high pressure water jetting

Procedure

OS.SICES.High Pressure Water Jetting Version No 1.0 of 28

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Copyright and intellectual property rights embodied in this document remain vested in Contract Resources Pty Ltd (ABN 63113182504). Except as provided by the Copyright Act 1968, no part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means without the prior written permission of Contract Resources Pty Ltd.

High Pressure Water

Jetting Mar 2009

Contract Resources Group OS.SICES.High Pressure Water Jetting

Version No 1.0 Date Last Modified 22/11/2010 3:44 PM Author Mike Fitzpatrick Pages 2 of 28

Contents

1 SCOPE .............................................................................................................................4

2 OBJECTIVE .....................................................................................................................4

3 DEFINITIONS ...................................................................................................................4

4 RISK CONTROL APPROACH TO HYDRO JETTING ......................................................6

5 PERSONNEL TRAINING REQUIREMENTS ....................................................................7

5.1 BASIC INTRODUCTION LEVEL.................................................................................................... 7

5.2 INTERMEDIATE LEVEL .............................................................................................................. 8

5.3 SUPERVISOR/ ASSESSOR LEVEL .............................................................................................. 8

6 PERSONAL PROTECTIVE EQUIPMENT ........................................................................8

7 GENERAL CONSIDERATIONS .......................................................................................9

7.1 HOUSEKEEPING .................................................................................................................... 12

7.2 WORKING SURFACES ............................................................................................................ 12

8 EQUIPMENT AREA PREPARATION .............................................................................12

8.1 GENERAL PREPARATIONS...................................................................................................... 12

8.2 WORK LOCATION PREPARATIONS ........................................................................................... 13

8.3 WATER SUPPLY ................................................................................................................... 13

8.4 PERMIT REQUIREMENTS ........................................................................................................ 13

8.5 ENVIRONMENTAL CONSIDERATIONS ........................................................................................ 13

9 TOOL AND MACHINE REQUIREMENTS ......................................................................13

10 WORK PRACTICES .......................................................................................................14

11 MANUAL TUBE FLEXI-LANCING .................................................................................15

11.1 USE OF MINI MOLES (BOILER SNAKES) .................................................................................. 15

11.2 GENERAL REQUIREMENTS ..................................................................................................... 16

11.3 DO’S AND DON’TS OF MANUAL TUBE FLEX LANCING ................................................................ 17

12 HPWJ GUN JETTING ....................................................................................................18

12.1 GENERAL REQUIREMENTS ..................................................................................................... 18

12.2 DO’S AND DON’TS OF SAFE GUN JETTING ............................................................................... 19

13 RIGID LANCING ............................................................................................................20

13.1 DO’S AND DON’TS OF RIGID LANCING..................................................................................... 21

14 APPENDIX 1 CHECKLIST TO START AND OPERATE HPWJ .....................................22

15 RESPONSIBILITIES .......................................................................................................23

16 ASSOCIATED DOCUMENTS.........................................................................................23

17 REFERENCES ...............................................................................................................23

18 ENVIRONMENTAL IMPACTS AND ASPECTS STATEMENT .......................................23



COMPETENCY ASSESSMENT .............................................................................................24

AUDIT.....................................................................................................................................26

AUDIT.....................................................................................................................................27

AUDIT.....................................................................................................................................28



1 Scope

This procedure has been developed to address the features of high pressure water

jetting (HPWJ) equipment and define the minimum requirements for its safe operations

and use.

2 Objective

This procedure has been developed to address the inherent risks of hydrojetting and to

provide minimum requirements for the safe operations of hydrojetting or water jet

cleaning equipment.

All high pressure water jetting equipment and actions will comply with – Australian/New

Zealand Standard AS/NZS 4233.1 “High Pressure Water (Hydro) Jetting Systems;

Part 1: Guidelines for Safe Operation and Maintenance

Part 2: Construction and Performance.

Equipment that does not comply with AS/NZS 4233 will not be used.

3 Definitions

Anti-Withdrawal - A device-prevents a nozzle from reversing direction inside a pipe

and re-exiting

Automatic Unloader - A device (valve) which automatically removes operating

pressure on the pump by opening a free flow path for the pump output when it senses

the line to the nozzle is closed. It automatically adjusts the amount of water sent to the

nozzle line, dependent on the pressure set by the operator and the capacity of the

pump.

Burst Disc - A safety device designed to rupture and discharge the fluid so as to

prevent a safe pre-determined pressure being exceeded. (Once “burst” needs to be

replaced before operations continue)

Class A Systems - High pressure water jetting systems are identified as Class A

systems when the maximum energy produced by the system, measure in pressure

volume units per minute (e.g. bar litres/minute), falls in the range 800 bar litres minute

and 5600 bar litres/minute

Class B Systems - High pressure water jetting systems are identified as Class B

systems when the maximum energy produced by the system, measure in pressure

volume units per minute (e.g. bar litres/minute), exceeds 5600 bar litres/minute

Dry Shut-Off Valve - An operator's control valve which has the capability to completely

shut off flow to the nozzle. Typically seen as a hand gun or a foot valve. Should only

be used in conjunction with a regulator or automatic unloader valve

Dump System - An operator controlled system that opens a free flow path for the

water, thereby reducing the system pressure to a safe level without shutting off the f low

to the nozzle



Flex Lancing - A flexible tube used to feed a nozzle through an enclosed space such

as a pipeline. The flexible lance is most commonly used where a tube contains one or

more bends

High Pressure Water Cleaning (HPWJ) - The use of high pressure water, with or

without the addition of other chemicals or abrasives to remove matter from various

surfaces

High Pressure Water Jetting System - A water delivery system consisting of an

energy source, pump, control mechanism, hoses, pipes and nozzles and other

attachments necessary for the equipment to function as a system

High Pressure Hose - Flexible hose used to transfer high pressure water from the

pump to the cleaning tool being used

Hose Restrainer - Hose restrainer, constructed either of nylon or braided wire that

spans a hose connection. It prevents the hose from separating in an uncontrolled

manner should the connection between the hoses fail

Jetting Gun - A portable combination of operators control valve, lance and nozzle,

resembling a gun in layout and outline

Lancing - A lance and nozzle combination is inserted into, and retracted from, the

interior of a pipe or tube. It may be self propelled by its backward directed jets and

may be manufactured in various shapes, sizes and combinations of rotating forward

and backward directed jets. Lancing is most commonly used for cleaning heat

exchanger tubes

Moleing - A hose fitted either with a nozzle or a nozzle is attached to a lance is

inserted into, and retracted from the interior of a pipe. It is a system used to blast

deposits out of the end of a pipe or commonly intended for cleaning the internal tube.

Moeling is generally used with larger piprs

Nozzle - A device with one or more openings orifices where the fluid discharges from

the system. The nozzle restricts the area of flow of the fluid, accelerating the water to

the required velocity and shaping it to the required flow pattern and distribution for a

particular application. Combinations of forward and backward nozzles are often used

to balance the thrust. Such nozzles are commonly referred to as tips, jets or orifices

Regulator Valve - Automatically adjusts the amount of water sent to the nozzle line

dependent on the pressure set by the operator and the capacity of the pump

Rigid Lance - A rigid tube with a nozzle attachment that can be either hydraulically or

manually driven through straight tubes. Rigid lancing is an alternative to flexible lance

cleaning of tubes

Restraining Clamp - A clamp used in the anti-withdrawal device

Rota Fan - A trolley-mounted low-speed rotary joint that rotates a non-rotating nozzle,

via the hose

Safety Valve - A valve which automatically, without the assistance of any energy other

than the fluid consumed, discharges a certified quantity of the fluid so as to prevent a

predetermined safe pressure from being exceeded

Safety Observer - Is a member of the work crew assigned the following tasks:



o Observing the jetting operations and barricaded area;

o Shutting down the system in the event of an emergency or malfunction

o Controlling the system pressure as requested by the jet operator

o Controlling the access of personnel into the barricaded area

Securing Device - Immobilizes the work piece by securing it to the ground or a non-

movable base

Shot Gunning - An activity where a jetting gun is used to blast deposits out of the end of

a pipe or tube. The gun is commonly fitted with a shrouded nozzle which is pushed

firmly against the opening of the pipe or tube while the jet is operated in short bursts

Starter Bar - A rigid piece of pipe affixed to a line mole to prevent reversing of mole in

the line

4 Risk Control Approach To Hydro Jetting

It is recognised by Contract Resources that HPWJ is an activity with significant inherent

hazards that if approached inappropriately, presents significant risk with the potential

for serious injury, including fatality.

As such, Contract Resources when undertaking risk assessments during planning and

operational services will ensure risk is maintained to as low as reasonably practicable

by adopting the principles and practices detailed in our Risk Management Procedure.

Reference: HSEQ.PRO.Risk Management

Key considerations for risk management:

Where possible HPWJ will be avoided. Other methods of cleaning will be

proposed to the client and if approved implemented (e.g. chemical cleaning)

Where HPWJ is required, Contract Resources will use various remote controlled

mechanical devices in order to separate the operator from the high pressure

water hazards. For example:

Task Equipment

External bundle cleaning Automated external bundle cleaner

Internal bundle cleaning

Use automated internal tube cleaner

which may be rotating dual rigid

lance or a free lance machine

Internal shell cleaning Use of centralizer

Cleaning of large surfaces Use of excavator with high pressure

water head

Cleaning/finishing of tank floors Use of HPW “lawnmower”

Contract Resources operators shall be instructed trained and competency assessed

prior to the use of these machines and devices.



On every job, a competent, trained and experienced person must be present

A lance or gun can be operated by a person trained to the introductory HPW

standard as long as all HPW guidelines including back out prevention are

followed

The manual use of HPWJ equipment will only be utilized as a last resort where

the use of other automated or mechanical equipment cannot be employed

When manual flexi lance cleaning of exchanger tubes is required, fail safe (anti-

withdrawal) devices attached to the equipment must be used to prevent the lance

exiting the tube in an uncontrolled manner

Where manual flexi lancing using mini moles (boiler snake) is to be employed by

Contract Resources personnel, a JSEA must be prepared and approved by the

Contract Resources General Manager or their delegate prior to commencement

of the job

Prior to use of equipment Contract Resources personnel must have been trained

and demonstrated competency in the Contract Resources Standard Operating

Instruction specific to the equipment used

5 Personnel Training Requirements

Within Contract Resources we identify 3 levels of HPWJ operators:

5.1 Basic Introduction Level

Individual is new to the industry and has no or very minimal experience with HPWJ.

This operator will be involved in high pressure water jetting jobs under supervision of

an experienced operator.

All people involved in HPWJ operations must be at least 18 years of age, Contract

Resources and site inducted and must have successfully completed the IFAP

Introduction to Hydroblasting Certificate course unless:

They are involved in a training exercise

They are only involved in operating a safety stop/device and signed off as

competent against an SOI

Contract Resources HSET Coordinators have signed off on any prior/non IFAP

accredited course until one can be completed

Following training, Supervisors or nominated Advanced HPWJ trained people are

able to deem someone competent against an SOI.



5.2 Intermediate Level

The Operator needs to have successfully completed the IFAP intermediate high

pressure water blasting course.

Operators at this level are able to plan, execute and oversee a safe hydro jetting

project to a pre determined quality outcome.

5.3 Supervisor/ Assessor Level

Individuals at this level have extensive experience in supervising and/or assessing

and through recognition of prior learning, may not be required to participate in a

HPWJ training course.

This operator is in charge of the job site and is responsible for the set up and

barricading of the area and safe execution of the job. They are also responsible for

the training/coaching of lower level operators and client liaison.

Operators in this level will have completed an accredited OH&S course.

5.4 General

Each person directly engaged in HPWJ will be required to have satisfactorily completed

an approved HPWJ training course. In addition, personnel may also be required to be

trained and certified as safe to operate associated HPWJ equipment, such as

excavators and the necessary personal protective equipment use.

The Contract Resources Supervisor responsible for the job must verify proof of

training.

Records will be maintained on the Contract Resources training register

HPWJ personnel will be familiar with the requirements of these safety guidelines.

6 Personal Protective Equipment

Whenever HPWJ is to be performed, a JSEA of the job must be completed and

appropriate PPE must be used for job hazards identified.

The risk assessment will determine if any additional or specialised personal protective

equipment is necessary. Any additional precautions concerning protective equipment

must be stated on the work permit.

Persons not involved in the cleaning are to be excluded from the work

area. The work area will be clearly marked with warning tape and signs

warning that HPWJ activities are in progress.

The operator and those within the HPWJ area are required to wear as a minimum the

following protective equipment when cleaning:

Hardhat

Safety glasses/goggles and



Face shield

Hearing protection (minimum of 27bba attenuation, however consideration should

be given to wearing dual hearing protection – ear plugs and ear muffs)

Heavy duty rain suit or HPWJ suit

Protective gloves (dependant on the material/substance being handles or

exposed and the hazard and risk presented to the operators)

HPWJ safety rubber boots (with built in metatarsal protection) with steel caps or

approved HPWJ boot over-protectors

Other equipment as required if a hazardous chemical is involved

Other PPE can be considered depending on the project and risks identified

7 General Considerations

HPWJ or water jet cleaning equipment has varying working pressures and flow rates.

The operating pressure should never exceed the rated pressure of the equipment.

WARNING: When HPW Jetting using hand held equipment, a combination

of pressure and flow rate can produce significant recoil force and torque

that may create an uncontrollable situation. This must be considered

when documenting the JSEA and appropriate controls implemented to

manage the risk to as low as reasonably practicable

Prior to commencing any HPWJ work the operators must ensure that the

following occurs:

o A JSEA must be prepared and authorised by the operators

performing the work and the client representative

o The Checklist to Start and Operate High Pressure Water Equipment

(appendix 1) must be completed

o The equipment log book must be completed

The cleaning equipment should be set-up whenever possible to have minimal

impact on the surrounding site activities, out of major personnel traffic routes, and

where possible a safe distance from operating equipment as determined by the

operating pressure and flow rate of the HPWJ equipment

Note: If possible, the HPWJ equipment and work should be located off-site and

equipment to be cleaned (e.g. exchanger bundles) transported to the remote

cleaning site



If access to a cleaning area is required, the individual requiring access to the

work area must obtain permission from the work Supervisor prior to entry to the

area

Where an unauthorized person enters the cleaning area, the work Supervisor

and/or the HPWJ operator must stop operations. Work must not resume until the

area is cleared

Special HPWJ requirements that deviate from these guidelines must be covered

by a JSEA developed by Contract Resources in conjunction with the client to

ensure that a suitable work procedure is adopted and all safety precautions are

identified. The risk control hierarchy method must be followed

Schedule the work so the number of authorized plant and other contractor

personnel in the area is held to a minimum

For environmental purposes, HPWJ activities should where possible be

scheduled and located such that the impact of noise associated with these

activities has minimal impact on the surrounding community and site work force

The HPWJ equipment area must be barricaded using recognised barricade tape.

The “exclusion zone” surrounding the operator of the high pressure jetting

equipment defined by the barricade tape and warning signs must be such that a

passer-by cannot come into contact with high pressure water or debris. Where

barricading tape is difficult to erect (e.g. lay down areas, etc) the use of additional

signage or other means of restricting access/barricading and notifying personnel

of a work hazard must be considered

It may be required that the barricading and warning signs are placed at a

distance greater than five (5) metres from the work zone where there is the risk

that personnel may be struck by high pressure water or debris removed during

the cleaning process

The Barricade tape and signs should surround hoses extending from pump

equipment to cleaning area where there is risk of damage to the hoses or they

present a safety risk to other site personnel. There is no restriction on the

number of signs to be erected, but as good safety practice, at least two warning

signs, stating “Danger, Water Blasting in Progress” must be erected around the

work area

In the event it is not possible to control access to the work area or ejection of

debris or water from the work area, sturdy barriers/panels must be placed/erected

to shield operations



The pumping unit must be equipped with a safety valve and/or rupture disc

capable of rapidly relieving the full capacity of the pump. The burst pressure

rating of the rupture disc must comply with the requirements of AS/NZS 4233.1

(1999). The disc and or safety valve will be checked as part of the annual

maintenance program on this equipment

The pumping unit should be located to minimise the length of hoses required.

Considerations should be given to the distance from operating equipment. Select

a location that does not require running hoses through an active access way or

work area. Care must be taken to protect hoses from damage by vehicle traffic,

hot lines/equipment, or external abrasion

The operating pressure of the high pressure hose and fittings must comply with

AS/NZS 4233.1. Hoses should be inspected before each job and tested

according to the requirements of that standard. Hoses must be identified in such

a manner that the latest test date and test pressure can be determined

Hydro blasting equipment must be earthed/bonded to minimize static electricity

build-up

Hose connections must have a secondary joining mechanism (e.g. hose restraint

device) to prevent whipping if the connection is broken

Although no minimum length is specified within AS/NZS 4233.2 for HPWJ gun

barrels, it is the Procedure of Contract Resources that the length of a HPWJ gun

barrel (including nozzle) should be 48 inches (1.2 metres) and the length of entire

HPWJ gun assembly should be 66 inches (1.65 metres) or as supplied by an

approved manufacturer. Where the length of the barrel/gun cannot comply with

these requirements, a JSEA must be prepared and approved by the Contract

Resources General Manager or their delegate prior to commencement of the job

HPWJ guns must be equipped with a failsafe dead man switch. The “dead man

switch” should be designed such that the operator’s hand is required to initiate

high pressure water flow. Releasing the handle will immediately “dump” pressure

from the gun, dump valve or the pump bypass system. Some guns are fitted with

double triggers which both need to be operated to start the water flow through the

barrel

Note: A dump valve that will immediately dump all the water pressure when the

control is released is the only approved fail-safe control

When lancing, the lance operator must only operate a foot operated fail-safe

control with guard. Only the lance operator (person nearest the working end of

the lance) must operate the fail-safe device

WARNING - At no time should the fail-safe control be tied down or locked

into position. Injury could result if the fail-safe is bypassed or locked



Starter bars, longer in length than the diameter of the pipe will be used when line

moleing. A starter rod is a rigid piece of pipe affixed to a lance or line mole to

prevent reversing of lance/mole in the tube/line. The starter bar must be pressure

rated to the pressure rating of the pump.

When manual line moleing/lancing operations are to be done, an

"anti-withdrawal" device (back out preventor) securely fastened to the pipe MUST

be installed to prevent the removal of the mole nozzle while still under pressure.

No exceptions are permitted.

All operators must carry the HPWJ emergency medical alert card, provided as

part of the instruction course, at all times while jetting

7.1 Housekeeping

During cleaning operations, accumulations of materials may form at the pipe/tube

openings. Work should be stopped and the materials removed when a safe work

position or working surface cannot be maintained. This is particularly important

where the work area is confined, such as platforms and scaffolds and where material

debris may accumulate from the cleaning process.

7.2 Working Surfaces

Blast equipment must be operated from approved work surfaces. Due to excessive

back thrust exerted on the operator when using HPWJ guns, the use of ladders and

"A" frames are not acceptable as work platforms.

8 Equipment Area Preparation

8.1 General Preparations

Warning barricade tape will be placed around the perimeter of the pump and job site.

In addition to the warning tape, a warning sign indicating that “Danger - HPWJ work is

in progress” or a sign with similar warning should be positioned around the work site.

If the job is above ground level, warning tape and/or signs may be required below.

Warning tape and/or signs will be placed along those portions of the high-pressure

water hose that are outside of the barricades where there is the risk of this equipment

being damaged or being a safety hazard to other site personnel.

Remove warning tapes and barricades after completion of a job.

When practical, items to be cleaned should be moved out of congested areas and

away from people.

Electrical equipment must be protected from water damage by being covered (e.g.,

with plastic) or shielded (e.g., by hanging a tarpaulin, etc.) and must be

isolated/racked out.



8.2 Work Location Preparations

The truck/pump location should conform to operations requirements. The location

should be such that the length of hoses required is minimized. Where practical avoid

parking in passage or access ways.

Do not operate a pumping unit inside a building or an enclosed area.

Ensure that adequate working area and a surface that provides good footing is

available before operations begin. Remove any hazard (e.g., oil, grease, and loose

object) from working area.

8.3 Water Supply

Tie-ins to the industrial water supply must be reviewed with client operations

personnel.

Locate the water supply hose so abrasion during operation does not wear the hose

cover and cause the hose to rupture.

Caution should be used when accessing fire mains water for HPWJ operations.

Doing so reduces the volume of available firewater in an emergency, and there may

be a potential health hazard from exposure to potentially contaminated water.

It is preferable to use portable water.

8.4 Permit Requirements

All work authorization must be obtained according to the permitting procedures.

Where HPWJ is to take place in the immediate vicinity of electrical equipment or

wiring which could result in its direct contact with the water stream (e.g., around

equipment where wiring is covered with rubber, oil, insulation, etc.), the equipment is

to be locked out.

8.5 Environmental Considerations

Where the risk of debris/material entering the drainage systems or be an uncontrolled

area, efforts must be made to block off all drains surrounding the cleaning area.

Collecting and disposing of waste material must be an integral part of the project plan.

Water conservation must be considered in a HPWJ project plan. Water recycling

should be considered as part of this.

9 Tool And Machine Requirements

Pre-start safety checks are required each day or when equipment is relocated

The HPWJ equipment operators will check out the operation and condition of all critical

equipment. Prior to commencing HPWJ activities the Checklist to Start and Operate

High Pressure Water Equipment must be completed.



A relief device will be installed on the high-pressure side of the pump, set to relieve at

no higher than the maximum allowable working pressure of the lowest rated

component in the high-pressure system. The device will be capable of limiting system

pressure of the system as per the requirements of AS/NZS 4233 (1999).

Prior to starting a job, the operation of the hand or foot switch should be checked while

flushing the lines of any debris and before adding the correct nozzle. The switch

should relieve pressure immediately without sticking.

Prior to starting a job, the assembled high-pressure components will be gradually and

evenly pressurized to the maximum rated capacity of the system to verify the integrity

of the system and the connections.

All pumps associated with high pressure water cleaning operations must have an

emergency stop device.

One control valve or switch will control only one high-pressure device. (One operator

will operate only one high-pressure lance device, mole, or HPWJ gun at a time.

All high-pressure hoses, including Safety Whips must be inspected and pressure tested

as per the requirements of AS/NZS 4233 (1999). All tested hoses will be stamped by

the testing provider and copies of the relevant test certificate will be retained as per the

hose management procedure.

Any hose used must be pressure rated to the maximum pressure output of the pump

the hose is used on.

All hoses, including the safety whip section of hose will be inspected for damage at the

start of each job by operators responsible for the job.

Hoses will have a burst pressure rating as specified by AS/NZS 4233 (1999).

Hose identified as not fit for use (e.g. damaged wire braid, damaged fittings, kinked,

etc) must not be used and once identified must be rendered unusable (e.g. cut fitting

off, flatten fitting, remove seal cartridge, etc).

High-pressure hoses for use with 1000bar equipment will have M24 fitting connections.

No quick-connect fittings are to be used for this rated equipment.

Quick connect/disconnect fittings are only to be used with the 20K rated equipment.

The filter on the pump suction should be clean and in good operating condition.

Hoses will have restrainer devices attached to prevent hose connection separation.

10 Work Practices

A HPWJ crew will be composed of at least two persons. For safety reasons a crew

member must be available at the pump to de-pressurise it or a remote cut off

switch/device which can de-pressurise the system must be used.

When undertaking the JSEA for the specific job, consideration must be made to the

ergonomic factors for the operator which includes an assessment of static body

position and reaction forces and the person’s fitness for the task. Work should be

scheduled in such a manner to eliminate fatigue or exhaustion of personnel.



Always be sure the pressure being used is not causing damage to the equipment being

cleaned. It is recommended that only minimum pressure to do an adequate job of

cleaning be used.

For maximum safety, no one is to be within 7 meters in any direction of the hydro blast

nozzle(s) or of an operator while HPWJ is in progress particularly when the operator is

manually operating a HPWJ gun or flexi lance. Solid barricades can be used.

When HPWJ equipment where the scale may release explosive vapours, or where a

fine dust condition may exist, the equipment being cleaned will be grounded.

At no time will the foot pedal or dump valve be locked down or jammed in the

pressurized position.

11 Manual Tube Flexi-Lancing

Refer to Contract Resources standard operating instructions for the specific operation

of the equipment being used.

Repetitive application of high pressure water to clean rows and columns of tubes or

pipes. This method requires one or more persons to handle the lances and/or hoses.

A safety device (back-out prevention) must be used at all times to prevent the hose

assembly from being pulled out of the tube or pipe while equipment is energized or

pressurized or to prevent the equipment hydraulicing back out of the tube in an

uncontrolled manner.

11.1 Use Of Mini Moles (Boiler Snakes)

The mini mole is a flexi lance designed for the cleaning of small diameter tubes.

Due to the smaller outside diameter of the lance and nozzle and the flexibility of the

lance, the mini mole is used for tubes that are too small to be cleaned using the

traditional thermoplastic lances.

The outside diameter of the mini mole lance is 0.335”/8.5mm. It can be used to

clean tubes with an internal diameter as small as 0.445”/11.5mm

The mini mole inlet fitting is 1/16” NPT

The outer layer is a double braided stainless steel wire covering

The ferrule and the nozzle are integral to the mini mole lance and cannot be

removed from the lance body

The lances have a working pressure of 8,000psi/552 bar

These lances cannot be pressure tested and have a working life of 12 months

(hose test certificates will define the expiry date of the lance), after twelve months

the lance must be withdrawn from service and sent to Contract Resources

Adelaide for disposal



The use of the mini mole/boiler snakes present their own unique hazards and as

such the following minimum requirements must be met before a mini mole is

used:

Any person using a mini mole must be trained (minimum of IFAP – “Course In

Hydroblasting Induction”) and be experienced in HPWJ activities

A back out preventer must be used with the mini mole

The collets for use with the back out preventer have a gap of 7.5mm, and have

7.5 stamped on each side of the collet. These are specially machined collets for

use with the mini mole. Operators of the mini mole/back out preventer must

monitor the collets and the lance/ferrule/nozzle for wear as the work progresses

to ensure that the mini mole ferrule will catch on the collet and not allow the

ferrule to pass through the collet

A JSEA specifically formulated for the mini mole cleaning task is to be completed

prior to any use of the mini mole

Before any work is undertaken with the mini mole, the General Manager of

Contract Resources must be notified of the intended work and permission

granted prior to the use of a Boiler Snake. The General Manger will review the

JSEA to ensure it covers the relevant hazards and controls

11.2 General Requirements

Always assess if there is a mechanical way to do this job

The use of rigid lance or auto free lance equipment should be considered as the

first option of cleaning tubes and only when this equipment cannot be used,

should manual lancing be considered as an alternative work method

High-pressure water flow to the lance will be actuated by a fail-safe, contact type

switch or valve which when released, causes pressure at the lance to drop to

1bar pressure. The valve or switch must have a guard to prevent inadvertent

actuation

High pressure will be applied to the nozzle only when the lance is in the tube

While moving the lance from one tube to the next, the flexi lance must not be

under pressure

If the opposite end of the equipment being tube lanced is open, a cover or shield

should be installed on the open end to contain the jet spray and water

Do not clean the entrance of a line with the tube lance. Clean this section of pipe

with a HPWJ gun



While tube lancing pipe openings must be properly barricaded, this should be

done in addition to normal barricading preparations covered in this procedure

Do not lance tubes above shoulder level. This reduces the ability of the operator

to control the flexi lance

11.3 Do’s And Don’ts Of Manual Tube Flex Lancing

This method is used where space requirements prohibit the preferred option of rigid

lancing or the use of the auto lance equipment.

Do Do Not

Use back out prevention (anti-

withdrawal) equipment when using

flexi lance equipment

Use a flex hose with frayed reinforcing

braids or one that has been kinked or

structurally damaged in any manner.

Shield the back of the exchanger or

barricade the surrounding area to

protect personnel from the spray and

the potential debris exiting the tubes

Operate above the rated maximum

working pressure of the hose.

Give the operator who is at the tube

sheet inserting the flex lance control

of the foot pedal.

Position yourself where the blast will

spray on you.

Be prepared for back pressure

resulting from plugged tubes.

Pull the nozzle out of a tube until the

pressure is dumped.

Install a starter bar on the end of the

flex hose when cleaning heat

exchanger tubes and attach the self-

propelling nozzle to it.

This pipe extension gives the

operator better control for inserting

and extracting the nozzle from the

tube.



12 HPWJ Gun Jetting

12.1 General Requirements

Only use AS/NZS certified HPWJ gun and attachments, as supplied by the

manufacturers

The HPWJ gun operator should never point the HPWJ gun at himself or anyone

else. Objects being cleaned must not be hand held

Back thrusts can be created by the high-pressure jet stream that can easily put a

person off balance. Only use the minimum pressure required to perform the

cleaning activity or that can be controlled comfortably by the operator

Only use AS/NZS certified nozzles and attachments

Only use attachments that are rated for use with the pump being used on the

cleaning work

Watch for indications of the jets becoming plugged. This can cause unbalanced

thrusts or over-pressuring of the system

Jetting with a fail-safe gun requires the operator(s) to hold the gun while directing

the jet stream at the object or surface to be cleaned

The protective safety measures are mandatory to shield the operator from the

high pressure jet stream



12.2 Do’s And Don’ts Of Safe Gun Jetting

Do Do Not

Clear the work area of light

objects that could be shot by

the action of the high pressure

spray.

Work in areas with poor footing unless

corrective measures are taken. Many

surfaces become slippery when wet, so

special caution should be taken to

eliminate the hazard.

Be sure the nozzle is the proper

size for the pressure and flow

required to perform the clean

activity and for the pump and

equipment involved in the work.

Use unbalanced geometric patterns of

jets - be sure the size and position of the

jets are balanced so the thrust in

opposite directions is equal.

Caution those around you of

the cutting action of the jet

stream.

Under any circumstances tie down the

gun trigger on the gun

Be prepared for the back thrust

created by the high pressure jet

stream.

Forget to watch for indications that a

nozzle is becoming plugged. This can

cause an unbalanced thrust or a

pressure overload on the system. Clean

the nozzle or replace it before

continuing with the cleaning operation.

Prior to jetting, test the lever on

the fail-safe gun to ensure that

it activates smoothly and when

released, the pressure drops

immediately. The lever housing

should be cleaned regularly to

prevent build-up of debris which

might interfere with proper

operation.

Use a gun barrel that is unnecessarily

short. A recommended length of 48

inches (1.2 meter) is suggested for all

possible operations. This helps

eliminate foot and leg injuries which may

result from the gun being pointed at the

operator's body during jetting.



13 Rigid Lancing

Rigid lance equipment in operation

Operation of the machine is performed remotely

High pressure jet lances are normally fabricated from seamless austenitic

stainless steel tubing with a minimum wall thickness of 0.065 in. (1.6 mm). These

tubes usually have threaded fittings welded at each end which permit lances and

nozzles to be changed easily

Lances for cleaning tube bundles are usually held in a range of convenient

lengths. The majority of cleaning operations are carried out using 18 ft., 20 ft. or

22 ft. (5.5, 6, or 7 meters) lances with outside diameters equal to those of the

nozzle being used

Rigid lancing requires the operator to feed the lance into rows of tubing such as

in a heat exchanger and then hydraulically “drive” the lance through the tube

while connected to a high pressure water system which delivers water at high

pressure to the nozzle attachment

In some cases when using long lances or under awkward conditions, the operator

will require assistance in handling the lance



13.1 Do’s And Don’ts Of Rigid Lancing

Do Do Not

Shield the back of the exchanger

or barricade the surrounding

area to protect personnel from

the spray.

Lance tubes above shoulder level.

Elevate the work platform so the

operator can be in a comfortable

stance when operating the

equipment. Failure to do so can

reduce the effectiveness of the

protective equipment and

unnecessarily tire the operator.

Be prepared for hydraulic back

pressure which results from

plugged tubes. When this

occurs, the lance will tend to

back out of the tube. The water

should be dumped immediately

when this happens.

Move the lance from one tube to

another with the water under

pressure. Release the foot valve,

dumping the pressure, then remove

the lance and insert in the next tube

before reengaging the valve. Failure

to do this will expose the operator to

the cutting jets.

Operator of the rigid lance is to

remain in control of the rigid

lance equipment at all times

when the lance is being used.



14 Appendix 1 Checklist To Start And Operate HPWJ



15 Responsibilities

Refer Section 5

16 Associated Documents

Relevant State and Federal Legislation, Standards and Codes of Conduct

HSEQ.PRO.Risk Management and applicable

Standard Operating Instructions specific to the equipment being used

Manufacturer’s maintenance and operation instructions specific to the equipment

being used

17 References

Australian/New Zealand Standard AS/NZS 4233.1 “High Pressure Water (Hydro)

Jetting System

Part 1: Guidelines for Safe Operation and Maintenance; and

Australian/New Zealand Standard AS/NZS 4233.1 “High Pressure Water (Hydro)

Jetting Systems

Part 2: Construction and Performance

Australian/New Zealand Standard AS/NZS 4024 Machine Guarding and Contract

Resources machine guarding procedure.

18 Environmental Impacts And Aspects Statement

Please refer to the appropriate Environmental Impacts and Aspects Statement on

SharePoint



Competency Assessment

No. Questionnaire C/NYC

Q1 When should the fail-safe control be tied down? C / NYC

A1 Never

Q2 Why must hose connections have a secondary joining mechanism?

A2 To prevent whipping

Q3 What is the purpose of the dead man switch?

A3 For the immediate dumping of pressure from the gun

Q4 When lancing, who is responsible for operation of the foot operated fail-safe control?

A4 The Lance Operator

Q5 Identify all 7 PPE items required when hydro blasting?

A5 Hard Hat, Safety Goggles, Face Shield, Hearing Protection, Heavy Duty Rain Suit Or HPWJ Suit, Protective Gloves, Safety Rubber Boots

Q6 Because of the excessive back thrust generated by HPWJ Operations only A frames are acceptable as work platforms true or false?

A6 False

Q7 When is it safe to tie down or lockdown the fail safe control?

A7 Never

Q8 Who is responsible for authorising JSEA’s?

A8 The Supervisor and the client

Q9 What is the only approved fail safe control?

A9 The dump valve



Competency Assessment

Q10 In what scenario would you be required to place barricades and warning signs in excess of 5 metres from the worksite?

A10 When there is a likelihood personnel may be struck by water or debris

Q11 What must be considered when locating the truck/pump?

A11 Minimising the length of the hose

Q12 Quick connect fittings are appropriate to what pressure level?

A12 Less than 20k rated equipment

Q13 How are hose conditions verified?

A13 Through pre start checklists

Q14 Why must minimum crew size exceed two persons?

A14 A crew member must be available at the pump to de-pressurise it or a activate remote cut off switch/device

Q15 What is considered a safe distance between the hydro blast nozzles and an operator while HPWJ is in progress?

A15 7 metres , no one is to be within 7 meters in any direction of the hydro blast nozzle(s) or of an operator while HPWJ is in progress

Q16 In what situation is a solid barricade a must?

A16 Manually operating a HPWJ gun or flexi lance

Q17 Why should lance tubes not be held above shoulder level?

A17 It reduces the ability of the operator to control the flexi lance

Procedure Date

High Pressure Water Jetting

Employee is competent in undertaking this procedure? Yes No

Employee Name : Signature :

Trainers / Assessors Name : Signature :

k AssedfrwrerewRisk AssessmenyRiskRisk Assessment

Procedure

Version No 1.0 Date Last Modified 22/11/2010 3:44 PM Author Mike Fitzpartrick Pages 26 of 28

Audit

Procedure: High Pressure Water Jetting

Date:

Audited by :

Location of Audit: Manager/Supervisor:

Item Question Evidence Sited Comments Conformance Score

0,3,5

1. All technicians have read and understand this procedure

2. A JSEA has been completed prior to commencement of operations

3. Correct PPE is worn at all times?

4. Where manual flexi lancing operations are being conducted a JSEA has been prepared and approved by the General Manager?

5. All HPWJ Operators have successfully completed the IFAP introduction to Hydro blasting Certificate Course?

6. Persons not involved in cleaning are observing the exclusion zone

7. Operating pressure is not exceeding rated pressure of equipment


Audit


Date:

Audited by :



0,3,5

8. Checklist to operate equipment has been completed and signed

9. Appropriate barricading and signage consistent with this procedure is in place?

10. HPWJ Equipment is earthed/bonded?

11. Operators are carrying emergency medical alert card on their persons

12. Hazardous objects have been cleared from work area?

13. There are a minimum of two operators within the worksite at all times?

14. The operator maintains the direction of the gun away from people at all times?


Audit


Date:

Audited by :



0,3,5

15. Appropriate shielding is in place as per the procedure

AUDITOR’S SIGNATURE:

SAFETY REP’S SIGNATURE:

CONFORMANCE SCORE: / 75

CONFORMANCE %:

0 – Non Conformance

3 – Continuous Improvement Opportunity

5 – Total Conformance

high pressure water jetting

Documents

hydro jetting

water supply

contract resources group

machine requirements

intermediate level

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general preparations

general considerations