safe methods to adopt.

MAIN APPLICABLE UAE LEGISLATION Ministerial Order No. (32) Year 1982 Article (19)



PART TWO



31.1 TENDERING

31.1.1 provision of information

The client has duties to provide information, where necessary, after making reasonable

enquiries, which will enable them to ensure the preparation of the initial health and safety

plan. This information could include details of the construction of buildings, plant in the

structure and known hazards such as any contamination of the structure, plant, or land by

current or previous use.

The health and safety plan should include sufficient information on which demolition

contractors may base their tenders.

31.2 DEMOLITION SURVEY

Prospective contractors must ensure that the information with which they are provided with is

sufficiently detailed to allow identification of any structural problems, and the risks associated

with any flammable or hazardous substance.

the survey should take into account:

• presence of adjoining or adjacent

properties, e.g. hospitals, where noise, dust

or vibration might restrict the method of

demolition,

• type of structure and its key elements,

• condition of structural members and the

contribution of floors, roofs, walls, etc.

• suitable access for the proposed method of

demolition and vehicle access for the

removal of waste.

• need for temporary works or shoring,

• confined spaces, such as old tanks

or process vessels,

• overhead or underground services,

• health hazards, such as lead dust or

paint, residues from previous

processes, or contaminated land etc.



PART TWO



31.3 PREFERRED METHOD OF WORK

Demolition should, when possible, involve methods which make it unnecessary for persons

to work at heights. If this cannot be achieved the following methods should be considered:-

• deliberate controlled collapse, which minimises work at heights and limits exposure to

such danger.

• use of a balling machine, heavy duty grab, pusher arm or shears.

• when work cannot be safely carried out from part of the building or structure, working

platforms should be provided.

such platforms can be:-

∗ tube and fittings or proprietary systems.

∗ man-riding skips or mobile power-operated work platforms.

Where it is not practicable to provide such platforms, safety nets or safety harnesses should

be used. Guidance on the provision of working platforms and safety nets is given in Pt 2

Section 29, and safely harnesses in Pt 2 Section 12.

31.4 PRE-CONTRUCTION ACTIVITY AND PRECAUTIONS

Once a demolition contract has been awarded, the following steps and precautions should

be taken before work starts:

31.4.1 method statements

Demolition Contractor to prepare and submit a method statement outlining their proposals for

dealing with the health & safety aspects of the work, with special emphasis on safe working

at heights, and the sequence of demolition.

A general checklist for producing such a method statement is provided at the end of this

section.

31.4.2 notifications

Demolition Contractor may be required to notify utilities such as ADWEA, SPD, ADGAS. etc.

to request for the following information:

• drains and sewers to be sealed to prevent vermin gaining access to the site.(detailed

plans where possible).

• arrangements for the isolation or diversion of overhead or underground services,

• arrangements for temporary supplies for site operations

• location of underground services, (with detailed plans where possible)



PART TWO



31.4.3 construction health and safety plan

The contractor must develop the initial health and safety plan so that it incorporates the

approach to be adopted for managing health and safety during demolition.

31.4.4 protection of the public

Demolition is frequently carried

out in heavily populated areas

and particularly high standards

of site protection, safe systems

of work and effective

supervision are therefore

needed.

It is a requirement that a fence,

not less than 2 metres high be

erected to enclose all

demolition operations. Fence

should not be capable of being

easily climbed and access

gates should be secured

outside working hours. (see

Fig.1)

Outside working hours, debris at ground level should be cleared, excavations should be

fenced, vehicles and plant effectively immobilised and electricity and gas supplies isolated

or enclosed and locked.

31.4.5 overhead and underground services

The survey should have identified the possible presence of any services and enquiry’s to

obtain more detailed information and assistance will have been made.

Further guidance on location of services and relevant precautions is given in (see Pt 2

Section 6). – Overhead and Underground Services.

31.4.6 flammable materials and gases

Where existing plant has contained flammable materials, special precautions must be

observed in order to avoid fire or explosion.

The assistance of a competent analyst may be required to identify residues, carry out air

monitoring and assess whether pockets of contamination remain. Any residual flammable

material must be rendered safe by, for example, cleaning, purging or the application of an

inert gas.

Fig. 1 - Showing a typical of 2 mtr. high fence securely weighted with concrete blocks which would be the minimum required during demolition operations.



PART TWO



Where it is necessary to enter plant for cleaning or assessment purposes, the use of

breathing apparatus may be required, and a strict permit-to-work system should be

employed. (see Pt 2 section 11)

The fittings for any electric lighting used in such circumstances must be suitable for use in an

explosive atmosphere and conform to BS 5345: Electrical apparatus for use in potentially

explosive atmospheres.

31.5 SEQUENCE OF DEMOLITION

The design of a building will normally determine the sequence of demolition. In many cases,

this should be in the reverse order to the erection of the building and this will normally apply

to hand demolition where the required sequence will be established from the design of

individual columns, beams and floors.

In the case of mechanical demolition, the design of steel framed, reinforced concrete and, in

particular, pre-stressed concrete buildings or structures, may also determine the overall

sequence; the design will certainly determine the extent of any pre-weakening that can be

done prior to a deliberate collapse.

A sequence of operations must be established which allows debris to be cleared on a regular

basis, so that floors do not become overloaded and horizontal pressures on the walls is

avoided.

31.5.1 restricted areas and safe distances

Areas affected by each phase of the work, to which access will need to be restricted or made

safe, should be set out in the method statement.

Restrictions and control may be necessary during:-

• the dropping of debris.

• the operation of demolition plant.

• pre weakening activities.

• deliberate collapse or pulling over of buildings.

during debris dropping, the following main points should be observed:

• a radius of 6m, or half the drop height (whichever is the greater), should be used to

determine the restricted area to be kept clear

• a space of 6m minimum width from the face of the building to be demolished should be

allowed for the operation of cranes, grabs, balling machines, pusher arms and similar

equipment.



PART TWO



• If wire rope pulling is used, a distance of three quarters of the exposed length of pull rope

should be allowed an either side of the rope, and also behind the winch or pulling vehicle.

• when tall structures are being felled, a distance of not less than twice the total height

should be allowed along the proposed line of fall to cater for parts coming free in flight, or

bouncing and rolling on impact.

• structures should be felled into clear areas

• on slender structures, a 20 degree arc either side of the line of fall should be clear of

obstructions, and an area of radius not less than twice the total height should be cleared

of persons before the actual felling.

31.6 DEMOLITION HAZARDS

31.6.1 health hazards

Health hazards in demolition arise primarily from substances which are inhaled or ingested,

or which can react with or be absorbed through the skin. Noise and vibration are also

hazardous to health.

In demolition, it may not be practicable to control these hazards by means such as exhaust

ventilation and emphasis should therefore be placed on the following:-

• using processes which do not generate hazardous dust and fumes,

• segregation of workers,

• operating work permit systems to reduce the numbers exposed to risk,

• ensuring that suitable personal protective equipment is provided and used,

• ensuring that airborne hazards do not escape from the site to affect members of the

public.

lead

Lead as a toxic dust or fume arises from cutting and burning steelwork covered with lead

based paint and the handling of old petrol tanks from filling stations.

In demolition, it is essential to identify any lead paint or lead-containing material before

operations begin. If adequate information is not readily available, a sample of the paint or

material should be analysed to determine the lead content.

The cutting of steelwork often has to be carried out within the confines of a building, where

the dust and fume has little chance to disperse and there is risk of a very rapid absorption of

lead, Under these circumstances, exposure should be assessed.

Where information on lead-in-air concentrations from a particular type of work is lacking, air

monitoring should be carried out. Assessment should be made when exposure is likely to be



PART TWO



at a maximum level. Monitoring may not be necessary for work where there is a clear need

for the wearing of respiratory protective equipment but, if other persons are working, or likely

to be in the vicinity, air monitoring may still be needed to ensure that such persons are not

exposed to risk..

Where persons are likely to be exposed to concentrations above the lead-in-air standard,

suitable approved respiratory protective equipment must be provided and used.

Arrangements should be made for such equipment to be cleaned and stored at the end of

each shift, and to be regularly maintained.

asbestos

Asbestos dust will be generated whenever demolition involves work on asbestos in sprayed

coatings, thermal and acoustic insulation materials, fire resistant walls and partitions,

asbestos cement sheets, or flooring materials.

Asbestos insulation or coating should be removed by specialist contractors only, and,

where possible, before any other demolition work is started.

Clients should ensure that contractors have relevant experience and knowledge of the

necessary precautions when dealing with Asbestos.

PCB’s

PCBs (Polychlorinated Biphenyls) are toxic substances which were used as dielectric filler

fluids in electrical transformers and capacitors and are still used in some refrigeration and

heating equipment.

In demolition it is important to identify equipment containing PCBs, either from labels, or by

enquiry’s from manufacturers or former owners. Where equipment is to be removed or

transported, leakage of PCB fluid is always a danger and checks for leakage at welds or

flanges must be made. If equipment is to be dismantled or broken up, it is essential that the

fluid is removed first.

Drainage of PCB fluid must be carried out in an open or well ventilated area and full

protective clothing including respirator and chemical eye protection, must be worn.

Note: Waste PCB fluid must not be disposed of by pouring into drains, on to land, or by

burning other than in a licensed incinerator.



PART TWO



31.6.2 entry into confined spaces

Tanks and other vessels may contain toxic gases and vapours from their previous use, or

residues which produce toxic or flammable vapours if heated, for example during cutting.

Water in a tank may have caused corrosion and a reduction of the level of oxygen in the

tank. It is essential, therefore, that any confined space is ventilated and the atmosphere

tested, before it is entered or any demolition work is permitted.

Entry to and work in confined spaces should be controlled by pre-planned “permit” systems

and backed up by a rescue procedure.

For further information on entry into Confined Spaces, (see Pt 2 section 21).

31.6.3 noise

Demolition plant, such as compressors and concrete breakers, frequently create noise

“levels” in excess of 100dB(A). Jobs likely to expose workers to an 8-hour noise dose above

90 dB(A) should be identified and arrangements made to ensure that ear muffs or plugs are

provided and worn.

Machines, were appropriate, should be marked with a prominent notice to warn that

operators should wear ear protection.

Ear protection must be suitable for the circumstances, supervision and training in its care

and use must be provided and there must be adequate facilities for its maintenance and

storage. Further guidance on Noise is given in Pt 2 section 3.

31.6.4 vibration

Pneumatic drills and breakers are among many hand held tools likely to give rise to vibration

white finger, particularly in cold weather. Keeping warm with waterproof and wind resistant

clothes and gloves, and restricting the time which individual workers operate such tools, can

reduce the risk of serious disability.

Plant and tools should be selected, as far as possible, to minimise the harmful effects of

vibration or jolting motions.

31.7 DEMOLITION TECHNIQUES

Demolition techniques may be categorised as:

• piecemeal demolition, using hand held tools, or machines, to reduce the height of the

building or structure gradually, or

• deliberate controlled collapse, demolition being completed at ground level.



PART TWO



31.7.1 piecemeal demolition by hand

Although only hand-held tools are used in this

technique, lifting appliances may be necessary to

hold larger structural members during cutting and

for lowering severed members and other debris.

Chutes should be used, where practicable, to

discharge debris into a vehicle or hopper. (see

Fig.2)

Parts of floors may be removed to allow the faIl of

debris, but access to those areas should be

effectively barred. Where access cannot be

prevented, guardrails should be fixed sufficiently far

back from the edges of openings to ensure

protection from falling debris.

Asbestos cement sheets should not be dropped or

unnecessarily damaged during hand demolition as

this could cause a health hazard; where possible,

sheets should be unbolted and safely stacked for

lowering to ground level.

Work on roofing sheets should be carried out from a

working platform, or crawling boards spanning the

purlins. In many cases, demolition of asbestos

cement sheeting may be achieved more effectively

by properly controlled machine methods, with a fan

of sprayed water onto the sheeting to control dust

emmission.

work on roofs.

A safe place of work must always be provided for hand demolition; the top of an unprotected

wall is not a safe place of work. Where scaffolding provides a working platform, it should

normally be dismantled progressively as the building is demolished, so that scaffold tubes

do not project mare than 3m above the work. Scaffold towers should not project above the

work more than one lift.

When scaffolding is tied to a building, additional ties may need to be provided at a lower

level before the upper ties are removed as the demolition proceeds. The working platform

should never be more than 6m above the highest row of ties. For further guidance on roof

work see Pt 2 section 32, and for use of scaffolding and mobile towers see Pt 2 section

29.

In all work on roofs, such as the recovery of second-hand tiles and slates, edge protection

must be provided where possible, or safety harnesses used.

FIG.2 - Example of a type of Rubbish Chute commonly used in both demolition and building operations.



PART TWO



steel framed buildings

Each main structural member, including roof trusses, should be supported by crane or

temporary props whilst the ends are unbolted or cut. Care should be taken due to the

possible springing of members when load restraining connections are removed. Structural

members and trusses should be carefully lowered to ground level.

Suitable working platforms, e.g. man-riding skips, must be provided for the cutting and

disconnecting of members at height. Existing structural steelwork is not normally suitable for

use as a working platform. Properly anchored safety harnesses should be used where

necessary.

Timber joists spanning the beams of steel framed buildings may be severed by chain saw.

Where material is allowed to drop to a lower level, the area below should be sealed to

prevent anyone entering.

31.7.2 piecemeal demolition by machine

Roof structures supported on wall plates should normally be demolished to wall plate level by

hand. Where the building to be demolished is attached to another structure, the two

properties should be separated by a minimum of 1m, using hand methods, before machine

demolition begins.

Only the machine operator and a trained banks man should be allowed within the restricted

area of 6m from the part of the building being demolished. The cabs of all machines should

be strong enough to protect the operator against the fall of debris; in particular the

windscreen and any roof light should be of shatterproof material and guarded by a grille of

steel bars or substantial steel mesh.

The following are the main demolition by machine methods:

balling

BaIling is normally carried out using a lattice jib

crane mounted on a drag-line crawler chassis.

The demolition ball, suspended from the lifting

rope and swung by the drag rope, should be fitted

with a steel anti-spin device. Balling is a skilled

operation and should be carried out only by

trained operators under the control of experienced

supervisors.

(see Fig. 3) showing photo of Crane using a

demolition ball, and (Fig.4) showing different types

of demolition balls used. FIG.3 - Crane fitted with Demolition Ball



PART TWO




• machines must be properly maintained and stand on firm, level ground.

• manufacturers should be consulted to establish any restrictions on the type or length of

jib, or the weight of the ball machines

• jib head should always be at least 3m above the part of the building being demolished,

but should be decreased as the height of the building is reduced.

• length of jib will also be determined by the need to avoid the underside of it striking any

part of the structure and for the angle of the jib not to exceed 60 degrees to the

horizontal, which might cause it to spring back over the cab.

• walls or columns may be demolished by swinging the ball in line with the stationary jib

using the drag rope.

• the ball should not be swung by slewing or derricking the jib.

• minimum effective weight of ball should be selected; a weight of one ton or less is often

adequate, and In order to reduce shock loading, ball may be suspended from a rubber

tyre shackled to the end of the hoist rope; in this case, a restraining chain must also be

fitted to ensure the ball cannot become detached in the event of tyre failure.

Where a crane is to be returned from demolition balling duties to lifting duties, it should first

be subjected to a thorough examination which should include:

• detailed inspection of the parts of the crane which may have been subject to damage or

deterioration during the balling operations.

• ropes and jib sections.

• rated capacity indicators and limiters.

Note: machines with fly jibs or telescopic booms should not be used.

Cylinderical Type Star Shape Type Pear Shape Type

Fig. 4 - Types of Demolition Balls common used for demolition purposes.



PART TWO



impact hammers

Impact hammers may have a track or wheeled mounted chasis with an articulated boom

which can be vibrated by hydraulic or pneumatic power and is fitted and used to walls or

columns in courses not greater than 600mm in depth. Steel reinforcement should be cut

separately as necessary.

hydraulic pusher arm

The hydraulically powered pusher arm, or pole, is normally mounted on a tracked or

wheeled chasis and has a toothed plate or hook for applying horizontal force to brick or

masonary wall. The machine should stand on a firm level base and apply force by a

controlled movement of pusher arm.

shears

Special attachments such as powerful

steel cutting shears of various capacities

can be fitted to certain hydraulic

excavators in place of the dipper arm.

Shears are particularly useful in cold

cutting of steel structures such as roof

trusses, thereby avoiding the need for

burners to work at height in dangerous

positions, and chemical plant where

stringent precaution would be required

for hot cutting work. (see Fig.5)

31.7.3 deliberate controlled collapse

Buildings normally have structural elements designed to safely carry the loading likely to be

imposed.

Prior to a deliberate controlled collapse, after loads such as furnishings, plant and machinery

have been removed, it may be possible to weaken some structural elements and remove

those which have become redundant. This pre weakening must be carefully planned and

take into account the ability of the remaining elements to resist wind or impact loads until the

intended deliberate collapse. The indiscriminate cutting of steel members until the structure

collapses (“Cut and run”), is highly dangerous.

Steel structural elements are normally pre weakened by cutting, wholly or partially, through

the section, with a gas torch or thermic lance. For small sections, a cutting disc may be used.

A variety of different types of cut may be used to suit the planned method of collapse.

Brick or masonry buildings may be pre weakened by cutting rectangular or triangular

openings at predetermined positions around the base, using hand tools, hand-held vibrating

picks or machine-mounted pneumatic hammers. Further weakening can be achieved by

FIG.5 - Heavy duty Shears fitted to a Tracked Excavator



PART TWO



removing selected internal walls and floors where they join external walls.

Reinforced concrete walls may be similarly pre weakened by breaking out the concrete along

the outline of the required opening and cutting away the exposed steel. Selected concrete

columns may be removed completely, or weakened by exposing some of the reinforcing

bars,

31.7.4 overturning / wire rope pulling

Deliberate controlled collapse may also be induced by the application of a horizontal force at

high level. The structure is pulled with wire ropes attached to winches or vehicles, demolition

being achieved by impact on overturning.

Ropes should be attached to the structure before pre weakening is carried out; mobile work

platforms, or other suitable equipment, may be needed to gain access, and be in good

condition and not less than 38mm circumference

When used with winches of sufficient rope capacity and tractive effort, an adequate steel cab

or cage should protect the winch or vehicle operator which should be at a minimum distance

from the building of one and a half times its height, or twice the height where parts of the tap

of the structure may separate.

Unsuccessful attempts to pull over a building or structure may render it unstable or

dangerous to approach, therefore, an alternative method of work must then be used.

Note: Brick or masonry buildings over 21m high should not be demolished by rope pulling.

31.8 SAFETY PRECAUTIONS FOR SPECIAL STRUCTURES

Certain types of structure present particular problems, requiring more detailed research in

selecting a method of work and more specific precautions than those outlined in the

foregoing paragraphs.

Examples of some of these problems are given below:-

prestressed concrete

A pre stressed concrete component has pre compression applied by steel wire, cables or

threaded bars tensioned to counteract the tensile forces induced by the working load.

Special precautions are necessary in demolition as it is dangerous to allow uncontrolled

release of the potential energy stored in the tensile elements.

Demolition of a pre stressed concrete structure should be under the supervision of an

engineer who understands the construction principles and is experienced in the demolition of

more conventional structures.



PART TWO



chimneys

When a chimney is demolished by hand, debris may be dropped down the inside and

cleared at intervals through a narrow opening cut at ground level. Where practicable, a

working platform complying with the requirements in Pt 2 section 29 must be provided and

used.

If provision of such a working platform is not practicable, personal suspension equipment

(i.e. bosun’s chairs or abseiling equipment) must also be provided and used.

31.9 TRAINING AND COMPETENCE

The inherent risks and dangers involved in the demolition industry is well known. It is therefore

of the utmost importance that those who plan and manage the demolition project, together

with those who carry out the demolition work receive adequate training in all aspects of the

work

Training should cover, but not be limited to the following:-

• Relevant Ministerial Orders

• Accident prevention

• Personal protection

• Asbestos and lead

• Electricity (on site)

• Fire

• Noise

• Oxygen/fuel gas cutting

• Emergency first aid

• Fitting of abrasive wheel

SAFETY CHECKLIST - DEMOLITION


ADM/H&S/CL/2.31/1 01 March 2005 SAFETY CHECKLIST - DEMOLITION 1 of 1

CHECKLIST FOR DEMOLITION METHOD STATEMENTS

�� Name and address of the demolition contractor.


�� Names of the supervisor/foreman and appointed safety adviser and details for monitoring the

work.

�� Description of the works to be carried out.

�� Details of the personnel to be used and their training/ experience.

�� Details of PPE to be provided to personnel.

�� Details of any scaffolding required including name of scaffolding firm, details of Municipality

Licenses required.

�� Arrangements for statutory inspections

�� Arrangements for progressive dismantling.

�� Arrangements for the removal of demolition waste

�� Assessment of existing services with arrangements for making them safe.

�� Temporary services available or required.

�� The sequence, programme and working hours.

�� The way in which the work will be carried out safely.

�� How safe access/egress and a safe place of work will be provided for each operation.

�� Edge protection at stairwells, lift shafts and external floor edges.

�� Plant and machinery to be used.

�� Details of any temporary support required.

�� Arrangements for the protection of the public.

�� Arrangements for storage/use of LPG and compressed gases.

�� Assessments of hazardous substances e.g. asbestos, chemicals, lead paint, abandoned

materials etc.

�� Welfare facilities provided.

�� Environmental considerations e.g. noise, dust, vibration, crushing plant.

Note



SECTION 32

SECTION 32

SAFE WORKING ON ROOFS

INTRODUCTION 1


32.1 ACCESS AND WORKING PLATFORMS 2

32.2 ROOF WORK (GENERAL) 3

32.3 WORKING ON OR NEAR FRAGILE ROOFING MATERIALS 5

32.4 METHOD STATEMENT 5

32.5 ADDITIONAL SAFETY PRECAUTIONS REQUIRED 6

32.6 PROTECTION OF THE PUBLIC 6

CHECKLIST FOR PRODUCING METHOD STATEMENT AND WORKING ON

FRAGILE ROOFS

(ADM/HSE/CL/2.32/1)



PART TWO


ADM/H&S/Pt 2 01 March 2005 SAFE WORKING ON ROOFS 1 of 6

SECTION 32

SAFE WORKING ON ROOFS

INTRODUCTION

Working on a roof can be dangerous. Falls account for more deaths and serious injuries in

construction than anything else. Nearly half of them are from or through roofs and frequently involve

fragile materials. Any fall from a roof inevitably involves serious injuries.

The risks are substantial however long or short the work. Many have been killed who only meant to be

on the roof for a few minutes ‘to have a quick look’.

The information in this section is aimed at people who actually carry out roof work or are directly

responsible for managing or supervising it, and sets out key safeguards

falls occur:

• from the edges of roofs

• through gaps or holes in roofs

• through fragile roof materials and roof lights

In addition, many people have been seriously injured by material falling or thrown from roofs.

Accidents occur not only to those building roofs, but also to people maintaining, cleaning, demolishing

and inspecting them.

Any work on a roof is high risk. High safety standards are essential however long or short term the

work is. The nature of the precautions needed may vary from one job to another, but not providing any

safeguards is simply unacceptable.


Ministerial Order No. (32) Year 1982 - Article (7) H



PART TWO



32.1 ACCESS AND WORKING PLATFORMS

32.1.1 roof edge protection

Where persons or materials are liable to fall more than 2 meters or there are roof edges or

where work is over water, liquid or dangerous materials, edge protection must be provided.

(see Fig.1, 2 & 3) showing typical type of edge protection required for both sloping and flat

roofs.

Guard Rail

Intermediate Rail

Scaffold Board

Fig.1 - Scaffold Supported from Window Opening.

Max. Gap

910mm.

To raise the line of the roof slope with a min. height of 150mm.

Gap between rails no

more than 470mm.

Max 910mm.

Fig 2 - Working Platform below the eaves – Dimensions to be as indicated above.

Fig.3 – Flat Roof edge Protection: Proprietary Counterweight System. This system allows one of the counterweight to be removed, and the base plate raised to enable work at edge to continue unhindered while guard rail remains in position.

Counterweight removed and base plate fitted.



PART TWO



32.1.2 openings in roofs

• all holes in roofs must be guarded or

securely covered. The covering must be of a

suitable material, securely fixed and clearly

marked 'Hole below'. (see Fig.4)

• open joists through which a man could fall

more than 2 meters must be boarded over

and secured to provide safe access to a

working place.

exemptions

Guard rails toe boards and covers may be removed to allow access for men and materials,

but must be replaced as soon as possible. This does not apply to demolition work unless

it is left unattended.

32.2 ROOF WORK (GENERAL)

32.2.1 flat roofs

A roof having a pitch of less than 10 degrees is classed as a flat roof. Safe access to the

roof must be provided and maintained.

If there is no parapet or similar barrier against falling, edge protection must be provided. This

may take the form of standard guard rails and toe board or, providing nobody will approach

the edge of a barrier, set back from the edge.,

Where work on the leading edge is actually in progress, guard rails may be removed or left

off, subject to the requirements that:

• a safe system of working which prevents falls is maintained.

• barriers are erected or re-erected as soon as the work ceases.

32.2.2 sloping roofs

A sloping roof is defined as any roof having a pitch of more than 10 degrees.

Work on a sloping roof with a pitch of more than 30 degrees or between 10 degrees and 30

degrees if slippery, should:

• only be done by those who are physically capable.

• be done using crawling ladders or boards which must be securely fixed to prevent

slipping.

Fig.4 - Showing type of cover and signage used to protect openings in roofs.



PART TWO



• employ either a suitable catch barrier or platform erected at the eaves, or a two board

430mm wide working platform with guard rails.

Note: this applies to any work on a sloping roof including access and egress to other work

places.

32.2.3 steep roofs

If the steepness of the roof is such as to prevent a secure foothold, a working platform will be

required. Roofs pitched at over 50 degrees should be regarded as 'steep' as should be

shallower slopes if they are slippery (see Figs. 5 & 6) which shows the use of crawling

boards and roof ladders to cater for both sloping and very steep roofs.

32.2.4 curved roofs

Short sections of ladders or crawling boards should be used so that the shape of the roof is

closely followed and only the shortest length of ladder or board is left unsupported at any

point. Sections must be fastened together and securely anchored. On some shaped roofs,

traditional tube and fitting scaffolding may be the only means of following the roof contours.

crawling ladders/boards must:

• be of good construction, strong enough and properly maintained.

• properly supported

• securely fixed to the sloping part of the roof over the ridge. Ridge hooks must not bear

on ridge tiles or capping tiles.

If the spacing of the battens is greater than 400mm and persons could fall through, roof

ladders or crawling boards must be used.

Fig.5 - Showing roof ladder fitted with wheels–to facilitate the ladder being placed in position over roof ridge.

Fig.6 - Showing ridge and hip irons which should be of sufficient size so that when in position, they are clear of the ridge and tiles.

Ridge Iron.

Hip Iron.



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32.3 WORKING ON OR NEAR FRAGILE ROOFING MATERIALS

Fragile roofing materials include glass, plastic, cement sheet and other similar brittle

surfaces.

Substantial - looking roof cladding can be dangerously corroded. Surface coatings or dirt

may conceal the fragile nature of the material, giving an appearance of solidity to glass,

plastic, etc.

When working on or passing across fragile roofing materials, crawling boards must be used

so that the workman's weight is on the board, never on the fragile roof sheeting, various

plastic materials are particularly brittle and shatter without warning. At least two crawling

boards should be used, one to support the workman while the other is moved to a new

position.

The practice of trying to 'walk the line of the bolts' is dangerous and akin to walking a tight

rope. Where walkways are not provided, a safe system of work such as that described

above must be employed.

Work involving the handling of sheeting and cladding requires extra care in windy conditions,

when a sheet may act like a 'sail' - causing the person holding it to lose balance.

32.3.1 walkways

Valleys, parapets, gutters or channels etc. where access is

required, must be provided with suitable guardrails or the

fragile material should be suitably covered to prevent any

possibility of anyone falling through,

32.3.2 warning notices

Must be fixed at all approaches to roofs constructed with

fragile materials. (see Fig.7)

32.4 METHOD STATEMENTS

It is always good practice to produce a method statement prior to carrying out any roof work

in order to establish both the type and condition of the roof that you will have to work from,

and the precautions necessary for safe working.

(A general check list for working on roofs, also for producing a method statement for

working on fragile roofs can be found at the end of this section)

Fig. 7 – Approved sign for identifying fragile roofs



PART TWO



32.5 ADDITIONAL SAFETY PRECAUTIONS REQUIRED

32.5.1 safety nets

If safety nets are used, make sure that they are properly installed by competent riggers as

close as possible below the roof involved to minimise the distance fallen.

Installing a net does not mean that proper working platforms and edge protection can be

ignored, because the first priority is to stop people falling.

Further details on the provisions of safety nets can be found in (see Pt 2 section 29).-

Scaffolds and Working Platforms.

32.5.2 safety harnesses &safety belts

If harnesses/safety belts are used, make sure that they securely attached to a sufficiently

strong anchorage point and that they are also worn. This requires user discipline and active

management monitoring.

Further details re types of harnesses and belts available can be found in (see Pt 2

Section 12) - PPE, and details regarding safe anchoring points etc. can be found in (see Pt

2 Section 30). –Erection of Structures.

32.5.3 scaffolding & working platforms

In addition to the provision of edge protection for roof work, it will also be necessary to

provide access onto roof via ladders, mobile scaffold platforms or independent type scaffold.

Further details re the safe use of ladders, mobile and independent scaffolds can be found in

(see Pt 2 section 29). – Scaffolds and Working Platforms.

32.6 PROTECTION OF THE PUBLIC

Members of the public must be protected from the hazards of any falling material during roof

work operations. This may entail the provision of brick guards, fans or other similar

precautions.

It may also be necessary to lay sheeting or boarding to prevent material falling through gaps

in the working platform, or between working platform and the building.

Barriers at ground level may also be necessary.

SAFETY CHECKLIST - WORKING ON ROOFS


ADM/H&S/CL/2.32/1 01 March 2005 SAFETY CHECKLIST - WORKING ON ROOFS 1 of 1

PREPARING METHOD STATEMENTS FOR WORKING ON BOTH NORMAL AND

FRAGILE ROOFS

�� Name and address of contractor involved.

�� Name and address of site to which method statement relates.

�� Description of fragile materials and their location.

�� Means of access/egress to/from the roof or other workplace.

�� Means of protecting fragile materials which persons work near or pass close to.

�� Arrangement for providing safe access across fragile materials.

�� Arrangements for protection against falls from the edge of the roof and other workplaces.

�� Do the roof battens provide safe hand and foot holds? If not, are crawling ladders or boards provided and used?

�� Are suitable barriers, guard rails or covers, etc provided where people pass or work near fragile material such as glass. Plastic and roof lights?

�� Are people excluded from the area below the roof work? If this is not possible, have additional precautions been taken to stop debris falling onto them?

�� Details of any hazardous substances and arrangements for safe working and disposal of waste.

Note:

This checklist is intended to aid the production, and approval of method statements. It is not

an exhaustive list of every possible issue that may need to be addressed for any given task.

SECTION 33

SECTION 33

REFURBISHMENT

INTRODUCTION 1


33.1 PLANNING 2

33.2 PRE TENDER HEALTH AND SAFETY PLAN 2

33.3 STORAGE 3

33.4 WELFARE FACILITIES 3

33.5 ACCESS 3

33.6 SCAFFOLDING AND ROFWORK 4

33.7 TEMPORARY WORKS 4

33.8 WORKING IN PARTIALLY OCCUPIED BUILDINGS

AND ADJACENT TO THE GENERAL PUBLIC 5

33.9 SERVICES 6

33.10 LIFTS 6

33.11 RUBBISH CHUTES 6



PART TWO


ADM/H&S/Pt 2 01 March 2005 REFURBISHMENT 1 of 6

SECTION 33

REFURBISHMENT

INTRODUCTION.

The refurbishment of buildings can be complex whatever the age of the building. In older buildings, all

or part of the building, may be the subject of strict control under Planning Legislation.

Very detailed preparation and planning will be necessary where extensive shoring-up operations are

to be carried out and professional advice from a structural engineer or a surveyor should be obtained

before any structural members are removed.

Temporary supports will invariably be required, or loads transferred to other areas to avoid an

unplanned collapse.

Buildings being refurbished may be located between, or form part of a complex of other buildings

which must not be disturbed. This creates additional problems relating to the space available and the

possibility of nuisance to occupiers. Every effort must be made to establish good working relationships

with existing occupiers and neighbours.

Many more contemporary buildings are now reaching a stage where major refurbishment is

contemplated. This is particularly relevant in the case of commercial buildings where work patterns

have changed and the provision of extensive services is seen as a particular need. Many of these

buildings were speculatively built and little, if any, detailed record of their construction exists. Great

care is therefore needed in planning the work. There are often hidden dangers in their construction

that need to be thoroughly investigated at an early stage.


Ministerial Order No. (32) Year 1982 - Articles 7, 9, 17 & 20



PART TWO



33.1 PLANNING

The primary rule in planning the refurbishment of old buildings is that the fabric of the

building cannot be assumed to be sound. In addition to the likely differences from modern

construction, it must be realised that maintenance work and previous refurbishment may

have been carried out over the years.

Assumptions should not be made regarding the load bearing elements of the structure and

in particular supporting members e.g. joists, since these may have been replaced in a

completely different format to the original structure. Planning will invariably be much more

complex than is the case with a new construction.

33.2 PRE TENDER HEALTH AND SAFETY PLAN

The owner/client should ensure that as much information as possible about the building and

type of construction is provided to the contractor. This information, together with details of

hazards identified by surveys carried out on behalf of the client (e.g. for asbestos) should be

included in the pre-tender health and safety plan, which the consultant has to ensure, is

prepared. The pre-tender health and safety plan should contain sufficient information to

enable a prospective contractor to be aware of the likely hazards before tendering for the

work.

Work should not start until an in depth survey has been carried out to determine the real

extent of deterioration and other hidden hazards which may not be known at the tender

stage. The building fabric may have been covered by plaster, panelling, floor coverings etc.

The need for further demolition and remedial work due to damp, dry rot, presence of

asbestos, etc. may only become apparent as work progresses. The health and safety plan

will therefore need to be reviewed and updated at each stage of the work after close

consultation between the principal contractor, designers and other contractors. The planning

supervisor must be advised of these changes.

Each aspect of the refurbishment work needs to be carefully planned and detailed method

statements produced where appropriate. It is particularly important that any demolition

should be covered by a method statement which takes into account the integrity of the

remainder of the building, any temporary works required and a checking or monitoring

system for the falsework before demolition takes place.

The health and safety plan should also co-ordinate all aspects of the work in order to

achieve a correct sequence of operations. Plant and equipment must be positioned in its

correct place, especially since space may be limited and access may not be ideal.



PART TWO



33.3 STORAGE

Storage facilities are usually very restricted. However; adequate and proper facilities must be

provided for the storage of items such as highly flammable liquids and LPG which are a

potential fire hazard Preplanning of the storage areas, together with the provision of

appropriate Floor loading notices, is necessary at the start of the contract. Where necessary,

materials should be stored off site and only the minimum quantities called in as required.

Adequate and suitable fire fighting equipment must be provided and supervisors must be

made aware of the dangers of carelessly stored materials or overloaded floors, resulting

from the accumulation of debris or temporary loads.

33.4 WELFARE FACILITIES

It is important that good welfare facilities are provided, even where space is limited. It will

often be necessary to give considerable thought to the provision and siting of these facilities

(see Pt 1 section 6) - Setting Up Site.

33.5 ACCESS

In many situations, there is only limited access to the site, particularly in congested town and

city areas. It is essential, at tendering stage, to investigate the means of access required

during the contract and the provisions to be made for the unloading of materials, plant and

equipment and the removal of rubbish.

In particular the safety of the public, occupiers, and any adjacent occupiers needs to be

considered, also allowance must be made for any fans, hoardings, safety netting or gantries

required.

Safe access from floor to floor is paramount during the course of the works. If the building

has only a single staircase access to upper floors and this is to be replaced or repositioned,

then consideration needs to be given to its provision or repositioning as a first priority.

A ladder access tower should be erected as a temporary measure only. If this cannot be

achieved then a temporary external scaffold staircase should be provided particularly where

the existing staircase is suspect as to strength.

Consideration should also be given to the provision of a passenger/goods hoist where there

are more than three floor levels.



PART TWO



33.6 SCAFFOLDING AND ROOFWORK

Scaffolding requirements are different for refurbishment work. The main structure is already

in existence, so scaffolding for roof works and external repairs and decoration is normally

taken immediately up to roof level, and work is then carried out from the top downwards.

On contracts where major roof works are required, it may be necessary to install a

temporary roof, with or without side sheeting. This decision has to be made at an early

stage, preferably prior to tendering and the scaffold designed to take the roof loads, wind

loads etc. Specialist advice should be sought for all but the simplest of structures.

Further, there are difficulties in tying the scaffold into a possibly unsound structure.

Moveable ties (through reveal, or box ties) rely on the strength of the structure for their

security. Where non-movable ties (e.g. drilled anchors) are to be used in unreliable material,

it is essential that tests are carried out as recommended by the anchor manufacturer.

In order to ensure a sound tie, it may be necessary to connect the front and rear elevations

of scaffold right through the building. Further guidance on ties and scaffolding in general, is

given in (see Pt 2 section 29). – Scaffolding.

33.7 TEMPORARY WORKS

It is always necessary to do a certain amount of cutting of new openings and generally

convert the existing structure. If this is done without careful planning and supervision, a

dangerous situation can easily arise. If the main load bearing walls are to be removed or

radically altered, there will be a need for supporting formwork.

Unlike formwork in most building contracts, the major problem with refurbishing is where to

transmit a load to an adequate support. It is absolutely vital that the foundation aspects are

dealt with as a priority item and completed prior to alterations to the main structure.

It is also essential for each situation to be carefully assessed and all formwork designed by a

competent person. Any underpinning and foundation works must be conducted under the

supervision of an experienced structural engineer; as the imposed loads can be quite

deceptive in older buildings. A temporary works co-ordinator may be essential in this type of

work.

For further information on formwork – (see Pt 2 section 25). – Falsework.



PART TWO



33.8 WORKING IN PARTIALLY OCCUPIED BUILDINGS AND ADJACENT TO

THE GENERAL PUBLIC

Working in partially occupied buildings and adjacent to the general public calls for particular

care, and special precautions need to be taken to protect the occupants and visitors. Their

means of access and escape must always be maintained and additional temporary

measures may be necessary. Measures must also be taken to protect them against falls,

falling materials, dust, vibration, fumes and other hazards.

33.8.1 fire alarm systems

fire alarm system must be maintained, although part of a smoke/heat detection system may

have to be temporarily disconnected when hot work such as burning or welding operations

are carried out; a hot work permit system should be laid down for such work. All planning

should be carried out in close liaison with the building occupier and, where appropriate, the

local fire authority.

33.8.2 inspection of services

the need for services to be inspected before commencement of work is particularly important

when dealing with partially occupied buildings. Arrangements must be made before the

starting date to ensure that services to the occupied section are not attached and that the

power supply is adequate to cope with both the needs of the contractor and the remainder of

the building.

Consideration should be given to fitting residual current earth leakage circuit breakers on

services which may be damaged by contractors’ activity.

During refurbishment it is sometimes necessary to enhance services to meet modern

information technology and environmental requirements. This can entail breaching fire

stopping in services, recesses, ducts and voids where fire can spread rapidly.

Wherever possible, temporary fire stopping should be provided as work proceeds, and at the

end of each day's work. Care should be taken that occupants are not put at risk during such

work.

33.8.3 welfare facilities

it is important to maintain welfare facilities to both sections. For example, if the drainage is to

be renewed, the work must be carried out in such a way as to leave the drainage to the

occupied section still working satisfactorily. The same applies to gas, electricity and water

supplies.

33.8.4 noise

there can also be major problems with noise levels and vibration which affect not only the

workers, but also other persons and their employees during office or opening hours,

depending on the use of the buildings, and the hours being worked. In such cases, planning

needs to be directed towards noise-reduced compressors and other machinery, in order to



PART TWO



minimise the inconvenience.

Where noise levels are written into the conditions of contract, it will be necessary to carry out

a noise monitoring exercise to ensure compliance and to satisfy the occupants of the

building or adjacent buildings that the contractor has treated the matter seriously.

33.9 SERVICES

In all refurbishment contracts, especially where buildings have been left empty, all services

must be checked carefully, particularly electricity and gas since any persons temporarily

occupying these premises may have illegally reconnected services, often in a dangerous

manner. Where any suspect installation is found, the appropriate authorities must be

contacted to eliminate any faults.

It is often a wise precaution to have temporary supplies provided but, before this is done, all

existing services should be identified. Where existing services are to remain live, their

positions must be located and clearly marked.

On a larger type of refurbishing contract, the installation of a temporary supply is very similar

to that on any building contract. The only difference is that, in refurbishing as the structure

already exists, most of the temporary supply is required to be put in at the beginning. The

lighting must be of the right type and in the right place (e.g. stairs must be well lit) and

waterproof lampholders provided if moisture is present inside the building, or if rain can

penetrate. Tungsten filament lamps should always be protected by guards or shades.

For further information electricity – (see Pt 2 section 7) – Electricity at Work.

33.10 LIFTS

Refurbishment in large buildings sometimes necessitates use of passenger lifts for transfer

of building materials. Copies of thorough examination certificates should be obtained; it may

be necessary to increase the frequency of inspection and examinations to take account of

heavy usage.

33.11 RUBBISH CHUTES

The disposal of non-hazardous waste can be a problem in refurbishment. Materials must not

be thrown down and rubbish chutes should be used, where possible. Properly installed and

used, a rubbish chute, with a hopper at the upper end and a skip at ground level, provides a

safe method of conveying surplus materials from considerable heights with minimal risk.

Chutes may be attached directly to a building, or to a scaffold and often have branched

connections at different working levels. Sections are raised and lowered by means of a

winch, rope or crane and most designs rely on gear such as U-bolts, eyebolts, chains and

shackles, etc. for suspension and the attachment of one section to another.

SECTION 34

SECTION 34

MAINTENANCE

INTRODUCTION 1


34.1 MAIN HAZARDS 2

34.2 PLANNING 2

34.3 PRELIMINARY SURVEY 2

34.4 CONDITION OF STRUCTURE 3

34.5 EXISTING SERVICES 3

34.6 MACHINERY 4

34.7 TOXIC SUBSTANCES 4

34.8 PERSONS NOT EMPLOYED IN MAINTENANCE WORK 5

34.9 STORAGE 6

34.10 ACCESS AND WORKING PLACES 6

34.11 WORKING PLACES (GENERAL) 7

34.12 PLANT 8

34.13 SCAFFOLDS 9

34.14 DEBRIS 10

34.15 HEALTH HAZARDS 11

34.16 TOOLS AND EQUIPMENT 11

34.17 ROOFS 11

34.18 PROTECTIVE CLOTHING AND EQUIPMENT 11

34.19 MAINTENANCE PERSONNEL 12



PART TWO


ADM/H&S/Pt 2 01 March 2005 MAINTENANCE 1 of 12

SECTION 34

MAINTENANCE

INTRODUCTION

Maintenance work is dangerous. Around 40% of all fatal accidents on building operations occur during

maintenance; yet the seriousness of the problem is too often underestimated by management, safety

advisers and operatives because the jobs are usually relatively simple, and of short duration.

Many of these accidents could be prevented by the properly planned implementation of well

understood precautions, so there is clearly considerable scope for reducing their number - but this will

only happen if there is a drastic change in industry’s approach to maintenance work.

Preparing guidance on maintenance safety is difficult because so many different trades are involved,

all with their own distinctive hazards, while at the same time, the individual trades encounter some

common problems when engaged in maintenance work.

Detailed guidance on the risks and precautions in individual sectors will be found in other sections of

the manual. This section highlights the factors which create special risks during maintenance, looks

briefly at the accident background and draws together the most important lessons from other sections

of the manual and from other sources.


Ministerial Order No. (32) Year 1982 – Articles 5, 7 & 9



PART TWO



34.1 MAIN HAZARDS

Some of the important factors which influence attitudes to maintenance and produce the

distinctive hazards associated with the work are:

• the short duration of much of the work, which can encourage the use of the least time-

consuming and least safe means of access,

• its repetitive nature, which breeds complacency about the risks and contempt for safety

procedures and precautions,

• the difficulties in supervising and monitoring small mobile groups working away from their

base,

• the deterioration in the structure, or the disguising of its fragile nature after years of use,

• the building often remains in use, creating problems for the maintenance workers, and

risks to the occupants.

34.2 PLANNING

In view of the high level of risk likely to be involved in maintenance, it is essential for the

work to be properly planned. Planning should include:

• ensuring that all relevant information on the building and on activities within it is provided

by the occupier or client,

• carrying out a preliminary survey to identify the type of structure, the range of

maintenance work required and the hazards likely to be encountered,

• preparing safe systems of work to eliminate or reduce the risks from identified hazards,

• where work is to be carried out in occupied premises, ensuring adequate arrangements

for the health and safety of occupiers,

• ensuring that employees are adequately instructed, trained and supervised.

Identified hazards should be included in the pre-tender health and safety plan which the

consultant must ensure is prepared. Relevant safety precautions and procedures should be

included in the construction phase health and safety plan which the main contractor must

ensure has been sufficiently developed before the work is carried out.

34.3 PRELIMINARY SURVEY

Many hazards encountered in building maintenance will arise not only as a result of the work

itself, but from the condition of the structure, the proximity of live services, the presence of

toxic materials or the necessity to work in locations where there are persons not employed in

maintenance work, i.e. employees of other employers or the occupier, or the general public.



PART TWO



In addition, work may be carried out close to machinery which is continuing to be operated. It

is therefore essential that, prior to detailed planning of working procedures, a thorough

survey of the building and its contents is implemented by persons whose experience and

training will enable them to identify such circumstances which may give rise to risks during

the maintenance.

Note should also be taken of any safety rules imposed by the occupier, with which

maintenance workers must comply.

34.4 CONDITION OF STRUCTURE

The physical condition of the structure of the building must be investigated to determine the

presence and condition of:

• fragile roofs including any gutters which may be required to be used either as a working

place or as a means of access. Asbestos-cement roofs for instance, should always be

treated as fragile and materials such as corrugated metal decking should be examined

for deterioration due to prolonged exposure to the elements or corrosion from processes

within the building..

• floor joists and roof trusses which may be required to support scaffolds, falsework, plant

and materials or any other load hitherto not imposed on those members.

• walls which may be required to accept scaffold ties or fixings for safety nets or

harnesses. Where the strength of the wall is in doubt, then further investigation may be

required by a Structural Engineer.

• existing facilities for access and working places.

Note:

Maintenance work may involve the use of permanent equipment which has not been used

for many years, and any such permanent metal access ladders, gantries, safety harness

anchorages, etc., should be thoroughly inspected and where necessary, tested before any

assumption is made that they may be used in the maintenance operation.

34.5 EXISTING SERVICES

All existing services must be located and their routes traced, marked and recorded. These

will include electrical, gas, water, air lines, fuel lines, both liquid and gaseous, any supply

lines required for processes within the building and any extraction or exhaust equipment

carrying toxic or otherwise hazardous substances. (see Pt 2 section 6) – Overhead and

Underground Services.



PART TWO



Where there is any risk of damage to any of the services arising from the maintenance

operation, every attempt must be made to isolate them prior to the commencement of the

work.

Any such isolation procedures must be controlled by a formal “Permit to Work” system

incorporating the use of “lock off” devices with the key in the possession of the person

carrying out the maintenance. If it is necessary to maintain the services, then isolation may

still be achieved by diverting the supply away from the area where the work is to be carried

out. (see Pt 2 section 11) – Permit to Work.

34.6 MACHINERY

When persons are required to work in elevated positions then they may be in close proximity

to dangerous parts of moving machines which would otherwise be safe by position. In such

cases, the machines must be locked off with the maintenance operator holding the key, and

the activity controlled by a “Permit to Work” system.

Where it is necessary to keep any such machine working, then the maintenance should be

re-scheduled to a time when it is possible to close the machine down or, alternatively,

protective screens must be erected to prevent the risk of contact with the dangerous parts.

Erection of such screening would take place with the machine locked off under a “Permit to

Work” system. Particular attention should be given to the situation where persons are

required to work on or near the wheel track of an overhead travelling crane, or any other

position where he can be struck by a part of that crane.

The crane should either be locked off or have stops fitted to the rail to ensure that the crane

does not approach within 6.0m of that person.

34.7 TOXIC SUBSTANCES

34.7.1 asbestos

The survey must take account of work which may give rise to the presence of dust and

fumes, paying particular attention to asbestos. It is necessary to establish the type of

asbestos which may be encountered. Unless this is known, samples of the asbestos must

be analysed to determine the nature and concentrations involved. (See Pt 2 section 5) –

Substances Hazardous to Health.

34.7.2 lead

Particular attention should be paid to steelwork which has been coated with lead based

paint. If such steel is to be burned, wire brushed, ground, etc., then samples of paint must be

taken to establish the lead content. Control measures or personal protection will be required

in accordance with (See Pt 2 section 5) – Substances Hazardous to Health.



PART TWO



34.8 EFFECTS OF MAINTENANCE WORK ON PERSONS OTHER THAN

THOSE EMPLOYED

Maintenance work may give rise to other persons, such as when work is carried out above

members of the general public or building occupiers or if materials and debris are deposited

in such a way that access routes are being impeded.

Serious consideration must therefore be given to the adverse effects which maintenance

work may have on persons not employed, particularly where domestic premises and public

places to which children, the elderly and the blind or otherwise handicapped persons have

access. For example:

34.8.1 public highways

Where it is necessary to obstruct any public highway, including footpaths, for the purpose of

depositing material, erecting scaffolds, etc., then the requirements of Abu Dhabi Municipality

Traffic Section.

34.8.2 access routes

Care should be taken to ensure that plant and material do not impede pedestrian and

vehicular accesses without prior permission of the building occupier who may be able to

make alternative arrangements. To this end, good housekeeping is of utmost importance. It

will be necessary to investigate fire escape routes in all circumstances where they may be

obstructed by maintenance activity and to ensure that such work will not delay evacuation in

the case of fire. This may involve designing scaffolds in corridors and stairwells so that

accesses are not obstructed.

34.8.3 maintenance plant

In many cases the use of traditional construction plant may not be suitable for maintenance

operations. High noise levels from pneumatic breakers could place building occupiers at risk

as could exhaust fumes from dumpers, hoists, etc.

34.8.4 overhead work

Maintenance operations are often carried out above areas normally accessed by the public

or building occupiers.

If exclusion zones cannot be established below such work then it is imperative that adequate

protection is provided to ensure that tools, material, debris, etc. cannot fall. This can be

achieved by the use of fans, by meshing the face of the scaffolds, by boarding below

platform level or by slinging debris nets.

If the maintenance involves such operations as breaking out brickwork, painting or other

work where falling particles would be extremely small, then sheeting should be used instead

of nets, bearing in mind the additional wind loading this may impose on a scaffold.

If welding or burning is to be carried out then the protection must be non-combustible and it

may be necessary to provide welding screens to protect persons from the effect of welding

flash.



PART TWO



34.9 STORAGE

Before bringing plant and materials to the site of maintenance operations, careful

consideration must be given to storage facility.

Care must be taken to establish areas which do not give rise to obstructed access either to

the occupiers of the building or to persons engaged in maintenance work. It should be noted

that the storage of traditional building materials such as timber, due to its flammability, or

hazardous chemicals, due to their interaction with processes carried out within the building

or arising out of the proximity of the storage areas with fire escape routes, may give rise to

risks to safety and health. In order to minimise such risks, it is important that close liaison

exists between persons carrying out the maintenance work and the persons in control of

processes within the building.

34.10 SAFE MEANS OF ACCESS

The introduction to this section identifies the inadequacy of access as giving rise to the

majority of accidents associated with maintenance work.

This is often due to the short duration of a particular operation and the fact that no suitable

form of access or working place exists

The high accident frequencies highlight the need for a serious commitment to the provision,

inspection and maintenance of places of work together with the routes used to gain access

to them.

It may be possible to use permanent accesses and gantries etc. within a building, but they

must be checked for their suitability for the passage of persons and material. Where any

such facility has not been used for some time they should be checked for deterioration,

paying particular attention to the integrity of decking and any handrails and their points of

attachment to the structure.

lighting

many accesses and working places used in maintenance operations will be in areas not

served by the permanent lighting within the building and will have to be provided with

temporary lighting as described in (see Pt 2 section 7) – Electricity at Work.

ladders

these are the most commonly used means of access to an elevated working place. Ladders

are also widely used as working places but this should be allowed only after careful

consideration that it is safe to do so. This will depend on the type and duration of the work

and on the security of the ladder.

full guidance on the safe use of ladders is given in (see Pt 2 section 29) -Scaffolding, but

the following criteria are particularly relevant to maintenance work:

• ladders must be inspected prior to their use, and those with missing or damaged rungs or



PART TWO



damaged stiles must not be used.

• home-made ladders must not be used.

• ladders must be set at a working angle of approximately 75°, i.e. 4 units vertical to I

horizontal (unless fixed to the side of a scaffold tower; when they will be fixed vertically).

• ladder stiles should normally rest on a firm level base. If it is intended to rest the ladder

on an uneven base or stairway, etc. then a levelling device must be fixed to the lower end

of the stile or stiles to ensure that the ladder is supported evenly. Bricks, blocks of wood,

etc. must not be used to pack up stiles an uneven ground.

• where possible, ladders must be secured near the upper resting point by both stiles. In

certain cases, the use of spreader arms attached to the top of the ladder may satisfy this

requirement, but it must first be established that the ladder; so fitted, cannot slip in the

circumstances in which it is used..

• ladders must be placed so that there is a clear space behind each rung to permit the

secure placing of a person’s feet.

• suitable access to a working place must be provided at the stepping off point. Persons

must not be required to climb aver or through guardrails and toe boards. Gaps in

toeboards and guardrails must, however; be kept as small as possible.

• single board runs to ladders must not be used.

• only one person should be permitted on a ladder at any one time.

34.10.3 step ladders and trestles

great care must be exercised to ensure the sound condition of step ladders and trestles,

particularly of the safety restraints

34.11 WORKING PLACES

Where injury might result, precautions must be taken to prevent falls from any working place.

These precautions will normally consist of edge protection, comprising toeboards at least

150mm high and main guardrails at least 9 -10mm above the working place.

Intermediate guardrails, or other forms of barriers (e.g. brickguards), must also be fitted so

that there is not an unprotected gap of mare than 470mm in height. This standard of edge

protection must, where practicable, always be provided where persons could fall more than

2m.

34.11.1 safety nets and safety harnesses

where it is not practicable to use, bosun’s chairs, cradles etc. as a last resort, safety

harnesses or safety nets may be used. For further information on the use and installation of

safety nets, and on safety harnesses. (see Pt 2 section 12) - PPE, and Pt 2 section 29 -

Scaffolding.



PART TWO



34.11.2 holes in floor

Holes in floors through which a person can fall must be guarded. Alternatively, the hole can

be provided with a cover of adequate strength which must be either marked to indicate its

purpose, or secured in position.

34.12PLANT

34.12.1 power operated platforms

It is important to recognise the limitations as well as the

advantages of such equipment. Normally, they should be

used only to elevate persons. tools and materials into a

position where they can carry out the maintenance work

from the platform.

Persons should not leave the platform whilst in an

elevated position nor should materials be transferred. If

the appliance is used to transfer persons or goods from

one level to another (i.e. not as a working platform), it

may be deemed a hoist or lift and, as such, the relevant

regulations would apply.

Where it is necessary to operate the work platform in

areas congested with live services, the precautions

outlined previously in this section must be adhered to.

(see Fig.1)

Detailed information on power operated platforms is given in (see Pt 2 section 29) –

Scaffolding.

Fig. 1- Power operated platform with a full , and safe working platform and operating controls situated on working platform.



PART TWO



34.12.2 fork lift trucks (also see Pt 2 section 14) – Mobile Plant & Equipment

the provision of a platform on the forks of a fork lift truck is common in maintenance

operations. In such cases the following safeguards are necessary:

• platform to be secured to the forks or

carriage must be provided with double

guardrails and toeboards, and a self-

closing gate (not opening outwards)

interlocked so that it cannot be

opened when the platform is elevated.

Platforms must only be fitted to fork lift

trucks designed for the purpose.

(See Fig. 2)

• on machines with tilting masts, the

mast must be secured in the vertical

position and the horizontal, slip

resistant platform should be as small

as possible, normally large enough to

accommodate not mare than two

persons.

If the truck is fitted with side shift, this should be fixed in mid position.

• the capacity of the machine should be established from the manufacturer and this must

be marked on the truck together with its weight. The platform must not be overloaded.

• additional guarding of dangerous parts of the machine may be necessary.

• only trained competent persons may operate the platform on the fork lift truck.

• preferably, the controls for lifting and lowering should be fitted an the platform.

• fork lift truck must not be travelled whilst a person is an the platform unless the truck has

been specifically designed to allow only small positioning movements at creep speed.

• when a platform is fitted, the fork lift truck should not be used for the transfer of persons

or material from one level to another.

34.13 SCAFFOLDS

The requirements in relation to scaffolds, including slung and suspended scaffolds are

covered in (see Pt 2 section 29). Particular attention must be given to the condition of any

roof or rail used to support cradles.

The use of scaffolds in maintenance work is often hindered by lack of space and by the

difficulty experienced in tying them. These difficulties mainly arise when the building eleva-

tions to be scaffolded do not contain any openings through which to tie, particularly in metal

Fig.2 – Safety Platform specially designed for use with Fork Lift trucks , fitted with a double guardrails and toe boards.



PART TWO



or clad buildings.

This difficulty in tying locations will promote the use of drilled-in anchorage but care must be

taken to ensure that the material into which they are drilled will permit the necessary pull out

values.

Where the structure material is questionable then either of the following tests must be

carried out:-

• proof load of 1.25 times the design load should be applied to at least 1 in 20 anchors.

(minimum 1 anchor)

• test to destruction on at least 1 in 50 anchors (minimum 3 anchors) should be applied

where the strength is judged to be weakest. The lowest Failure value is identified and a

safety factor of 1 .5 applied to determine the safe working load.

If the scaffold is used in places to which the public have access then care must be taken to

remove access ladders at the end of the working day. This is particularly important for the

protection of children.

34.14 DEBRIS FROM WORKING PLACES

• maintenance work often gives rise to the removal of debris and usually this has to be

brought to the ground. Debris must not be thrown from scaffolds etc. but removed in

some contained system. This may take the form of buckets and gin wheels, or similar, or

by the use of chutes.

• chutes should be fully enclosed and have no internal projections which are likely to

retain material discharged into them. The openings at the top of the chutes should be

large enough to adequately to receive the material being put into them. If there is any

risk of spillage then additional protection (possibly mesh) should be fixed around the

opening.

• the discharge end of the chute should also be designed to prevent material bouncing out

of the skip or other receptacle. This is often achieved by wrapping a tarpaulin around the

bottom of the chute and the top of the skip or alternatively by fixing mesh screens to the

side of the skip.



PART TWO



34.15 HEALTH HAZARDS

• persons involved in maintenance work are exposed to many of the same health hazards

that face operatives in the rest of the construction industry. In addition, they may be

exposed to additional health hazards arising out of processes carried out in the building.

• it is essential, particularly when the maintenance is carried out by a contractor with little

or no knowledge of hazards arising out of the processes or plant in the building, that

close liaison exists between the maintenance supervisors, and the persons in control. It

may be necessary that certain medical precautions be taken if the process demands e.g.

work near lead or radiation where initial or periodic medical examinations may be

necessary.

• consideration should be given not only to the processes currently carried out in the

building, but also to those which have been discontinued and may have given rise to

toxic dusts which are still found in pipe ducts etc. Where such a possibility exists, dust

samples should be analysed and all necessary precautions taken.

34.16 TOOLS AND EQUIPMENT

Maintenance work is often considered to be the commercial or industrial equivalent to DIY

but it must be stressed that maintenance work is an industrial activity and the tools and

equipment used should be commensurate with that activity. The standards for tools and

power supplies, etc. are contained in (see Pt 2 section 16) – Portable Tools,

34.17 ROOFS

Work on roofs is the biggest single cause of fatal accidents in maintenance work, either from

falls from the edge or the even greater cause of falls through fragile roof material.

For further information on working on both Flat and Sloping Roofs (see Pt 2 section 32) –

Safe Working on Roofs.

34.18 PROTECTIVE CLOTHING AND EQUIPMENT

• persons involved in maintenance work, particularly when employed by the occupier and

carrying out maintenance work spasmodically may find that there is need for types of

protective clothing and equipment not normally held in the premises.

• the maintenance work may involve the use of eye protection which incorporates Grade 1

impact capabilities, or indeed chemical protection, when all that is held in the Company

stares are general purpose safety glasses.

• ear defenders, generally supplied, may not have sufficient attenuation to protect persons



PART TWO



working adjacent to considerable noise source for long periods, and it would be unlikely

that respirators held in the stores would be suitable to combat specific toxic hazards such

as asbestos or those found when entering confined spaces.

• the person in charge of the maintenance operation must evaluate the hazards associated

with that operation. If the hazards still exist after statutory compliance and carrying out

such measures as are reasonably practicable, but can be further reduced by the use of

protective clothing and equipment, then such clothing and equipment, being suitable for

the operative and for the operation, must be provided, used and maintained.

• in addition, the person using it must be trained in its use and maintenance and given

adequate facility for its storage.

For further information on PPE (see Pt 2 section 12) - PPE.

34.19 MAINTENANCE PERSONNEL

• persons carrying out maintenance work need to be as highly skilled and effectively

supervised as those carrying out other building and construction operations.

• the significant death toll amongst those involved in maintenance work will not be

reduced whilst persons walk directly an fragile roofs, work on platforms and other

working places without guardrails and toeboards or without appropriate safety nets or

harnesses, or work from unsecured ladders, makeshift platforms and fail to observe the

many necessary precautions appertaining to maintenance operations.

• maintenance of premises is not something that should be carried out by unskilled

workers in slack periods, neither should the short duration of many operations cause the

precautions to be ignored. It does not take long for a person to fall to his death.

The use of skilled operatives, who have been trained to recognise hazards associated with

maintenance work and to overcome those hazards, together with adequate supervision and

close liaison with the persons in control of processes carried out in the premises, will go

some considerable way to improve the standards of accident prevention in this hazardous

occupation.

SECTION 35

SECTION 35

SPECIALIST PROCESSES

MAIN APPLICABLE U.A.E. LEGISLATION 1

35.1 HIGH PRESSURE WATER JETTING 2

35.2 LASERS 4

35.3 SITE INVESTIGATION 7

35.4 WATERCRAFT AND DREDGING 11

35.5 DIVING 17



PART TWO


ADM/H&S/Pt 2 01 March 2005 SPECIALIST PROCESSES 1 of 24

SECTION 35


35.1 HIGH PRESSURE WATER JETTING

INTRODUCTION

The term “high pressure water jetting'' covers all jetting including the use of additives and

abrasives at pressure above 140 bars. Pressures currently used can exceed 2500 bar.

This is a high risk operation that requires a high level of supervision and control.

Only adequately trained and competent persons should operate and supervise high

pressure water jetting equipment. The operation is normally carried out by a team and

they should therefore be trained as a team and not as individuals.

Most teams consist of three men:

• supervisor or team leader

• operator at the lance nozzle end of the equipment

• pump operator training must include emphasis on not pointing the lance at parts of the

body even if they are protected by gloves or boots.


Ministerial Order No. (32) Year 1982 - Article (19) B

Ministerial Order No. (32) Year 1982 - Article (1), (6), (9), (15) & (22).




PART TWO



35.1.1 hazards

The main hazards involved in working with high pressure water jetting equipment include:

• use of electricily

• combination of a wet environment and the use of electricity

• pressure injection iniuries

• being struck by material dislodged during operations

35.1.2 precautions

Where possible, the work piece to be jetted should be removed to an isolated area. If this is

impracticable, area limits should be defined with barriers and notices restricting access.

When carrying out the operation with chemical additives, extra precautions may be

necessary, due to the presence of the chemical see Pt 2 section 5 - Substances Hazardous

to Health.

Rigid or semi-rigid lances having nozzles fitted to them with any combination of forward,

backward or 90 degree angle jets shall be used. These must be fitted with a safety shut-off

device or dead mans handle device, which should be checked before use to ensure it is in

good working order.

In certain conditions, e.g. in confined spaces, or in areas surrounded by operational plant,

the operations should be carried out under a permit to work system. Where there is close

interface with normal site operations it may be necessary to carry out work out of hours.

Good access, a safe working platform and secure footing is essential. When working at

heights appropriate fall prevention systems must be in place (see Pt 2 section 29).

Where necessary, safety harnesses should be provided and used.

High pressure water jetting should not be used to clean asbestos cement sheets.

35.1.3 maintenance of equipment

Maintenance schedules, as laid down by manufacturers, should be strictly adhered to.

daily checks should be carried out to ensure that:

• the pump unit lubricant and coolant

levels are up to the mark,

• filters on pump units and suction pick-

up are clear,

• all hoses and connections are in good

condition and correctly made,

• the foot control and guard are

functioning properly,

• all guns/lances, together with jets and

• where the equipment is electrically

operated, all junction boxes, switches

and cables are watertight and free from

defects,

• spark arresters on internal combustion

driven equipment are functioning

correctly,

• a serviceable fire extinguisher, (C02), is

readily available.



PART TWO



orifices, are serviceable and free from

obstruction

All the above should be recorded in a maintenance! inspection, log or register, and any

adjustments to the equipment must not be attempted when it is under pressure.

35.1.4 protective clothing and equipment (see Fig.1)

protective clothing arid equipment should consist of:

• eye protection

• safety footwear including where necessary additional

• strap-on protective shields

• ear defenders

• safety helmets

• waterproof clothing

35.1.5 accidents

Anyone injured while carrying out water jetting

operations can sustain injuries greater than is

possibly visible on the surface.

Medical. advice should be sought immediately

following any injury however minor, and

information should be provided on the nature of the

operation and details of any chemicals involved.

Fig.1 – showing an operator using a portable High pressure Jetting lance to clean concrete, and wearing the appropriate PPE.



PART TWO



SECTION 35


35.2 LASERS

INTRODUCTION

For many years, laser equipment has been finding increasing application in the surveying

and construction industry, offering as it does a means for rapid and accurate alignment and

the facility for precise distance measurement.

As with other civil engineering plant, it is common for firms to hire laser survey equipment

which may then be used by operators who may have received scant training and information

on its safe use. Such equipment will frequently be used on open construction sites with

ready public access.

Most laser instruments have a variety of optical attachments to allow wide changes in the

direction of the beam and its power intensity, which may present significant alterations in the

potential hazard to persons in the vicinity.

It is essential, therefore, that all those involved in the use of lasers, particularly in out-of-

doors situations, where invariably long exposed beam paths are present, are made aware of

the hazards which may exist and the control procedures that are necessary to secure the

safety of everyone, including members of the public.







PART TWO



35.2.1 hazards

Because of the wide ranges possible in wavelength, energy content and pulse length of a

laser beam, the hazards associated with lasers vary widely. It is therefore considered

impracticable to regard lasers as a single group to which common standards can apply.

Three aspects of laser application may influence the total hazard evaluation and thereby

influence the application of control measures:

• the laser or laser system’s capability of injuring personnel, which may include burns to

the skin or severe damage to the eyes,

• the environment in which the laser is used,

• the personnel who operate the laser and the personnel who may be exposed.

Fig.1 denotes the approved type of Safety Signs required when Laser Operations are in

progress.

35.2.2 classification

One practical means of evaluation and control of laser radiation hazards is for the

manufacturer to classify laser products according to their relative hazard potential, following

rules set out in British (and international) Standards and then to specify appropriate controls

for each class. The use of such a classification will, in most cases, preclude on the part of

the end user of the laser product, any requirement for radiometric measurements. BS EN

60825 groups laser products into five classes based on accessible emission levels (AELs),

i.e. the measured level of radiation to which human access is possible. To conform with BS

EN 60825, the manufacturer is required to label the laser product with the classification

number and to provide certain engineering controls, warning signals etc. Corresponding

details on control precautions necessary for the “user” to implement in respect of each class

are also specified in the standard.

Fig.1



PART TWO



35.2.3 precautions

In line with the laser product classification philosophy, the recommendations for laser safety

vary with the class of laser product in use and may be broadly summarised as follows:

Class 1

These products are safe under all viewing conditions but are not practicable for many

construction applications.

Class 2

The laser beam should, where reasonably practicable, be terminated at the end of its useful

path.

The laser should not be aimed at vehicles or personnel, particularly at head height.

Class 3A

While it is preferred that Class 2 laser products be used wherever possible, there are times

when, for example, due to high ambient light levels, more power may be required than is

available from Class 2 laser products. In such cases, 3A laser products may be used but

their use requires additional precautions, e.g.:

• person competent to supervise the safe use of lasers should be appointed wherever

lasers above Class 2 are in use.

• suitable and adequately trained personnel should be assigned to install, adjust and

operate the laser equipment.

• areas where such lasers are used should be treated as controlled areas, be posted with

standard laser warning signs, and access restricted to personnel who have been advised

as to the precautions they should take.

• precautions should be taken to ensure that the laser beam is not intentionally directed at

specularly reflecting surfaces such as mirrors, lenses etc.

• similarly, care must be taken to ensure that such reflecting surfaces are not accidentally

introduced into the beam path.

Class 3B and 4

Such lasers are hazardous, particularly as the beam may be invisible to the eye. They

require extreme caution and careful evaluation prior to their use.

Engineering controls such as physical barriers, interlocks limiting beam traverse and

elevation etc., should be used whenever practicable to augment the administrative controls,

and the need for eye protection must be assessed. (see Pt 2 section 12) - PPE.



PART TWO



SECTION 35


35.3 SITE INVESTIGATION

INTRODUCTION

A site investigation comprises the necessary phases of work entailed in obtaining a

geotechnical and chemical appraisal of a chosen site.

Until the advent of high land prices, investigation was usually confined to natural, or green

field sites. On such sites, if fill material was encountered, it was considered only for its

geotechnical properties. Many investigations are now carried out on contaminated and

derelict sites; such work involves chemists and environmental specialists, to sample and test

for contaminated materials to ensure control or elimination of hazards in the development

and future use of the land.

This section deals only with the safety and health aspects of personnel undertaking site

investigations of land,







PART TWO



35.3.1 phases of site work

A site investigation is made up of the following phases:

desk study

The desk study comprises the inspection of available geological records, Ordnance Survey

data, local archive and authority maps, memoirs and records, aerial photographs and

consultation with public utility authorities.

It is essential to carry out a desk study in order to establish the past usage of a site and thus

to advise contractors of the possible presence of harmful and toxic materials, or

subterranean hazards.

walkover survey

A walkover inspection of a site can provide very useful information with regard to the

planning of the subsequent investigation.

Great care must be taken to avoid falling into unrecorded cavities, such as old mine shafts or

uncapped underground tanks which may have been used as liquor or tar wells at disused

gas works or chemical sites.

The possible instability of staircases and suspended floors must also be considered when

entering derelict structures and basements.

Shafts and manholes must not be entered without taking account of the potential risks from

atmospheric contamination by the ingress of such gases as hydrogen suiphide, methane or

carbon dioxide. Advice on safe systems of work for entry into confined spaces is given in Pt

2 section 21 -Safe Working in Confined Spaces.

trial pits and trenches

which are unsupported should be excavated by machine, or by hand up to a maximum depth

of 1.2m, to enable visual inspection and sampling and simple in situ testing from ground

level. Such pits and trenches deeper than 1.2m must not be entered by personnel.

inspection pits

dug to a maximum depth of 1.2m, for the purpose of locating underground services.

observation pits and trenches,

• excavated by hand or machine, which are properly supported to enable personnel to

enter safely and carry out in situ examination, soil sampling and necessary testing.

• Sampling and testing may need to take place in the side of the excavation, in which case

the support system will need to be designed to allow sections to be exposed, whilst

retaining the stability of the excavation.

Guidance on systems of support is given in Pt 2 section 23- Excavations



PART TWO



• Observation pits or trenches should be checked for gas ingress, or oxygen deficiency,

using a suitable atmosphere testing device, and may need to be treated as confined

spaces, requiring special precautions before entry is permitted. Guidance on appropriate

precautions is given in section 21 - Working in Confined Spaces.

buried services

Prior to any excavation it is essential to obtain all possible relevant information on buried

services from all the appropriate authorities, also from land or building owners.

The position of any services in or near the proposed work should then be pinpointed as

accurately as possible by means of a locating device. Power tools or mechanical excavators

should not be used until the position of services has been confirmed. Further guidance is

given in Pt 2 section 6 – Overhead and Underground Services.

open trenches

• spoil from the pit or trench should not be placed adjacent to the walls of the excavation,

as this causes additional ground stresses and hazards to persons who enter even

shallow trenches.

• in unstable ground, a continuous check must be made for the presence of tension cracks,

which may indicate the imminent collapse of a trial pit or trench.

35.3.2 boreholes

The general safety and health precautions to be adopted by personnel operating and

supervising the construction of boreholes are similar to those discussed in the paragraphs

dealing with the excavation of trial pits. In addition, attention must be given to the stability

and operation of the drilling rig, deep services and tunnels, overhead power cables and

noise.

It is essential that the boring or drilling rig is set up in a stable manner. This is of particular

importance when working on sloping ground.

The precautions already outlined for avoiding underground services apply equally to bore

holes. However, due to the greater depth of penetration, consideration must be given to the

possible presence of deep sewers, gas mains and cable tunnels.

The noise from drilling and boring rigs should be assessed and, where possible, reduced.

Where persons are likely to be exposed to 90 dBA, or above, over a working day, hearing

protection must be provided and worn.

Further guidance on noise is given in Pt 2 section 3 – Noise at Work.

Persons must not enter a borehole of less than 760mm diameter. Suitable equipment must

be used for lowering a person into the hole and a Type E safety harness must be worn. A

rescue procedure must be prepared and persons trained in its operation.

Further guidance is given in Pt 2 section 21 – Safe Working in Confined Spaces.



PART TWO



35.3.3 in-situ loading tests

Large scale loading tests, normally up to a total load of 1,000 tonnes, are carried out on test

plates positioned in trial pits or boreholes, or on test piles, to check the validity of design.

Where tests require the use of grillages to support dead weight kentledge or anchored

reaction cables, it is essential to establish that the ground below the grillage is able to safely

support the imposed loading. Care must be taken not to work or walk in the line of anchored

cables.

All test equipment must be checked and calibrated before use to ensure that the correct

pressure or loading is applied to the test plate or pile.

The lifting appliance and lifting gear used to place load test materials must be suitable for the

purpose and have current test and examination certificates. The ground bearing capacity of

the surrounding area must also be considered before putting a lifting appliance to work.

Further guidance on lifting appliances and lifting gear is given in Pt 2 section 19 - Cranes

and Hoists and section 20- Lifting Gear.

35.3.4 occupational health and first aid

Because of the sometimes isolated nature of sites and the possibility of dealing with

contaminated land, the following basic health and first aid measures should be considered:

protective clothing

Suitable protective overalls, gloves, safety helmets, and protective footwear must be

provided. All items should be selected to provide the degree of personal protection that

ensures adequate protection for the worst case of contamination. Hand protection is

essential when handling samples.

washing facilities

The provision of washing facilities is essential for use prior to eating, smoking or attending to

bodily functions.

bacterial infection

Persons engaged in handling samples should be encouraged to keep up to date with anti

tetanus injections and be provided with information regarding Ieptospirosis (Weil’s Disease),

first aid

First aid provisions should be made depending on the size of workforce but, as a minimum,

there should be a travel pack with each vehicle

emergency procedures

Instructions must be available to deal with emergency situations involving accidents to

persons or plant, fires, flooding, explosions and, in particular; the striking of overhead or

underground services etc.



PART TWO



35.3.5 site security

Where site investigation operations extend over a period of days or weeks, particularly if the

work is carried out on contaminated land, measures must be adopted to ensure, as far as

possible, that trespassers, vandals or children are denied access to the site.

Fencing of site operations, securely covering excavations, isolating all plant and equipment

and ensuring secure storage of materials are essential minimum procedures to be adopted.

If the excavated spoil is contaminated, the hazard should be clearly indicated on notices.



PART TWO



SECTION 35


35.4 WATERCRAFT AND DREDGING

INTRODUCTION

This section sets out the requirements for watercraft and dredging. The requirement for

actual watercraft and dredging equipment is also discussed, as well as the requirements for

personnel performing such watercraft and dredging operations.

Inspection, training, certification and various operating activities are discussed in detail.




inisterial Order No. (32) Year 1982 – Article (20)



PART TWO



35.4.1 general requirements for watercraft operations

construction of vessels

To construct all watercraft and perform all watercraft operation in accordance with the

standards and local requirements laid down by the Abu Dhabi Coast Guard and Marine

Department.

inspection and certification

Inspect, certify, license, and number all watercraft and equipment according to standards

and local requirements laid down by the Abu Dhabi Coast Guard and Marine Department.

capacity plates

Plainly marked on all watercraft with the maximum occupancy and carrying capacity allowed

on board for safe passage. Do not exceed this maximum occupancy or carrying capacity.

loading

make sure that each boat has enough room, freeboard, and stability to safely carry the

maximum cargo and passenger under various weather and water conditions.

flame arrestors

Equip gasoline engines, except for outboards types, with an approved backfire flame

arrestor. Make sure the arrestor is attached to the air intake with a flame – tight connection.

It must be kept clean and in serviceable condition.

fire extinguishers

For watercraft less than 65 feet in length, a minimum two x 10lb Dry Powder extinguishers

should be provided. Watercraft 65 feet or larger must carry sufficient fire extinguishers to

meet Abu Dhabi Coast Guard and Marine Department’s requirements.

ventilation

Watercraft with permanently installed gasoline engines must have powered ventilation

systems to remove gasoline vapours from the vessel.

fuel

Fuel must be stored in approved containers suitable for marine use. Fuel lines must be

equipped with a valve to cut off fuel flow. In addition, if the watercraft will not be in use for a

period of 8 hrs or longer, then the valve must be closed.

navigation lights

Watercraft must be able to display navigation lights required by the Abu Dhabi Coast Guard

and Marine Department. Display navigation lights between sunset and sunrise and any other

time visibility is reduced (fog, haze, rain etc).



PART TWO



operator training and qualification

Reclamation employees and others who operate a Reclamation – owned watercraft must

first be certified or licensed to operate the watercraft in accordance with the Abu Dhabi

Coast Guard and Marine Department.

float plans

If the operator expects watercraft to activities to take longer than 4 hrs from time of departure

until time of return, a float plan must be prepared. The float plan must include the following

information:

• watercraft information (vessel, make, model or local identity).

• personnel on board

• activity to be performed

• expected time of departure, route and time of return.

• means of communication.

personnel floatation devices (PFD)

Equip watercraft with one approved PFD for each occupant, and one approved throw line

type onboard the watercraft. Wear a PFD whenever you are onboard or working around

bodies of water where drowning hazard exist. For further information on PFD see Pt 2

section 28 - Working over or adjacent to Water.

safety equipment

Equip all watercraft with adequate safety equipment to meet the Abu Dhabi Coast Guard and

Marine Department’s requirements and any hazards that may be encountered during normal

operations.

swimming

No one should swim from the watercraft or any floating equipment unless you are a certified

diver whose duties require such swimming.

35.4.2 dredging operations

inspections

A qualified person must inspect dredges and related equipment before they are entered into

service, and at least yearly thereafter to make sure they are in a safe operating condition.

The inspector must have a recognised degree, certificate or licence, or professional

standing, as well as extensive knowledge, training and experience in solving problems

related to the work. Inspections must be documented and accessible to personnel.



PART TWO



maintenance and repair

Before performing repair or maintenance work on the pump, suction or discharge lines below

the water line, or within the hull, in addition to the normal process of securing hoisting

machinery, you must raise the ladder (or drag arm) above the water line and positively

secure it. Set blank or block plates in suction or discharge lines as appropriate.

pipeline marking

Dredge pipelines that float or are supported on trestles must display lights at night and when

visibility is restricted.

safety plans

Prepare a comprehensive safety plan for each dredging operation that may pose hazards to

navigation or to the public.

submerged dredge pipeline

• where a pipeline crosses a navigation channel or other area subject to boat traffic,

submerged pipeline must rest on the channel bottom. The top pipeline and any anchor

securing the pipe must be no higher than the maximum draft of traffic expected in the

area where pipe is placed.

• when buoyant or semi buoyant pipeline is used, the dredge operator must make sure the

pipeline remains fully submerged and on the bottom. When raising the pipeline, warn

boat traffic of the pipeline hazard. Adequately mark the entire length of the pipeline.

• mark the entire location of the submerged pipe to ensure anchorage.

• remove all anchors and related materials when removing the submerged pipe.

floating pipeline

Floating pipeline is any pipeline not anchored on the channel bottom. Clearly mark floating

pipeline, including rubber discharge hoses. Do not allow pipelines to fluctuate between the

water surface and the channel bottom or to lie partially submerged.

If floating pipelines are used as accessways, equip them with a walkway and handrail on

one side. Personnel using the walkway must wear an approved (PFD)

dredge design

Design dredges so that failure or rupture of any of the dredge pump components (including

dredge pipe) will not cause dredge to sink.

dredge pumps

Any dredge with a dredge pump below the water line must have a bilge alarm or

automatically shutdown in the event of a pump leak.



PART TWO



fall protection

Provide guard rails, bulwarks, or taut cable guard lines for deck openings, elevated surfaces,

or other locations where a person may slip or fall from them.

walking and working surfaces

• provide anti slip surfaces on all working decks, stair treads, vessel ladders, and other

walking or working surfaces that may become wet during operation.

• remove obstructions in walking and working surfaces if possible. Where obstructions

cannot be removed, post appropriate warning signs or distinctively mark them.

• where the distance between the vessel and docks or landing exceeds 18 inches

horizontal, or 12 inches vertical, provide gangways. Gangways must be at least 22 inches

wide, with standard railings and able to support 250 pounds (with a safety factor of 4-1) at

its midpoint.



PART TWO



SECTION 35

SPECIALIST PROCESSES 35.5 DIVING

INTRODUCTION

In the absence of any specific U.A.E. Safety Regulations covering Diving Operations, ADM

have decided to use, as their standard, the current United Kingdom’s Diving At Work

Regulations 1997 as a guideline, and have based the following procedure on the above

Regulations and expect, as far as is reasonably practicable, all diving operation carried out

on any of their Projects to meet the following standards.


None present - refer to Ministry of Labour & Social Affairs

MAIN APPLICABLE INTERNATIONAL LEGISLATION

The Diving at Work Regulations (DWR) 1997



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35.5.1 application of the standards

These standards are concerned with the safety of divers working as employees or in a self-

employed capacity. They are also concerned with the safety of any person who is exposed

to a pressure greater than 300 millibars above atmospheric pressure, either in a surface

compression chamber used in connection with any diving operation, or in the testing or

evaluation of any plant or equipment for use in diving operations.

The standards apply to diving operations from the time a diver commences his preparations

for diving until he has left the water, and is no longer subject to raised pressure and it may

reasonably be anticipated that he will not need therapeutic recompression.

Diving supervisors, all members of the diving team, and any person concerned with the

recompression or decompression of a diver are deemed to be engaged in a diving operation.

35.5.2 exemptions from the application of the standard

These standards do not apply to diving operations in which the diver uses a submersible

craft or a pressure resistant suit, and whilst doing so is exposed to a pressure no greater

than 300 millibars above atmospheric pressure. Neither do the regulations apply where the

diver uses no underwater breathing apparatus or only snorkel type apparatus.

35.5.3 people involved in the diving project

the client and others

There are a number of people whose actions can affect the safety of the diving project, even

though they are not part of the diving team. These people include the client for whom the

diving project is being carried out. Others include vessel operators and the owners of the site

where the diving project is taking place.

Although their responsibilities vary, they all have a duty to co-operate with the diving

contractor and supervisor. This is to ensure that standards are complied with, and that their

actions do not affect the safety of the dive team.

The client who commissions the work has responsibilities which include:

• ensuring that they appoint a diving contractor who is competent to undertake the duties;

• ensuring that the site is safe to use;

• identifying known hazards to the diving contractor, such as underwater obstructions and

contaminated water;

• supporting the supervisor and diving contractor in the event of an emergency.



PART TWO



the diving contractor

The diving contractor is normally the person who employs the divers for a diving project. A

diving project is the term used for the overall diving job (whether it lasts two hours or two

months). Depending on the size of the diving project, it can be made up of a number of

diving operations. A diving operation is the portion of the diving project which can be safely

supervised by one person. A supervisor must be appointed for each diving operation.

The diving contractor is the person who plans and conducts a diving project. No diving work

may go ahead without a diving contractor being appointed.

The diving contractor has the main responsibility to ensure a safe diving project. The diving

contractor should ensure that the diving project is planned, conducted and managed in a

safe way.

The diving contractor's responsibilities include:

• assessing risks, and ensuring that a diving project plan is prepared;

• ensuring that the dive team is aware of the plan;

• ensuring that there are suitable and sufficient divers who are competent in both diving

and the actual work to be undertaken, such as in the use of tools;

• ensuring that the place from which the diving is to be carried out is suitable and safe;

• providing sufficient and suitable plant and equipment, and ensuring that it is correctly

certified and maintained;

• ensuring that adequate arrangements exist for first aid and medical treatment;

• ensuring that diving project records are kept;

• ensuring that all other relevant regulations are complied with.

the supervisor

The supervisor must be appointed in writing by the diving contractor.

The supervisor should be qualified as a diver, and be competent in the techniques being

used in the diving project.

Supervisors are responsible for the safety of the diving operation that they are supervising,

and should be on site and in direct control of the diving operation.

The supervisor's responsibilities include:

• checking that divers are competent to dive and can carry out the work underwater;

• ensuring that everyone in the diving operation is aware of the diving project plan, and

that the plan is kept up to date;

• maintaining proper records of the diving operation;

• ensuring that there is adequate communication with the divers in the water;



PART TWO



• checking the site on the day of the dive, and when conditions change, confirming that

the risk assessment is still current;

• checking that the diving equipment provided is appropriate and adequate for the project.

the divers

Divers have a number of responsibilities. These include:

• holding an approved qualification for diving;

• being competent to work safely;

• holding a valid certificate of medical fitness to dive;

• complying with the directions of the supervisor and the dive plan;

• maintaining a daily record of their dives which they should keep for at least two years.

35.5.4 diver competence

All divers at work must be competent and hold an approved qualification.

There are three standards of competence. These are the main techniques used for

commercial diving:

• Surface Supplied

• SCUBA

• Closed Bell

If divers hold an Surface Supplied for onshore surface supplied diving, and want to work

offshore using surface supply, they will need to be assessed against a 'top up' standard.

Only divers with a Surface Supplied Top Up are eligible to be assessed for a Closed Bell

certificate. Before assessment, they must have gained at least one year's diving experience

at that level.

If a person fails to reach the required competence, a diver assessment organisation will

refuse to award the qualification.

35.5.5 medicals

Divers must hold a certificate of medical fitness to dive issued by an approved medical

examiner of divers.



PART TWO



The medical examiner considers the diver's ability to meet the physical requirements of

diving work and the physiological consequences of work under pressure. If passed fit, they

are given a certificate of medical fitness to dive, which they must show to prospective

employers.

It is the responsibility of both the diving contractor and the supervisor to ensure that divers

are medically fit and hold the relevant certificates.

Divers must see an approved medical examiner at intervals, not exceeding 12 months, for

an assessment of their fitness to work underwater for the next 12 months. They may decide

to take the medical up to one month before the expiry date. This certificate is valid for 12

months from the original expiry date, and not from the date the medical was taken.

The cost of the medical varies, depending on any further tests that a medical examiner may

have to carry out.

35.5.6 first aid

The diving contractor has a responsibility to ensure that suitable and sufficient people are

available at the dive site to provide first aid.

As part of diver training and assessment, divers are taught diving physiology (which includes

the function of the nervous and musculoskeletal systems), and diving medicine (which

includes decompression illness and ear problems).

First Aid training should provide the immediate initial treatment to reduce the effects of the

common injuries or illnesses suffered at work, for example bleeding, fractures, shock, burns

and respiratory arrest.

When considering who should be in a dive team, the diving contractor will include people

who can offer these skills.

As divers may forget their first-aid skills over time (hopefully they will not need to use them),

they may decide that carrying out refresher first-aid training will improve their employment

opportunities.

his must be done with a recognised first-aid organisation.

Refresher training should be done before the diver's current certificate expires. If undertaken

up to three months before the expiry date, the new certificate will be valid from the original

expiry date and not the date the refresher course was completed.

It may also be necessary to train divers in other first-aid procedures such as the emergency

administration of pure oxygen to an injured diver.



PART TWO



35.5.7 client / main contractor basic checklist

• has the diving contractor been appointed in writing?

• is the diving company a registered diving contractor?

• have the diving supervisors been appointed in writing?

• is there a Diving Operations Log Book? (see chapter below)

• do all divers have valid certificates of training for the type of diving to be executed?

• are all diving personnel in possession of an in date Diver First Aid Certificate?

• where required, do suitable persons have Diver-Medic Certificates?

• do all divers have valid Certificates of Medical Fitness?

• are there sufficient divers to safely execute all planned work?

• are there Diving Rules on site for the work being executed?

• does each diver have a copy of the relevant parts of the Rules?

• is all the correct plant and equipment on site?

• are there valid Certificates on site for this plant and equipment? Are they attached or

contained in a register kept for the purpose?

• is the correct first aid and medical equipment, medication, etc. available?

• has a method statement been produced detailing the diving work to be executed, means

of notifying other persons (including Port Authorities) that diving is being undertaken and

for raising the alarm in the event of an emergency.

35.5.8 matters to be entered in the diver’s logbook

The following matters shall be entered in the diver’s logbook in respect of each diving

operation in which he takes part:

• the name and address of the diving contractor

• the date

• the name or other designation and the location of the offshore installation, work site, craft

or harbour from which the diving operation was carried on

• the name of the diving supervisor

• the maximum depth reached on each occasion



PART TWO



• the time he left the surface, his bottom time and the time he reached the surface on each

occasion

• where the dive includes time spent in a compression chamber, details of any time spent

outside the chamber at a different pressure

• the type of breathing apparatus and mixture used by him

• any work done by him on each occasion and the equipment (including tools) used by him

in that work

• any decompression schedules followed by him on each occasion

• any decompression sickness or other illness, discomfort of injury suffered by him.

35.5.9 consideration in respect to diving operation plans

planning

Consideration of:

• meteorological conditions, including forecasted conditions

• tidal information including local tide tables and indications of speed of current to be

expected

• proposed shipped movements

• underwater hazards of the diving site, including any culverts, penstocks, sluice valves or

areas where differences in hydrostatic pressure may endanger the diver

• depth and type of operation

• suitability of plant and equipment

• availability and qualifications of the person and the effect on a diver of changes of air

pressure if he flies after diving

• the activities of any person who will be diving in connection with the diving operation

whether or not he is a diver for the purposes of these regulations.

preparations

Consultation with persons having any control over or information related to the safety of any

diving operation; and in particular persons having control of lifting appliances or having

control of information about shipping movements.

• selection of the breathing apparatus and mixtures

• check of plant and equipment

• allocation of personnel



PART TWO



• personal fitness of divers for underwater operations

• precautions against cold in and out of the water; signaling procedures

• precautions against underwater hazards of the diving site

procedures during diving

Responsibilities of diving supervisor, divers and surface support:

• use of all types of personal diving equipment

• supply of gas and gas mixture, including

• maximum and minimum partial pressure of gases

• operations direct from an installation, work site or craft

• operations in relation to diving bell

• working in different locations

• operations and use of equipment under water

• limits on depth and time under water

• descent, ascent and recovery of divers

• descent, ascent and recovery of diving bell

• diving tables for use in decompression procedures for both single and repetitive diving

and in therapeutic decompression procedures; and for inland waters the need to take

account of the effect on pressure of the altitudes at which the diving takes place

• control in changing conditions

• time for which divers are to remain in vicinity of the surface compression chamber

• maintenance of logbooks.

emergency procedures

• emergency signaling

• emergency assistance under water and on the surface

• therapeutic recompression and decompression and the availability of chambers for that

purpose

• first aid and medical assistance (see note below)

• calling assistance from emergency services including advance liaison with those services

where appropriate

• precautions in the event of evacuation of the installation, work site, vessel, hovercraft or

floating structure

• provision of emergency electrical supplies



PART TWO



part 2 - english

Documents

safety standards

adm health

health risks

safety requirements

safety of persons

safety unit

health overhead

hs adm consultant health