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UNIT IGC2: CONTROL OF INTERNATIONAL WORKPLACE HAZARDS

Element 1: Workplace hazards and risk control

1. Outline the welfare facilities that should be provided in the building (page no: 1-2) (8)

Drinking water – Access to wholesome drinking water. If non-potable water is also available then

supplies should be clearly labeled to distinguish between the two.

Sanitary conveniences – access to a sufficient number of sanitary conveniences (WCs) for the number

of workers present with separate facilities for men and women. They should be protected from the

weather and adequately clean, lit and ventilated. Special provision should be made for the disabled.

Washing facilities – access to suitable washing facilities by sanitary conveniences, changing facilities

and as required in work areas. Showers may be necessary if the work is dirty, strenuous or involves

potential contamination with hazardous substances. Washing facilities should have hot and cold (or

warm) running water, soap and towels (or other means of drying).

Changing rooms – suitable changing facilities if workers have to change into special work wear and this

involves significant undressing. These should be adequately lit, clean and ventilated, with separate

facilities for men and women.

Accommodation for clothing – lockers or other storage facilities where workers have to change for

work so that their personal clothing can be kept clean and secure. Separate storage for dirty work clothing

may be necessary to prevent cross-contamination.

Resting and eating facilities – access to suitable rest areas where workers can take a break from work.

Such areas should have sufficient seating and be away from hazardous work areas, allowing workers to

remove PPE and relax. Eating facilities should be provided so that food can be eaten in a hygienic

environment. If hot food is not provided at work then basic facilities might be provided so workers can

make their own hot drinks and food.

2. Identify prevention strategies an organization could consider to reduce the risk violence

towards workers. (page no:1-5) (8)

� Collecting and analyzing incident reports.

� Interviewing staff formally or informally.

� Staff surveys.

� Zero tolerance policy and prosecution of offenders.

� Security staff.

� CCTV cameras.

� Security doors between public areas and staff areas.

� Minimize queues and waiting times.

� Clear announcements about waiting times.

� Training for staff, e.g.

� Providing a good quality service.

� Diffusing aggression.

� Screens between staff and public.

� Panic alarms.

� Pleasant environment.

� Preventing violence to workers conducting home visits:

� No lone working or no lone working in certain high risk areas.

� Keeping records of past incidents and vetting customers.

� Visit-logging with supervisor.

� Pre- and post-visit telephone calls.

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� Training for staff, e.g.

� Lone working procedures.

� Break-away techniques (self-defence).

� Always having a means of communication (e.g. mobile phone).

� No visits after dark.

� Parking in secure areas.

� Not carrying cash or valuables.

3. Identify the types of hazard that may cause slips or trips at work. (or) (4)

Identify four hazards that can cause slip and trips. (page no: 1-8) (4)

� Smooth floor surfaces that are inherently slippery (e.g. polished marble) and Wet because of

spills or cleaning operations.

� Contamination of a floor with a slippery contaminant (e.g. fat or leaves).

� Frost and ice (e.g. outside pavements in winter or the floor in a freezer).

� Note that a person’s footwear can make a big difference to how vulnerable they are to slipping on

a floor.

� Uneven or loose floor surfaces (e.g. broken paving slab; poorly-laid floor mat).

� Trailing cables (e.g. the flex of a vacuum cleaner).

� Objects on the floor (e.g. a bag left on the floor).

4. Outline how slips and trip hazards in the workplace might be controlled. (page no: 1-10) (4)

Slip resistance surface: All floor surfaces where people may walk should be designed to ensure an

appropriate level of slip-resistance. (e.g. by applying a non-slip resin to an existing floor).

Spillage control and drainage: Floors and pedestrian routes should be designed and constructed to

withstand foreseeable spillages. Such spillages might simply be of water (e.g. drinks), but in other

instances might be of oil, fuels (e.g. diesel).

Warning signs and boards: Clearly visible and easily understood signs and markings should be provided

so that pedestrians (even those unfamiliar with the workplace) are made aware of hazards and what they

must do to avoid them. Signs should conform to relevant standards.

5. Outline three control measures to segregate pedestrians and vehicles in the work place.

(3)

Vehicle free zones - it may be possible to eliminate the hazard by creating pedestrian only areas.

Pedestrian free zones – since pedestrians are usually the group at greatest risk during vehicle

maneuvering operations, it may be possible to eliminate them from certain parts of the workplace.

Vehicle traffic route layout – good design of roads and routes can be used to keep vehicles at a distance

from pedestrian walkways and other vehicles. One-way systems are an effective method of reducing the

risk of vehicle/vehicle collisions.

6. Identify the main hazards that may be present during the demolition of a building. (page no:1-17)

(8)

� Premature collapse of structures.

� Work at height.

� Plant and machinery.

� Contact with live overheads.

� Contact with buried services.

� Asbestos.

� Dust.

� Movement of vehicles.

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� Explosives.

� Noise and vibration.

� Hazardous substances from previous use of the building.

� Biological hazards from vermin or stagnant water.

� Sharp objects, including glass and nails from the demolition, or syringes left by trespassers.

� Manual handling.

7. A three meter deep trench has to be dug across a car park.

i. Identify hazards associated with the work. (page no:1-33) (10)

� Contact with underground services

� Collapse of the excavation's sides

� Materials falling onto people working in the excavation

� People and vehicles falling into the excavation

� People being struck by plant

� Flooding

� Soil collapse

� Improper access and egress

� Fumes

ii. Outline control measures that could be implemented to reduce the risk. (page no:1-34) (10)

Battering - the sides of the excavation can be sloped back (battered) at an angle that is

sufficiently shallow that the soil will not slip.

Shoring - the sides of the excavation can be supported (shored) with metal or timber that is fixed

in place inside the excavation.

Trench box - the sides of the excavation can be temporarily supported by a metal box that can be

lifted into the excavation and moved along to give a protected work area.

Barriers should consist of guard-rails (as for a scaffold work platform) to prevent people

falling in, and toe boards to prevent objects being kicked down into the excavation.

Good lighting (both within the excavation and at the edges) and signage should be provided.

Long excavations should be provided with crossing points (bridges) that should be similarly

guarded in with barriers and toe-boards.

Access to the excavation should be achieved by properly positioned and secured ladders.

Ladders should extend 5 rungs above the edge of the excavation to give a secure stepping off

point. They should be routinely inspected.

8. Identify EIGHT safe working practices that should be considered to reduce the risk when using a

mobile tower scaffold. (8) (page no:1-30)

� Guard-rail fitted to the work platform.

� Tower must not be overloaded.

� Wheels should be locked when the tower is in use.

� Tower must be sited on firm, level ground.

� People and materials should not remain on the tower when it is moved.

� Care should be taken to avoid overheads when the tower is moved.

� Outriggers should be used where necessary to ensure stability.

� People should not climb up the outside of the tower.

� Tower must be built by trained workers.

9. Repair work is to be carried out on the roof of a school.

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i. Identify control measures to reduce the risks to roof workers. (6)

� Fragile roofs should be clearly signed.

� The safe working method for fragile roofs is usually by the use of roof ladders or crawling

boards.

� These are laid across the roof surface, supported by the underlying load-bearing roof

members, and distribute the load of the worker over a wide area, enabling the roof structure

to sustain the load safely.

� Access equipment must be maintained correctly to ensure stability. This must be carried out

by a competent person and is often subject to statutory requirements,e.g. inspection

frequencies.

� Personal protective equipment, such as harnesses and helmets.

� Health condition of the individuals

ii. Identify TWO control measures to reduce the risks to other persons. (2)

� Construction sites almost always have a risk of falling objects so they should be mandatory

hard hat areas.

� Collective protection systems, such as safety nets and air bags.

� Warning signs

� Barricade the area

10. Identify why accidents may occur in staircase (6)

� Poor lighting

� Not using hand rails

� Not following rules(eg. Running)

� Improper footwear

� Spillages

� Insufficient treads and risers

� Slippery surfaces

11. Identify the factors to consider when assessing the adequacy of lighting within an open plan office.

(page no: 1-2)

� Natural light should be used in preference to artificial light.

� Light levels should be adjusted to suit the level of detail required and the visual acuity of the

workers.

� Local lighting, such as spotlights positioned above machinery, might be required to give higher

levels of light on critical areas.

� Lighting must be arranged to avoid reflections and glare that might dazzle or temporarily disable.

� Lighting must be arranged to avoid the creation of shadows that might obscure areas and create

risk.

� Flickering should be avoided to prevent nuisance and in particular the “stroboscope effect”.

� Lighting must be suitable for the environment (e.g. intrinsically safe lighting used in a flammable

atmosphere).

12. List eight design features or safe practices intended to reduce the risk of accidents on staircases used

as internal pedestrian router within work premises

� Adequate width

� Provision of handrails

� Dimensions of treads and risers.

� Provision of landings.

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� Provisions for disables persons.

� Possibility of using a lift as an alternative.

� Avoid the need to carry large or heavy items up or down stairs

� Appropriate footwear – low heels.

� Provision of non slip surfaces.

13. Identify the safe working practices for the use of a mobile elevating work platform (MEWP) or a

Scissor lift. (In the test book page no:1-30)

• Vehicle sited on firm, stable ground.

• Sufficient clearance from obstructions and overheads when operating.

• Barriers around MEWPs to prevent it being struck by vehicles or mobile plant.

• Barriers also act to keep people out from underneath the cradle.

• Guard-rails incorporated into the cradle. Safety harnesses worn as an additional backup.

• Controls of the MEWP should be inside the cradle so that the person actually working at height

has some control.

• Not driven with the cradle raised unless specifically designed to do so.

• Must not be overloaded.

• Must be inspected as an item of lifting equipment designed to carry people.

• Use restricted to trained, authorized staff only.

14. An independent tied scaffold is to be erected on a building in a busy town centre location.

(a) Outline the precautions that should be taken in order to reduce the risk of injury to members of the

public during erection and use of the scaffold.

• Guard-rail fitted to the work platform.

• Tower must not be overloaded.

• Tower must be sited on firm, level ground.

• People and materials should not remain on the tower when it is moved.

• Care should be taken to avoid overheads when the tower is moved.

• Outriggers should be used where necessary to ensure stability.

• People should not climb up the outside of the tower.

• Tower must be built by trained workers.

(b) Outline the inspection requirements for an independent tied scaffold.

• When they are first erected.

• After any substantial alteration.

• After any event that may affect their stability, e.g.after being struck by a vehicle or after high

winds.

• Periodically (typically weekly).

• Points to check would include:

• Condition of the tubes (especially standards).

• Tying and bracing.

• Condition of the work platform.

• Edge protection (guard-rails, toe-boards).

15. Workers who deal with the public may be subject to violent behavior.

(a) Give the meaning of ‘work-related violence’.

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Any incident in which a person is abused, threatened or assaulted in circumstances relating to their

work.

(b) Identify reasons why a member of the public may behave violently towards a worker.

• Cash handling – any work that involves the handling of quantities of cash or valuables puts workers

at risk of violence associated with robbery.

• Lone working – any lone working that takes the worker into urban areas or puts them in contact with

members of the public at remote or private locations.

• Representing authority – any work where the worker represents authority, such as police, traffic

wardens, etc.

• Wearing a uniform – uniforms are often seen as a symbol of authority, but even where they are not

workers may still be singled out for abuse.

• Dealing with people under stress – when people are under stress they are less capable of handling

their emotions and can lose control.

• Dealing with people under the influence - of drugs and alcohol, or with mental health problems,

when

normal inhibitions on behaviour have been affected.

16. The influence of drugs on workers in the workplace can have a significant effect on health and safety.

(a) Identify possible reasons why a person may be in possession of drugs in the workplace

� Due to work pressure

� Loneliness(work alone)

� Family influence

� Regular habit

(b) Outline control measures that an employer could take in order to reduce the misuse of drugs in the

workplace. . (page no: 1-7)

� Rules restricting access to alcohol in the workplace or during working hours.

� Statutory legal requirements prohibiting workers from being under the influence of drugs and

alcohol.

� Non-statutory requirements prohibiting workers from being under the influence of drugs and

alcohol that have been set by the employer.

� Arrangements for any random drugs and alcohol testing those workers will be subject to.

� Arrangements for workers to have access to rehabilitation and treatment programmes if they

admit to having a problem.

� Disciplinary procedures for workers, who refuse assistance, refuse to be tested or who fail a test.

� Provision of information, instruction and training to workers, supervisors and managers.

17. Identify ways in which accidents may be prevented when using portable ladders as a means of access.

(page no: 1-26)

• Site on a solid, flat base so that the feet do not sink into the ground. Weight should only be

supported on the styles, never on the rungs.

• Angle of the ladder should ideally be 75° to the horizontal or at a ratio of 1:4 distance away

from the wall to height (1 out: 4 up).

• Top of the ladder must rest against a solid support.

• Ideally the ladder should be secured at the top.

• Do not site or handle near live overheads.

• If this is not possible, then guy ropes should be attached and secured to firm supports.

• If this is not possible, ladder should be “footed” by someone standing on the bottom rung.

• Top of the ladder should extend far enough above the level of the working position or the

platform onto which it provides access to provide a safe handhold. The stepping off point should

be safe and clear.

• Only one person should climb on the ladder at any one time.

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• Nothing should be carried in the hands while climbing, so that both hands are free to grasp the

styles.

• Wooden ladders should not be painted as this can hide defects.

18. Emergency rescue procedures should be considered when planning to work at height.

i) Give reasons why a person may need to be rescued when working at height. (4)

• To avoid an accidents in the workplace

• To improve the worker morale

• To comply with law

• To avoid other losses due to an accident

• To improve health and safety culture

ii) Identify methods that could be used to rescue a person when working at height.

(4)

• Safety harness

• Fall arresting system

• Safety nets

• Ropes

• Air bags

19. Office workers are to relocate to new premises. Excluding welfare facilities, Outline factors

associated with the new workplace that should considered when reviewing the health and safety

requirements for the workers.

• Plant layout should be considered.

• Emergency procedures should be implemented

• Fire fighting equipments and their usage procedures

• Vehicles and pedestrians routes

• Machinery guards and safety devices

• Workload should be avoided

20. Identify factors that may increase the risk of injury to workers who need to walk through the

warehouse.

• Unclean floors and walkways.

• Smooth floor surfaces

• Wet because of spills or cleaning operations.

• Contamination of a floor with a slippery contaminant uneven or loose floor surfaces (e.g.

broken paving slab; poorly-laid floor mat).

• Trailing cables (e.g. the flex of a vacuum cleaner).

• Objects on the floor (e.g. a bag left on the floor).

• Pedestrian walkways that require pedestrians to walk in vehicle traffic routes (e.g. in a

warehouse or car park).

• Areas where people have to work adjacent to moving vehicles (e.g. road works; loading

bays).

•Inadequate Lighting for safe movement through a workplace and lights should therefore be

routinely inspected and replaced/repaired as necessary.

• Noise levels should be kept as low as possible to enable pedestrians to hear any communications

(such as tannoy announcements or shouts of warning), alarms (such as a fire alarm) and hazards

(such as approaching vehicles). High noise level in the warehouse will increase the overall risk to

the workers.

•During maintenance activities relating to environmental considerations (lighting, noise, dust)

will increase the risk.

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21. Office workers are to relocate to new premises. Excluding welfare facilities, Outline factors

associated with the new workplace that should considered when reviewing the health and safety

requirements for the workers. (8)

• Plant layout should be considered.

• Emergency procedures should be implemented

• Fire fighting equipments and their usage procedures

• Vehicles and pedestrians routes

• Machinery guards and safety devices

• Workload should be avoided

• Training

• Shift timing/ Working hours

22. Outline the procedure for spillage response

• Raise the alarm and inform emergency service and relevant authorities (eg; fire and rescue

service, water supply authority).

• Evacuate all personnel, seal off access from danger area.

• Quickly assess the nature and extent of the incident.

• Do not approach the liquid if you do not know what it is.

• Raise first aid treatment for those who might have been affected.

• Provide a barrier or some other form of spillage containment such as sand or granules to contain

the spillage.

• Isolate any ignition sources.

• Keep workers away.

• For internal spills with no fire risk, ventilate by opening windows and closing doors.

• For external spills, cover drains to prevent the material going into drains or watercourses.

• Do not wash spillage into drains.

• Issue appropriate PPE to those involved and competent in carrying out the procedure.

• Ensure safe disposal of the spilled substance and any absorbent material used.

Element 2: Transport hazards and risk control

1. Identify measures to reduce the risk to pedestrians and vehicles in the work place. (5)

� As part of the risk assessment, transport hazards must be identified and assessed

� The provision of designated safe crossing points and refuges

� Fitting vehicles with audible or visual alarms for example to give warning of a reversing

operation

� The use of a banksman to ensure safe vehicle movement in areas where pedestrians are likely

to be present

� Ensuring a good standard of visibility by the provision of mirrors, transparent doors and

CCTV

� The introduction of a speed restriction on vehicles; the use of trained and authorized drivers

particularly for forklift trucks

� The provision and use of high visibility personal protective equipment

� Provision of a good standard of lighting which avoids the possibility of glare.

2. Identify precautions that should be taken when leaving a fork-lift truck unattended. (page no:2-4) (6)

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� The first one relates to leaving the forklift truck on a firm level surface.

� Park in a designated area, to ensure that it cannot rollaway.

� The truck must not be left in a position where it could obstruct the emergency exits, walkways or

fire points, and must be parked away from other vehicles.

� The truck should be left with the mast tilted slightly forward and forks resting on the floor to

make sure that it is stable and not likely to overturn.

� The truck must not be left until the break has been applied and the power switched off.

� Park away from other vehicles on a firm, level surface.

� Where a start key is used, the key must be removed and returned it to a responsible person, as

appropriate.

3.

a) Outline why a vehicle may not be able to stop effectively (4)

� Lack of proper / adequate braking system

� Over speeding

� Loss of control of the vehicle.

� Incompetent driver / operator

� Lack of proper maintenance of the vehicle.

� Chance of oil spillage on the road / Slippery Surface

b) Outline activities associated with vehicles when they are not moving that could result in risk

of injury (4) (In Test book go to page 2-2)

� Loading, eg. When doing manual handling jobs like loading crates from a truck

� Unloading eg. When unloading crates from a truck

� Securing – When workers climb onto the vehicle in order to secure the load can lead to

fall hazard.

� Coupling – When vehicles are attached to other towed equipment there is a potential of

collision and crushing.

� Maintenance Work – while doing maintenance work either on top or underneath the

vehicle.

4. Outline the precautions that might be needed to ensure the safety of pedestrians in vehicle

maneuvering areas. (8)

� Segregated systems for vehicular and pedestrian traffic.

� Appropriate road markings.

� Maintaining good visibility (mirrors, provision of lightings etc.,)

� Audible warnings for vehicles.

� The drawing up and enforcement of site rules.

� The provision of refuges.

� The wearing of high visibility clothing.

� A good standard of housekeeping.

� Training for, and supervision of, all concerned.

5. Outline the means by which the risk of accidents from reversing vehicles within a workplace

can be reduced. (page no: 2-4) (8)

� Avoidance of reversing by implementing one way traffic systems.

� Segregation of pedestrians and vehicles or the provision of refuges.

� Good vehicle selection so that drivers have adequate visibility.

� Provision of audible reversing alarms and flashing beacons.

� Provision of mirrors at blind spots to see approaching pedestrians.

� Use of high visibility clothing.

� Ensuring that the area is well lit.

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� Provision of banks men.

� Training for drivers and pedestrians working in the area.

6. Forklift trucks are operating in a busy workplace.

Identify suitable control measures to reduce the risk of collision with workers

� Suitable for their intended use.

� Suitable for the environment and conditions in which they are used.

� Maintained in safe working order.

� Only driven by suitably trained, qualified staff.

� Inspected routinely before use.

� Provision of audible reversing alarms and flashing beacons.

� Provision of mirrors at blind spots to see approaching pedestrians.

7. (a) Identify reasons why a vehicle may not be able to stop effectively.

� No braking system

� Over speeding

� Improper maintenance of brake system

� Loss of control

(b) Outline activities associated with vehicles when they are not moving that could result in risk of

injury. (page no:2-2)

Loading – both manual and mechanical loading of vehicles can create risk, e.g. the manual

handling risk associated with lifting crates into the back of a lorry, or the risk of collision when

loading a flat-bed lorry using a forklift truck.

Unloading – both manual and mechanical unloading can create risk, e.g. tipping operations can

result in the vehicle overturning or people being struck by the material being tipped.

Securing – when workers have to climb onto a vehicle in order to secure the load, e.g. a driver

might have to climb onto the top of a lorry to sheet over the load to prevent it blowing out when

moving at speed, or climb onto the top of a road tanker to close hatches. Both of these operations

involve work at height.

Coupling – when vehicles are attached to trailers or other towed equipment there is potential for

collision and crushing.

Maintenance work – when mechanics have to access various parts of the vehicle and may have

to work at height or under the vehicle.

8. (a) Identify fixed objects that could struck by a moving vehicle in a workplace. (4)

• Buildings

• Walls

• Tower cranes

• Signage

• Barricading

• scaffolding

(b) Outline control measures to reduce the risk of vehicle hitting fixed objects. (4)

• Adequate lighting should be provided inside the workplace

• Convex mirror should be maintained

• Proper sign boards should be installed wherever necessary

• Proper barricading over fixed objects

Element 3: Musculoskeletal hazards and risk control

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1. A worker is manually loading boxes of components onto metal shelves.

a. Identify four types of injury that worker could suffer while carrying out this activity Or List four

specific types of injury that may cause by the incorrect manual handling of loads. (page no:3-7) (4)

� Tendon and ligament injuries

� Muscle injuries

� Hernias

� Work-related upper limb disorders (WRULDs)

� Cuts, burns, dislocation and broken bones

b. Identify factors in relation to the task that will increase the risk of injury. (page no:3-7) (4)

� At what height is the load being picked up, carried or put down

� Is the task very repetitive

� Is there a high work-rate

� Is a long carrying distance involved

� Does the task involve stooping (worker has to keep their legs straight and bend their

back) to move the load

� Does the task involve twisting (turning the shoulders while the feet stay still)

� Can rest breaks be taken as the worker requires them

� Does the task involve lifting the load through a vertical distance

� Does the task involve reaching above shoulder height

� Does the task involve the worker holding the load away from their trunk (torso)

2.

a. Outline a good handling technique that could be adopted by a person required to lift a load from

the ground.(6) (page no:3-10)

Employees should be trained in basic safe lifting technique. This technique minimizes the risk of

musculoskeletal disorders.

� Before lifting

–– Check the weight and stability of the load.

–– Plan the route of the carry.

–– Establish a firm grip.

� The lift

–– Bend the knees and use the leg muscles to lift.

–– Keep the back upright.

–– Keep the load close to the body.

–– Avoid twisting, over-reaching, jerking.

� Setting down

–– Use the same principles as when lifting.

–– Maintain good balance.

–– Set the load down and then adjust its position using body weight.

b. Give TWO examples of how a manual handling task might be avoided. (2)

� Forklift Trucks

� Hoists

� Conveyors

� Cranes

3. Outline the precautions that should be taken when using mobile cranes. (page no:3-18) (8)

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� Ensuring that the load to be lifted is within the safe lifting capacity of the crane – safe lifting

capacity will vary with the length of the jib and the distance away from the crane that the jib is

positioned to (radius), so capacity can vary from one lift to the next.

� Carefully siting the crane on even, stable ground in a safe position away from structures or

overheads that might be struck during the lifting operation.

� Using the outriggers correctly.

� Checking that the crane has been maintained and has a certificate of thorough examination in

accordance with local laws.

� Restricting use of the crane to trained and competent operators only.

� Ensuring that each lift is planned and supervised by a competent person and that the driver and

slinger are competent.

� Providing a banks man to give directions to the crane operator with good means of

communication between driver and other operators.

� Ensuring that safety devices such as overload indicators are operational and are used correctly,

these devices are frequently disabled or ignored by the crane operator.

� Checking that there are no obstructions such as buildings or overhead lines in the vicinity of the

lift.

� Checking weather conditions and obeying any manufacturer’s recommendations about maximum

wind speed.

4. Identify the precautions to be taken when using a mobile elevating platform (MEWP) to reach a high

point as a streetlight. (8) (page no: 1-30)

� Vehicle sited on firm, stable ground.

� Sufficient clearance from obstructions and overheads when operating.

� Barriers around MEWPs to prevent it being struck by vehicles or mobile plant.

� Barriers also act to keep people out from underneath the cradle.

� Guard-rails incorporated into the cradle.

� Safety harnesses worn as an additional backup.

� Controls of the MEWP should be inside the cradle so that the person actually working at height

has some control.

� Not driven with the cradle raised unless specifically designed to do so.

� Must not be overloaded.

� Must be inspected as an item of lifting equipment designed to carry people.

� Use restricted to trained, authorized staff only.

5. Battery powered fork-lift trucks are used to move materials in a warehouse lift trucks.

a. Identify FOUR hazards associated specifically with battery-powered fork lift trucks. (page no: 3-

15) (4)

� Charging batteries emit hydrogen gas which is explosive.

� Batteries contain dilute sulphuric acid which is corrosive.

� Batteries are extremely heavy and present a manual handling risk if they have to be

changed for charging purposes.

� The electricity can cause arcing, shock, burns or fire.

� Battery contents are an environmental hazard requiring appropriate disposal.

� Battery-powered vehicles can be very quiet or almost silent, increasing the risk of

collision with pedestrians.

� Battery leads can short and result in burns and electric shock.

b. Outline the means by which the risk of accidents from reversing vehicles within a workplace can

be reduced. (page no: 2-4) (8)

� Avoidance of reversing by implementing one way traffic systems.

� Segregation of pedestrians and vehicles or the provision of refuges.

� Good vehicle selection so that drivers have adequate visibility.

� Provision of audible reversing alarms and flashing beacons.

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� Provision of mirrors at blind spots to see approaching pedestrians.

� Use of high visibility clothing.

� Ensuring that the area is well lit.

� Provision of banks men.

� Training for drivers and pedestrians working in the area.

6. Outline the specific causational factors that may have contributed to Work Related Upper Limb

Disorders. (page no:3-8)

Manual handling risk assessment focuses on four main factors:

� The task.

� The load.

� The environment.

� Individual capabilities

The task:

� At what height is the load being picked up, carried or put down

� Is the task very repetitive

� Is there a high work-rate

� Is a long carrying distance involved

� Does the task involve stooping (worker has to keep their legs straight and bend their

back) to move the load

� Does the task involve twisting (turning the shoulders while the feet stay still)

� Can rest breaks be taken as the worker requires them

� Does the task involve lifting the load through a vertical distance

� Does the task involve reaching above shoulder height

� Does the task involve the worker holding the load away from their trunk (torso)

The load: The load can be assessed by asking questions such as:

� How heavy is the load?

� How large and bulky is the load?

� Is the load an easy shape to lift?

� How stable is the load?

� Where is the centre of gravity (C of G) of the load?

� Is the load difficult to grip? (or does it have handles)?

� Is the load hot, sharp or otherwise hazardous?

The Environment: The environment can be assessed by asking questions such as:

� Are there restrictions on the space available?

� Is the floor surface slippery or uneven?

� Are there changes in floor level (steps, stairs, etc.)?

� What are the light levels like?

� What is the temperature and humidity?

The Individuals: Individual capabilities can be assessed by asking questions such as:

� Does the activity require unusual ability? Some handling activities require unusual

strength, stamina, size or technique.

� Does the activity present significant risk to vulnerable individuals such as pregnant

women or people with pre-existing back injuries?

7. Outline the measures that can be taken to reduce the risk of Work Related Upper Limb Disorders.

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� Control repetitive handling by introducing frequent rest breaks or job rotation to

minimize the length of time that an individual worker has to perform the task.

� Eliminate stooping and twisting by changing the layout of the workstation.

� Use a table or lift to bring the load to waist height to eliminate picking up from floor

level.

� Break down a heavy load into smaller parts.

� Use several workers to handle a large, bulky load rather than just one.

� Stabilize an unstable load by securing it or putting it into a container.

� Mark up a load with an off-centre C of G so that workers can see where the C of G is.

� Attach handles to a load that is difficult to grasp.

8. Outline the main factors to be considered when doing an ergonomic assessment of a DSE workstation.

(page no: 3-2)

Task Factors:

� Repetition – the need for repetitive movements when carrying out the task (e.g. typing for several

hours).

� Force – the physical force required to perform the task and the strain this puts on the body (e.g.

closing stiff catches on a machine).

� Posture – any requirement to adopt an awkward posture (e.g. stooping over into a bin to pick out

contents).

� Twisting – any twisting action required by the task (e.g. twisting the wrist when using a

screwdriver).

� Rest – the potential for the worker to rest and recover from any fatigue (e.g. a worker on a

production line cannot stop the line; they have to keep working even when fatigued).

Environment Factors: � Lighting – the availability of natural and artificial light and the effect on the worker’s ability to

see the work clearly. The presence of glare may also cause a problem.

� Other environmental parameters – in particular temperature, humidity and ventilation will directly

affect the worker’s ability to perform the task and their comfort.

Equipment Factors: � Equipment design – the shape of the equipment and how this affects ease of use (e.g. a large,

shaped handle on a scraper makes it easier to hold and use).

� Equipment adjustability – the scope there is for the user to adjust the equipment to suit their

personal requirements (e.g. the height of the seat for a computer user)

9. Identify the features of a chair to ensure it is suitable for use at a DSE workstation.

� The chair is suitable

� The chair is stable

� The chair is adjusted correctly

� The user is aware if how to adjust the chair

� There is proper back rest

� Seat height adjustment

� Swivel mechanism

� Seat back height and tilt adjustment

10. Outline the possible risks to health associated with the use of display screen equipment (DSE).

(page no: 3-3)

WRULDs – associated with repetitive use of the keyboard and mouse for long periods of time.

Eye strain – temporary eye fatigue associated with prolonged use of the screen.

Back pain – and other MSDs associated with sitting in a fixed position, perhaps with poor

posture, for long periods of time.

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Fatigue and stress – associated with the type of work being done, e.g. call centre staff may be

Subjected to verbal abuse during telephone calls.

11. An engineering workshop uses an overhead crane to transport materials.

(a) Identify reasons why loads may fall from this crane. (2)

• Overloading.

• Improper lifting technique.

• No Training for workers and supervision.

(b) Outline precautions that should be taken in order to prevent accidents to workers at ground

level when overhead cranes are in use. (6)

� Ensuring that the load to be lifted is within the safe lifting capacity of the crane – safe lifting

capacity will vary with the length of the jib and the distance away from the crane that the jib is

positioned to (radius), so capacity can vary from one lift to the next.

� Carefully siting the crane on even, stable ground in a safe position away from structures or

overheads that might be struck during the lifting operation.

� Using the outriggers correctly.

� Checking that the crane has been maintained and has a certificate of thorough examination in

accordance with local laws.

� Restricting use of the crane to trained and competent operators only.

� Ensuring that each lift is planned and supervised by a competent person and that the driver and

slinger are competent.

� Providing a banks man to give directions to the crane operator with good means of

communication between driver and other operators.

� Ensuring that safety devices such as overload indicators are operational and are used correctly,

these devices are frequently disabled or ignored by the crane operator.

� Checking that there are no obstructions such as buildings or overhead lines in the vicinity of the

lift.

� Checking weather conditions and obeying any manufacturer’s recommendations about maximum

wind speed.

Element 4: Work equipment hazards and risk control

1. Identify the Mechanical hazards related with the work equipment. (page no: 4-8,9,10)

� Crushing

� Shearing

� Entanglement

� Cutting or severing

� Drawing in or trapping

� Impact

� Friction or abrasion

� High pressure fluid injection

2. Outline the precautions that should be taken in order to ensure the safety of employees carrying out

maintenance work on process equipment.

� Maintenance should only be carried out by competent staff.

� Ensure isolation of power source is confirmed.

� Stored power should be released or secured to prevent accidental discharge.

� Where power cannot be isolated live parts should be covered with insulating materials.

� Use of personnel protective equipment which are insulated like rubber gloves.

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� Running of dangerous moving parts at low speed when need to work in live machines.

� Provision of maintenance guards which are allowing access to required areas only.

� Use of handling aids to prevent chance of manual handling.

� Use of a safe system of work like permit to work to be implemented

3. Identify precautions that would need to be considered before welding work can commence.

� Maintain a safe workplace - If possible, move the material to be welded or cut to a safe location

designated specifically for welding and cutting.

� Keep fire hazards away- Areas for welding, cutting, and heating must be kept clear and free of

flammable liquids and solvents.

� Provide fire barriers - If welding or cutting cannot be performed in a designated location or away

from combustible materials, provide metal sheets or a fire-resistant screen to prevent heat, sparks,

and slag from reaching these materials.

� Be alert for cracks or crevices - Sparks and slag can travel long distances.

� Provide fire extinguishing equipment - Be prepared to put out fires. Service-able fire

extinguishers, fire hoses, or sand buckets should be on hand.

� Consider the need for a fire watcher - Operators may not become aware of a fire starting while

welding or cutting.

� Know the local fire codes for welding and cutting.

� Inspect the work area after completing operations - Make sure there are no hot sparks or hot metal

which could start a fire later.

� Before welding or cutting in a new location for the first time, please do the risk assessment. They

may know of some serious fire hazard that might otherwise be overlooked.

4. Outline control measures to reduce the risk to workers when using non-powered hand tools.

� Tools must be suitable for the task that they are going to perform and for the environment in

which they are to be used, e.g. non-sparking tools (do not produce sparks when struck) is suitable

for use in a potentially flammable atmosphere.

� Users should be given appropriate information, instruction and training. Many workers serve

some form of apprenticeship or spend several years in training where they acquire an

understanding of safety in the use of the tools for their trade, but not all workers come to the

workplace with this knowledge (which may seem like common knowledge to others).

� Tools should be visually inspected routinely before use to ensure they are in an acceptable

condition. This should be done by the user. Spot checks by line management will ensure that

users comply. Substandard tools should be maintained or discarded.

� Tools should be maintained in a safe condition, e.g. blades should kept sharp and handles firmly

attached.

� Supervision is important to ensure that safe working practices are adhered to and misuse does not

become commonplace.

5. a. Identify the hazards that could be faced by the worker who is using a petrol-driven strimmer to

maintain roadside grass verges.

� Contact with the moving parts of the strimmer

� The possibility of being struck by flying stones or other materials

� Slips / Trips / Falls

� Manual handling hazards

� The danger posed by moving traffic, noise and vibration

� Dust and fumes.

� The hazards associated with the storage and transfer of petrol.

� Weather condition like exposure to ultraviolet radiation

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b. List the five items of personnel protective equipment that should be provided to the worker who is

engaged in using petrol driven strimmer to maintain roadside grass verges.

� Ear defenders

� Eye protection

� Respiratory protection

� Gloves

� Safety footwear

� Gaiters

� High visibility jackets

c. Outline measures other than the use of protective equipment that might be necessary to ensure the

health and safety of the worker who is engaged in using petrol driven strimmer to maintain roadside

grass verges.

� The use of traffic control or barriers

� The selection and maintenance of equipment to reduce to a minimum the levels of noise

and vibration

� The provision of information, instruction, training and supervision and health

surveillance

� Completion of a risk assessment for the job to be done

6.

a. Identify four hazards associated with the use of bench top grinder. (4)

� Abrasion on contact with rotating abrasive wheel.

� Drawing in at nip-point between wheel and tool rest.

� Ejection of parts of the wheel during normal use or if it bursts.

� Entanglement with the spindle on which the wheel is mounted.

� Electricity.

� Hot parts caused by friction (especially the workpiece being ground).

� Health hazard from dust.

� Noise and vibration.

b. Other than a guard, Identify four control measures that could be introduced to reduce risk to a

worker using a bench top grinder. (4)

� Secure grinder in position.

� Tool rest adjusted to minimise nip point between rest and wheel.

� Use and setting restricted to trained operators only.

� Eye protection (impact resistant).

� Hearing protection may be necessary.

� Installation of LEV may be required to control dust.

� Routine maintenance, including inspection and portable appliance testing for electrical

safety.

� Regular checks of the grinding wheel.

� Regular checks to ensure correct grinding material has been selected.

c. Outline the basic requirements that you would consider when selecting a guard or safety devices

for a bench top grinder. (4)

� The guard or safety device should be suitable for the machinery

� The guard should reduce the accident rate rather than increasing the accident rate

� Select standard guard or safety device and it should be easy to use.

� The guard should be tamper proof.

� The guard should not obstruct the working cycle of the machine if required in such

operations.

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7. Outline the merits and limitations of (page no:4-12)

i. an interlock guard

Merits: The guard is intended to allow frequent access to a machine or danger zone by removing

the power source and preventing the equipment from operating while the guard is open. When a

guard is removed a safety interlock system prevents machine operation For example, a

microwave oven has a hinged door on the front to allow easy access; this door is interlocked so

that power to the microwave generator is shut off when it is open.

Limitations: The main limitation of an interlocked guard is that it is possible to bypass the system so

that the machine can be operated with the guard open. With simple interlock systems this is easily

done, but even complex interlock systems can be defeated by a determined person. The dangerous

parts or machinery may not be at rest as the equipment is opened, and this may put the operator at

risk (though this can be overcome by good design and consideration of “run down” times).

ii. a trip device

Merits: Trip devices are intended to minimise severity of an injury and are often used as an

additional control measure, e.g. in combination with an interlocked access gate to ensure that an

operator does not gain access by climbing over a fence or being locked in by a colleague.

Limitations:

Do not provide a physical barrier to prevent access. Can be over-ridden, e.g. using

platforms to span a pressure mat. May not operate fast enough to prevent harm (but may reduce

the severity). May be overly sensitive, leading to frequent trips and production delays which will

encourage the operator to bypass or disable them. Frequent trips may result in operator stress.

8. Outline four main categories of guards and safeguarding devices that may be used to minimize the

risk of contact with the dangerous parts of machinery. (8) (page no:4-12)

Fixed Guards: A fixed guard is a physical barrier that prevents a person from coming into contact with

dangerous moving parts.The guard may by shaped to fit the machine quite closely (enclosing

guard), or it may be more like a fence around the machine (perimeter guard). It may have

openings in it (e.g. to allow raw material to be fed into a machine),but these must be designed in

such a way that it is not possible to reach in and contact dangerous parts (distance guard).

Adjustable Guards:

An adjustable guard can be set to a range of positions by the operator depending on the

nature of the workpiece and the operation being carried out. For example, the top guard on a

bench-mounted circular saw can be set at a range of heights depending on the size of wood being

cut.

Interlock Guards:

An interlocked guard is a protective device designed to be removed as a normal part of

routine machine operation. The guard is intended to allow frequent access to a machine or danger

zone by removing the power source and preventing the equipment from operating while the guard

is open. When the guard is removed a safety interlock system prevents machine operation. For

example, a microwave oven has a hinged door on the front to allow easy access; this door is

interlocked so that power to the microwave generator is shut off when it is open.

Trip Devices: Trip devices are protective devices that do not put a physical barrier between the operator

and the dangerous parts of machinery. Instead some form of sensor is used to detect the presence

of the operator and stop the machine. Trip devices are intended to minimise severity of an injury

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and are often used as an additional control measure, e.g. in combination with an interlocked

access gate to ensure that an operator does not gain access by climbing over a fence or being

locked in by a colleague.

9. Identify four mechanical hazards presented by pedestal drill & outline in each case how injury may

occur. (page no:4-17)

� Entanglement with the rotating drill bit or chuck.

� Stabbing or puncture by the drill bit during normal use or if the bit breaks.

� Puncture by swarf ejected during metal cutting.

� Impact if struck by the workpiece if the bit jams and the workpiece rotates.

� Drawing in at nip-points between motor and drive belts.

� Electricity.

� Noise.

� Hot parts (especially the drill bit).

� Health hazard from cutting fluid (e.g. dermatitis).

10. (a) Identify hazards associated with the use of a cement mixer.

� Entanglement with rotating drum or drive motor.

� Drawing in at nip-point between motor and drive mechanism.

� Crushing between drum and drum stop when tipping.

� Friction or abrasion on contact with moving drum.

� Electricity.

� Ergonomics and manual handling injuries during loading.

� Health hazard from cement dust inhalation (irritant) and contact with wet cement

(corrosive).

� Hazards due to the fuel (electricity or petrol).

� Being struck by vehicles operating in the area.

(b) Outline control measures that can be used to reduce the risks of injury to operators of a

cement mixer.

� Location of the mixer on firm, level ground.

� Location away from traffic or where traffic is controlled.

� Fixed guards to motor and drive mechanism.

� Routine inspection and portable appliance testing, and use of residual current device

(RCD) for electrically powered equipment.

� Safe storage of petrol and control of ignition sources for petrol-powered equipment;

avoid use in confined spaces due to emission of exhaust gases.

� Reduction in manual handling or positioning of cement bags close to the equipment.

� Use restricted to trained operators only.

� Hand protection, respiratory protection, overalls and eye protection (splash resistant).

� Hearing protection to reduce noise exposure.

11. Outline four control measures to reduce the risk of injury from pedestal drill

� Fixed guards over motor and drive mechanisms.

� Adjustable (possibly interlocked) guard over chuck and drill bit.

� Clamp to secure workpiece to base.

� Eye protection (impact resistant).

� Hearing protection may be necessary.

� Routine maintenance, including inspection and portable appliance testing for electrical

safety.

� Use restricted to trained operators only.

12. In a factory conveyor system is used to transfer manufactured articles to the warehouse area.

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Identify the control measures to be taken to reduce the risk of injury to workers from the conveyor.

� Fixed guards on drums

� Enclosure of conveyed items by side guards

� Trip wires, if necessary , along the full length of the conveyor

� Emergency stop buttons

� Safe access at regular intervals

� Avoid loose clothing

� Restrict access

� Wearing bump caps

� Regular maintenance by competent workers

13. A factory producing furniture uses wood in the manufacturing process and is concerned about the

health risk of wood dust.

a. Identify operations which are likely to produce high levels of wood dust in the workplace. (4)

� Sawing

� Routing

� Planning

� Turning

� Cleaning items or areas with compressed air lines

b. Identify health risk which could be associated with the wood dust. (4)

� Dermatitis

� Allergic respiratory effects

� Mucosal

� Non-allergic respiratory effects

c. Outline control measures which could reduce the risk from the wood dust. (12)

� Installing Local Exhaust Ventilation

� Provide Respiratory Protective Equipment

� Provide other Personal Protective Equipment

� Good standards of Housekeeping

� Vacuum cleaning equipment should be maintained properly

� Washing facilities for workers

� Separate storage for workers clothing and laundering

� High standard of personal hygiene by changing overalls and washing hands before

eating and drinking.

13.Identify non-mechanical hazard associated with machinery and give an example in each case.(8)

� Electricity-Contact with damaged wire leads to electrocution

� Noise- working near to generator

� Vibration- Working with drilling machine

� Hazardous substances-Bio medical waste, Asbestos

� Ionising radiation-Gammaray like Ir 192

� Non-ionising radiation- UV by sunlight

Element 5: Electrical safety

1. Identify the possible effects of electricity on the body. (page no: 5-2)

� Electric shock – severe electric shock can cause involuntary muscle grip, heart

fibrillation, respiratory failure and cardiac arrest.

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� Burns – burns can also result from an electric shock, at the point of contact and at the

point that the current flows out of the body. There may also be internal burns along the

current path.

� Fire and explosion.

� Arcing.

� Secondary effects.

2. Outline four factors that may affect the severity of injury from contact with electricity (page no: 5-3)

Several factors influence the severity of injury associated with receiving an electric shock:

Voltage – as Ohm’s law shows there is a simple relationship between voltage and current, the higher

the voltage, the greater the current.

Duration – the length of time that a person is exposed to the flow of electricity is critical. For

example, a current flow of 60 mA for 30 milliseconds (30 thousandths of a second) is unlikely to

cause a severe injury, whereas the same current flow over a period of 2 seconds can induce VF and

prove fatal.

Frequency – of the AC current.

Current path – the route that the electricity takes as it flows through the body is also critical. If it

runs through the chest it is likely to affect the heart.

Resistance – as Ohm’s law shows there is a simple inverse relationship between current and

resistance - the higher the resistance the lower the current. Most of the body’s resistance to the

passage of electricity is because of the skin. A person with dry skin has a resistance of about 100,000

ohms, but if their skin is wet or damaged this reduces dramatically to 1000 ohms. Any clothing that

the person is wearing will also affect their resistance to the passage of electricity.

Contact surface area – the more skin that is in contact with the live surface, the lower the resistance

and the more severe the injury.

Environment – any environmental factors that reduce resistance will cause an increase in current

flow and therefore increase the severity of the shock, e.g. wet surfaces, humid air, metal surfaces, etc.

3. In relation to the use of electrical cables and plugs in the workplace identify four examples of faults

and bad practices that could contribute to electrical accidents.

� Using unsuitable equipment, e.g. the use of non-intrinsically safe equipment in a

flammable atmosphere.

� Using equipment in wet, damp or humid conditions.

� Misuse, e.g. sticking wires directly into a socket rather than using a plug.

� Physical abuse, e.g. pulling the plug out by tugging at the flex; carrying the tool by the

flex; allowing the flex to be pinched, trapped or crushed, driving over the flex, etc.

� Repairs carried out by unauthorized personnel or carried out badly, e.g. split flex taped up

with insulating tape.

� Continued use of faulty, defective equipment.

� Chemical damage to the flex, e.g. by corrosive wet cement.

� Lack of routine inspection, testing or maintenance.

4. Explain how earthing can reduce the risk of receiving an electric shock. (page no: 5-8)

Earthing is a way of protecting equipment so that in the event of an electrical fault, current flows

safely to

earth rather than flowing through a person who might be touching the equipment. The earth wire of an

item of electrical equipment is usually connected to the outer metal casing or chassis of the equipment. If

a fault develops and the casing or chassis becomes live then a current will flow down this earth wire.

Electricity always takes the path of least resistance, and since the earth wire will have very low resistance

the majority of fault current will flow safely to earth through the wire. Any person touching the casing

will receive a minor shock

22

5. Outline the emergency actions to take if a person suffers a severe electric shock.

The action of discovering a person having suffered an electric shock should be to make others

aware of the situation and, at the same time or immediately afterwards, to turn off the supply. If this is not

possible, and the victim is still in contact with, or in close proximity to, the live part, then he/she should

be pushed clear using a non-conductive implement (such as a broom). First-aid should then be

administered, which, depending on the condition of the person, may include cardio-pulmonary

resuscitation. If successful, an airway should be maintained by placing the victim in the recovery position

and breathing should be monitored until medical help arrives.

6. Outline the practical measures to reduce the risk of injury from electricity when using a portable

electrical appliance on a construction site. (page no: 5-5)

� Consider the use of battery-powered equipment.

� Consider the use of reduced and low voltage (110v) equipment centre tapped to earth.

� Provide increased protection through the use of an RCD.

� Locate cables carefully, away from hazards, e.g. vehicles which may drive over them.

� Consider the use of double insulated equipment.

� Carry out pre-use checks of the equipment for signs of damage.

� Train operators in safe use of the equipment.

� Avoid using in wet conditions (unless the equipment and supply cables are suitable for this).

� Implement a programme of routine visual inspection and thorough testing of electrical

equipment and cables.

7. In relation to electrical safety, explain the meaning of the following terms:

(i) ‘isolation’ (2)

it refers to shutting of the electrical supply to an item of equipment or part of an item

of equipment or part of an electrical system and preventing inadvertent reconnection

in order, for instance, to carry out maintenance work.

(ii) ‘earthing’ (2)

this means whereby electrical equipment and conductive items are connected to earth

by a cable or metal pope work such that the route to earth provides the path of least

resistance to a current flowing under fault conditions.

(iii) ‘reduced low voltage ‘ (2)

Commonly used on construction sites, involves the reduction of local supply voltage

by a transformer to a lower, safer voltage – typically 110 or 55volts.

(iv) ‘overcurrent protection’. (2)

A method of preventing the flow of excess current by cutting the supply under fault

conditions by means of a fuse or circuit breaker.

8. Identify the electrical hazards that could be discovered by a visual inspection. (8)

� Worn cable

� Max current capacity exceeded

� Overheating

� Defective Equipment

� Exposed electric cable

� Misuse of electrical equipment

� Failure to follow safety instruction

� Incorrect fuse rating

� Poor connections

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� Bad circuit connections

9. Outline precautions that should be taken in order to prevent electrical contact when:

(a) Excavating near underground cables (4)

� Excavate by using area map to avoid any contact with underground utilities.

� Permit to work system to be followed

� Isolate the power supply before excavation

� Avoid manual excavation

� Use proper PPE’s if manual excavation is permitted

(b) Working in the vicinity of overhead power lines (4)

� Isolating the power supply when working near power lines. If power cannot be isolated, it

may be possible to sleeve low voltage power lines.

� Using permit systems to control access into danger areas.

� Using barriers, signage and goal posts to keep plant and vehicles a safe distance from

powerlines.

� Using banks men when plant is manoeuvring near power lines.

� Using non-conducting equipment, such as fiberglass ladders.

10. Outline practical measures to reduce the risk of injury from electricity when using portable

electrical tools. (8)

� Consider the use of battery-powered equipment.

� Consider the use of reduced and low voltage (110v) equipment centre tapped to earth.

� Provide increased protection through the use of an RCD.

� Locate cables carefully, away from hazards, e.g. vehicles which may drive over them.

� Consider the use of double insulated equipment.

� Carry out pre-use checks of the equipment for signs of damage.

� Train operators in safe use of the equipment.

� Avoid using in wet conditions

� Implement a programme of routine visual inspection and thorough testing of electrical

equipment and cables.

12. Identify issues to consider when assessing the strength and capability of portable electrical

equipment.

� Age of the equipment

� Usage time

� Working environment

� Standard of equipment

� statutory requirement

� Usage procedure

� Type of work to be carried out.

Element 6: Fire safety

1. Explain using a suitable sketch, the significance of a ‘fire triangle’.

(In Test book go to page 6-1)

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Fuel Any combustible material or substance

Oxygen Consumed during combustion when it is chemically combined with the fuel.

Heat A heat or ignition source is essential to start the combustion process.

2. Identify four methods of heat transfer and explain how EACH can cause the spread of fire.

(In Test book go to page 6-2)

Conduction: Where heat is transferred through a conducting material (e.g., metal), without the conductor

itself is burning.

Convection: As the hot air and gases rise from the fire, cooler air is drawn in which, in turn, his heated

and rises. The continuous process of air being drawn in and heated, then rising, cooling and

descending, forms circulating currents which enable the fire to spread.

Radiation: Heat energy from the fire, in the form of infrared radiation, is transmitted through the air

and may be absorbed by other fuel sources causing them to heat up, possibly enough to

cause ignition.

Direct burning:

Combustible materials in direct contact with naked flame.

3. Outline measures that should be taken to minimise the risk of fire from electrical equipment.

(In Test book go to page 6-11)

� Measures such as the proper selection of equipment to ensure its suitability for the task, pre-

use inspection by the use, establishing correct fuse ratings, ensuring circuits and sockets are

not overloaded, disconnecting or isolating the equipment when it is not in use, and ensuring

that electric motors do not overheat (e.g. by checking that vents are uncovered).

� Additional measures include the need to uncoil cables (particularly extension leads) to prevent

the buildup of heat and protecting cables from mechanical damage.

� Importantly, electrical equipment and systems should be subject to regular inspection, testing

and maintenance by competent persons.

� This should ensure, for instance, that contacts are sound, thereby reducing the likelihood of

electrical arcing.

4. List eight ways of reducing the risk of a fire starting in a workplace.(In Test book go to page 6-9)

� Flammable materials are removed from the work area.

� Items that cannot be removed are covered with fire- retardant blankets.

� The floor is swept clean.

� Any wooden floor is damped down.

� A suitable fire extinguisher is at hand.

� A “fire-watcher” is present in the area.

� The work area is visited routinely after the work has finished to check the area for

smouldering.

� Ensure that workplace is well ventilated.

� Store and use required minimum volume only.

� Use away from heat and ignition sources.

5. List the five steps in doing an assessment on fire risks. (In Test book go to page 6-5)

� Identify the fire hazards: Sources of fuel, ignition, Oxygen.

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� Identify the people who might be harmed (people in the premises and special consideration to

vulnerable people).

� Identify and implement the fire precautions that are required,

� Fire prevention

� Prevention of the spread of smoke and flames

� Fire detection and alarm.

� Means of escape

� Sign and notice.

� Lighting.

� Record findings, plan and train

� Review and revise the assessment as necessary.

6. Outline the requirement to ensure the safe evacuation of persons from a building in the event of a fire.

(In Test book go to page 6-16)

� The means of raising the alarm

� An acceptable distance to the nearest available exit

� Escape routes of sufficient width

� Clear signing of escape routes

� The provision of emergency lighting

� Escape routes kept clear of obstructions with the fire door closed to prevent the spread of

smoke.

� The provision of fire-fighting equipment

� The appointment of fire marshals

� Procedures for the evacuation of those with a physical impairment

� The need to practice the evacuation plant at regular intervals.

7. Outline the general duties of a fire marshal in case of an emergency evacuation in a work place in the

event of a fire.(In Test book go to page 6-20)

Fire Marshal might be required to:

� Check all areas in the building to ensure that everyone knows that evacuation is in progress

and to help where necessary.

� Give special assistance to the disabled and infirm.

� Fire marshal is responsible for coordinating the fire evacuation plan.

� He should organize fire instruction, training, drills and coordinates the evacuation at the time

of the fire.

� He should be made known to workers and they should clearly identifiable at the time of

emergency.

� Fire marshal appointment contributes employers’ commitment.

� He is the vocal point to assist authorities.

� By appointing fire marshal, the employer fulfills the legislation requirements.

8. Identify the classification of fires and the associated fuel sources.

(In Test book go to page 6-1)

Class A - Solid materials , usually organic, such as paper, wood, coal and textiles.

Class B - Flammable liquids, such as petrol, oil and solvents.

Class C - Gases, such as methane, propane and acetylene.

Class D - Metals such as aluminium or magnesium.

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Class F - High temperature fat and oils such cooking fat fire.

9. Identify eight common causes of fires in the workplace. (In Test book go to page 6-3)

� Hot work

� Careless actions and accidents

� Discarded lighted cigarette end or match

� Smoldering waste

� Poor electrical connections

� Overloading electric circuits and using fuse rates too high a rating

� Failure to report and repair faulty equipment promptly

� Defective machinery or equipment

� Deliberate ignition

� 10. Identify the sources of ignition that should be taken into account when storing and using

flammable solvents. (4)

� Hot works,

� Heat energy generated during chemical reaction,

� Electrical heat energy,

� Arcing, friction,

� Naked flames,

� Static electricity,

� Sunlight etc

11. Identify extinguishing agents that can be used on fires that involve flammable solvents and give their

mode of action.

� DCP Fire extinguisher –It prevent the contact between Fuel and oxygen

� Foam type fire extinguisher - It prevent the contact between Fuel and oxygen

� CO2 type- Removal of oxygen.

� SF6-Removal of oxygen contact.

� HFC- Removal of oxygen contact.

12. Other than the provision of extinguishing agents, outline precautions that should be taken in order to

minimize risk when storing and using flammable solvents. (10)

� Flammable materials are removed from the work area.

� Items that cannot be removed are covered with fire- retardant blankets.

� The floor is swept clean.

� Any wooden floor is damped down.

� A suitable fire extinguisher is at hand.

� A “fire-watcher” is present in the area.

� The work area is visited routinely after the work has finished checking the area for smoldering.

� Ensure that workplace is well ventilated.

� Store and use required minimum volume only.

� Use away from heat and ignition sources.

13. Outline control measures that may be needed to help ensure that persons with sensory impairments

and/or physical disabilities may be evacuated safely in the event of fire.

Identify individuals with disabilities and the people assigned to assist them in the Emergency

Action Plan. Provide the person with a nominated assistant to support their speedy escape, like

with the use of a specially designed evacuation chair to enable them to make their way out of

building down emergency exit stairs. Always ask disabled people how you can help before

27

attempting any rescue technique or giving assistance. Ask how they can be assisted or moved,

and if there are any special considerations or items that need to come with them. Provide with a

refuge adjacent to the stairwell for a wheel chair user above ground level in a multi storey

building. Give verbal instructions or information for visual impairment like elevators cannot be

used and give visual instructions to advise of safest route or direction by pointing toward exits or

evacuation maps for hearing impairment. Provision should be made to ensure that an emergency

exists, by special alarm arrangements that cater for their disability, for example, a visual or

vibrating alert for the hearing impaired.

Element 7: Chemical and Biological health hazards and risk control

1. A factory uses small quantities of various toxic chemicals which re obtained from & returned to a

central storeroom.

a) Outline FOUR possible routes of entry of toxic substances into the body & in EACH case, describe

a circumstance in which the storeroom staff might be at risk of such exposure.(page no:7-4)

Ingestion – the substance is taken in through the mouth and swallowed down into the stomach and

then moves on through the digestive system. This is a less significant route of entry since people are

unlikely to deliberately swallow a hazardous substance. Ingestion usually occurs by cross-

contamination (of the hands by a toxic substance) or by mistaken ingestion.

Absorption through the skin – the substance passes through the skin and into the tissues beneath

and then into the blood stream. Only some substances (e.g. organic solvents) are able to permeate the

skin in this way, but when they can this route can be very significant since any skin contact allows

absorption.

Injection through the skin – the substance passes through the skin barrier either by physical

injection (e.g. a needle-stick injury) or through damaged skin (cuts and grazes). This route is

significant for many biological agents (e.g. hepatitis).

Inhalation – the substance is breathed in through the nose and mouth and down into the lungs. This is

a significant route of entry for many hazardous substances in the gas, vapour, mist, fume or dust form.

People have to breathe; if the hazardous substance is present in the air around them then it will be

inhaled. Dust can be inhaled through the nose and mouth in this way, but not all dust will travel down

into the lungs. Dust is made up of small particles of various diameters. Large dust particles are filtered

out by the lungs’ defence mechanisms before they can travel down into the lungs; smaller particles are

not trapped by these defences and will travel deep into the lungs.

b) Identify the factors to consider when assessing the health risk to storeroom staff from handling

the chemicals. (page no: 7-7)

� The hazardous nature of the substance present – is it toxic, corrosive, carcinogenic,etc.?

� The potential ill-health effects – will the substance cause minor ill-health or very serious

disease and will these result from short-term or long-term exposure?

� The physical forms that the substance takes in the workplace – is it a solid, liquid, vapour,

dust, fume, etc.?

� The routes of entry the substance can take in order to cause harm – is it harmful by

inhalation,ingestion, skin absorption, etc.?

� The quantity of the hazardous substance present in the workplace – including the total

quantities stored and the quantities in use or created at any one time.

� The concentration of the substance – if stored or used neat or diluted, and the concentration in

the air if airborne.

� The number of people potentially exposed and any vulnerable groups or individuals – such as

pregnant women or the infirm.

� The frequency of exposure – will people by exposed once a week, once a day or

continuously?

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� The duration of exposure – will exposure be very brief, last for several hours or last all day?

� The control measures that are already in place - such as ventilation systems and PPE.

c) Identify the control measures that might be required in order to minimize the risk to the health of

those working in the store room. (page no:7-14,15)

� Minimization of emission, release and spread of hazardous substances through design and

operation of processes and task activities.

� Effectiveness and reliability of control options that minimize the escape and spread of

hazardous substances.

� Exposure control to be proportional to health risk.

� Personal protective equipment (PPE).

� Other PPE and clothing

� Personal hygiene and protection regimes.

� Health and medical surveillance

2. Identify possible routes of entry of biological organism into the body.

� Mother to child

� Interchanging of body fluids

� Ingestion

� Injection

� Inhalation

� Absorption

3. Outline control measure that could be used to reduce the risk of infection from biological

organisms. (page no:7-23)

Sterilization and disinfection – this process removes the biological agent and therefore the hazard. It is

often used to treat wastes to make them safe for disposal, e.g. treatment of used laboratory equipment,

contaminated medical supplies, etc. Disinfection of workrooms and benches is an important control to

minimise the spread of infectious materials.

PPE can be used to prevent contamination of clothing (e.g. lab coats), or to prevent materials entering

the body (e.g. respiratory and eye protection to prevent entry via inhalation or absorption, gloves to

prevent contact with broken skin). Those handling biological agents should ensure that open wounds

are covered at all times.

The use of microbiological agents can often be restricted to a designated area, e.g. the use of

microbiological safety cabinets (similar to laboratory fume hoods in principle but filtered to prevent

the escape of agents) is common place; however if the agent is on a host, such as an animal, then

quarantine areas may be needed.

Spill containment methods which prevent release of agents are required. Spill trays may be used in

laboratories, whilst uncontrolled releases of, for example, body fluids such as blood may be treated

with a chemical to contain and disinfect.

High standards of personal hygiene are essential – smoking, drinking, eating and applying cosmetics

should all be banned in the workplace, and clothing should be changed (e.g. lab coats removed) before

entering uncontaminated areas.

Finally vaccinations may be used to prevent infection in some instances, e.g. the hepatitis B

vaccinations for first aiders already mentioned.

4. A worker is engaged in general cleaning a large veterinary Clinic.

a) Identify FOUR specific types of hazard that the cleaner might face when undertaking the

cleaning.

FOUR specific types of hazards can be: � Cleaning workers are at risk of exposure to zoonoses, infectious diseases that spread from

animals to humans. Possible routes of transmission include aerosol, droplet spray, ingestion

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(oral), direct contact, indirect contact. Sources of exposure include animals, body fluids,

contaminated tools, surfaces, or other objects in the environment.

� Cleaning workers are exposed to additional biological hazards especially from the animal

droppings which may contain a contagious disease.

� Different chemical hazards including glutaraldehyde and other disinfectants, hazardous drugs,

latex , pesticides, and waste anesthetic gases exist in the veterinary clinic. Exposure to these

chemicals may occur by dermal contact and/or inhalation (being breathed in)

� Workers may be exposed to blood borne pathogens while cleaning the blood of animals

� Additional hazards may include slip while cleaning the biological and /or chemical spills

b) Outline the precautions that could be taken to minimize the risk of harm from these hazards

Following precautions can be adopted at a workplace:

� Personal hygiene practices are the best way to protect the workers from exposed hazards

� Hand washing routines and use of hand sanitizers to be made part of workers daily job

routines

� Double bag all the chemical waste, partially filled vials, undispensed products, needles and

syringes, gloves, gowns, mats and contaminated materials from spill clean ups and animal

bodily fluids

� Prohibition of eating, drinking and smoking in the workplace

� Health Surveillance of the workers to be carried out for health monitoring and biological

monitoring

� Sterilisation to be carried out to treat wastes to make them safe for disposal

� Disinfection to be carried out immediately for the work room and benches to minimize the

spread of infectious materials

� Vaccinations may be used for the workers in some instances e.g. hepatitis B

� Post the sign to warn employees that they are working in an environment where hazardous

drugs are being handled

� Train workers to recognize and understand the risks of working with hazardous chemicals

used as drugs and the biological hazards they are going to face while cleaning

� Training for the use of spill kits followed by the mock drills for the spills at workplace to

make workers trained how to deal with the spill

� Cleaning workers should be part of the dedicated team who carry out the spillage control at

the workplace

� Use of proper personal protective equipment which include but not limited to specialized

gloves, safety shoes (only for cleaning not to be worn outside), coveralls, safety goggles, hair

nets etc.

5. A company produces a range of solid and liquid wastes, both hazardous and non-hazardous. Identify

the arrangements that should be in place to ensure the safe storage of the wastes prior to their

collection and disposal. (page no:7-29)

� The hazardous nature of the waste – the waste may be inherently hazardous to staff involved

in handling it, e.g. toxic or radioactive. This may require the use of PPE.

� The waste may present a manual handling risk.This might be overcome by the use of

mechanical

� handling equipment or handling aids.

� Storage equipment such as skips, bins and compactors may be difficult to access and may

require steps or platforms to allow safe use.

� Waste containers/skips should be stored on concrete surfaces and not on unstable or unmade

ground (grass or earth) to prevent contamination of ground and groundwater.

� Compactors will have moving parts that must be effectively guarded to prevent access.

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� Collection vehicles such as skip lorries present a significant hazard when manoeuvring,

especially when reversing (use a banksman).

� The waste may present a temptation to scavengers (e.g. waste metals) and to vandals

(unlocked storage tank valves) and so must be secured.

� Stored liquid waste should be contained in either a double-skinned container or the vessel

should be contained in a bund.

� Containers should be located away from bund walls.

� Bunds should have the capacity to store 110% of the volume of the largest container in the

bund.

� Provision should be made to empty the bund of rainwater if the storage area is outside (or a

roof installed to prevent rainwater ingress).

� Where liquids are pumped, transferred or decanted the transfer points or tanker connections

should also be contained in a bunded area or the operation carried out over a drip tray.

� Bunds may need to be protected from damage, e.g. by vehicles such as tankers approaching

to make deliveries.

� Bunds will need to be checked and maintained to ensure that they do not leak.

� Any escape may have the potential to cause pollution. Adequately securing the waste might

control this risk, but emergency spill or release plans may also be required, along with the

necessary personnel, equipment and training to put these plans into effect (see Topic Focus).

� Waste types (streams) must be segregated to prevent the mixing and contamination of one

type of waste with another. This usually requires separate secure storage for each type of

waste and the clear identification of types.

� Appropriate documentation should accompany the waste and the duty of care, to dispose of

waste in line with legal requirements, must be fulfilled.

6. Outline the precautions to ensure the health & safety of persons engaged in spray painting activities in

a motor vehicle repair shop.

� As proper ventilation is important when working with paint coatings, a spray booth is an

excellent way to remove spray paint vapors and debris from a worker’s breathing zone

� To provide maximum protection, the spray booth must be properly maintained, including

regular cleaning of filters and overspray

� When painting in an enclosed space (a room),provide outside ventilation air with fans or open

windows & turn off ignition sources like wall heaters

� The air-purifying type of respirator should be used only during exposure to those specific

chemicals, or groups of chemicals, described on the respirator cartridge. While the

atmosphere-supplying type of respirator must be used in some paint spraying operations,

particularly with urethane paints or when painting in a confined space e.g. inside a tank.

Other PPE to be used can be eye googles and coveralls.

� Some of the chemicals you work with can injure skin or cause dermatitis. Coveralls and

gloves prevent these chemicals from coming into contact with your skin, reducing the risk of

damage. Wear your coveralls and gloves whenever working with chemicals. Clean your

gloves and wash your coveralls regularly to prevent chemicals from accumulating, especially

around the cuffs where they can easily come into contact with your skin. As an additional

protective measure, use BARRIER CREAMS on your hands, face and neck. Check to make

use you have the correct barrier cream for the chemicals being used.

� Because of the danger of fire and explosion where paints which contain flammable solvents

are being used, care should be taken to remove all potential sources of ignition before starting

work. This means naked flames, cutting and welding torches, gas fired heaters and materials

which may give off sparks, whether electrical, mechanical, friction or static, and there must

be no smoking. Make sure the correct types of fire extinguishers are available at the work site

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� Many painting projects require preparation of the materials to be painted. Preparation often

involves sanding of the surface which creates a health hazard if dust masks are not worn.

Ideally dust collection systems should be used to prevent large amounts of small particulates

from entering the air. Sanding and scraping of old paint may hold additional hazards if the old

paint contains lead.

� Understand the information given with the material safety data sheet of the paint been used.

For most people who work with a material, there are sections of the MSDS that are more

important than others. You should always read the name of the material, know the hazards,

understand the safe handling and storage requirements, and understand what to do in an

emergency.

� Hazard Communication Standard (HAZCOM) needs to be implemented at the work place.

The Hazard Communication standard requires employers to; maintain an inventory of

hazardous materials, provide employees training on the potential hazards associated with a

material, obtain and maintain MSDSs for each material onsite, establish proper methods and

types of labels, and inform contractors of the hazards that their employees may be exposed to

in their work area

� Step ladders are commonly used for painting. Ladder safety begins with selecting the right

ladder for the job and includes inspection, setup, proper climbing or standing, proper use,

care, and storage. This combination of safe equipment and its safe use can eliminate most

ladder accidents

� One of the most common health hazards associated with exposure to solvents is dermatitis.

This can be avoided by use of substitute solvents which are less hazardous to health

� Use of safety signage with no smoking, no welding to be posted

� Grounding of all spraying equipment

7. Identify the sources of information which could be used in the assessment of risk to toxic substances.

(page no:7-7)

� The hazardous nature of the substance present – is it toxic, corrosive, carcinogenic,etc.?

� The potential ill-health effects – will the substance cause minor ill-health or very serious

disease and will these result from short-term or long-term exposure?

� The physical forms that the substance takes in the workplace – is it a solid, liquid,

vapour,dust, fume, etc.?

� The routes of entry the substance can take in order to cause harm – is it harmful by inhalation,

ingestion, skin absorption, etc.?

� The quantity of the hazardous substance present in the workplace – including the total

quantities stored and the quantities in use or created at any one time.

� The concentration of the substance – if stored or used neat or diluted, and the concentration in

the air if airborne.

� The number of people potentially exposed and any vulnerable groups or individuals – such as

pregnant women or the infirm.

� The frequency of exposure – will people by exposed once a week, once a day or

continuously?

� The duration of exposure – will exposure be very brief, last for several hours or last all day?

� The control measures that are already in place - such as ventilation systems and PPE.

8. Identify the sources of information available in Material Safety Data Sheet. (page no:7-8)

� Identification of the substance or preparation and supplier – including name, address and

emergency contact phone numbers.

� Composition and information on ingredients – chemical names.

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� Hazard identification – a summary of the most important features, including adverse health

effects and symptoms.

� First aid measures – separated for the various risks, and specific, practical and easily

understood.

� Fire-fighting measures – emphasizing any special requirements.

� Accidental release measures – covering safety, environmental protection and clean-up.

� Handling and storage – recommendations for best practice, including any special storage

conditions or incompatible materials.

� Exposure controls and personal protection – any specific recommendations, such as particular

ventilation systems and PPE.

� Physical and chemical properties – physical, stability and solubility properties.

� Stability and reactivity – conditions and materials to avoid.

� Toxicological information – acute and chronic effects, routes of exposure and symptoms.

� Ecological information – environmental effects, which could include effects on aquatic

organisms, etc.

� Disposal considerations – advice on specific dangers and legislation.

� Transport information – special precautions.

� Regulatory information – overall classification of the product and any specific legislation that

may be applicable.

� Other information – any additional relevant information (e.g. explanation of abbreviations

used).

9. Explain the difference between acute and chronic health effects. (4)

Acute Effect: Is an immediate or rapidly produced, adverse effect, following single or

short term exposure to an offending agent which is usually reversible.

Chronic Effect: Is an adverse health effect produced as a result of prolonged or repeated

exposure with a gradual or latent, and often irreversible, effect that may often go

unrecognized for a number of years.

10. Identify the factors affecting the suitability of Respiratory Protective Equipment. (page no: 7-20)

� Concentration of the contaminant and its hazardous nature.

� Physical form of the substance, e.g. dust or vapor.

� Level of protection offered by the RPE.

� Presence or absence of normal oxygen concentrations.

� Duration of time that it must be worn.

� Compatibility with other items of PPE that must be worn.

� Shape of the user’s face and influence on fit.

� Facial hair that might interfere with an effective seal.

� Physical requirements of the job such as the need to move freely.

� Physical fitness of the wearer.

11. Identify factors that could reduce the effectiveness of Local Exhaust Ventilation. (page no: 7-16)

� Poorly positioned intake hoods.

� Damaged ducts.

� Excessive amounts of contamination.

� Ineffective fan due to low speed or lack of maintenance.

� Blocked filters.

� Build up of contaminant in the ducts.

� Sharp bends in ducts.

� Unauthorised additions to the system.

33

12. Outline two types of cellular defence mechanisms that the body has as a natural defence system.

(page no: 7-12)

Respiratory Defences The respiratory system is made up of the nose and nasal cavity, windpipe (trachea) and lungs. The

air passes down the bronchi and bronchioles to the alveoli. These are small air sacs and are the

area where oxygen enters the bloodstream.

The respiratory system is protected by the following defences:

The sneeze reflex:Filtration in the nasal cavity (which has a thick mucus lining that

particles stick to). This is very effective at removing large particles; only particles less than 10

microns in diameter pass through.

Ciliary escalator – the bronchioles, bronchi and trachea are lined with small hairs (cilia).

Mucus lining these passages is gradually moved by these cilia up out of the lungs. Any particles

trapped in this mucus are cleaned out of the lungs by this mechanism. This filtration mechanism

is effective at removing all particles larger than 7 microns in diameter.

Macrophages – scavenging white blood cells that attack and destroy particles that lodge

in the alveoli (where there are no cilia to extract them).

Skin Defences The skin forms a waterproof barrier between the body and the outside world. It is made of two

layers, the outer epidermis and the inner, thicker dermis. Defence mechanisms include:

• A thick layer of dead cells at the surface of the epidermis that are constantly being replenished

as they wear off.

• Sebum – an oily fluid secreted onto the surface of the skin that has biocidal properties.

13. Give the meaning of the term ‘Maximum allowable concentration’.

(In Test book go to page 7-13)

The maximum exposure to a biologically active physical or chemical agent that is allowed during

an 8-hour period (a workday) in a population of workers, or during a 24-hour period in the

general population, which does not appear to cause appreciable harm, whether immediate or

delayed for any period, in the target population. (OR) Exposure concentration not to be exceeded

under any circumstances.

14.(a) Explain the health risks associated with exposure to the leptospira bacteria. (page no:7-26)

The disease leptospirosis starts with flu-like symptoms (fever, headache, and muscle pain) and

then progresses to a more serious phase involving jaundice. At this stage the disease is causing liver

damage and may be known as Weil’s disease. If diagnosed early the disease is usually treated

successfully. It can prove fatal, especially if diagnosed late.

(b) Identify the workplace circumstances where leptospira bacteria may be present. (page no:7-26)

� Leptospira bacteria commonly infect animals such as rats,mice, cattle and horses.

� Infected rats pass the bacteria in their urine, perhaps onto wet surfaces or into water where the

bacteria can stay alive.

� If contaminated water comes into contact with cuts or grazes, or is ingested, then infection

may occur.

� Occupations at risk are those who work with potentially infected animals (e.g. dairy farmers)

or in wet areas where there may be rats (e.g. sewer workers, water sports instructors)

(c) Identify precautions that will reduce the risks from exposure to leptospira bacteria. (page no:7-26)

� Preventing rat infestation, by good housekeeping and pest control.

� Good personal hygiene (e.g. hand-washing).

� PPE (especially gloves).

� Covering cuts and grazes.

� Issuing workers with an “at risk” card to be shown to the worker’s doctor (physician) to allow

early diagnosis.

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16. A dust produced during a work process contains a substance that is classified as toxic and has been

assigned a workplace exposure limit.

a) Give the meaning of the term ‘Toxic’. (page no:7-2) (2)

Toxic – small doses cause death or serious illhealth when inhaled, swallowed or absorbed

via the skin (e.g. potassium cyanide (KCN)).

b) Give the meaning of the term ‘Workplace Exposure Limit’. (page no:7-12) (2)

Maximum concentrations of airborne contaminants, normally measured across particular

reference period of time, to which employees may be exposed.

c) Identify the Limitations of WEL. (6)

� Whenever exposure to the hazardous substances is such that an identifiable disease or adverse

health effect may be linked to the exposure

� Whenever there is an increase in registration of occupational illness and health cases at a

work place with a probability that the work is affecting the health of employees

� After there is a change in the work activities and these activities pose additional hazards to

health of employees working in the hazardous environment

� Whenever the Local Exhaust Ventilation Systems installed is working effectively

� After a major accident which has caused the employees to be exposed to hazardous

environment above the permissible limit

� After the independent third party carrying out health surveillance at the workplace and shows

that the exposure limits are above maximum allowable concentrations

17. (a) Identify the health risks associated with exposure to silica dust. (1)

� Silicosis

� Breathlessness

� Chest pain

� Heart and lung failure

(b) Identify the workplace circumstances where silica dust may be present. (2)

� Mining

� Quarrying

� pottery

� Construction industries

(c) Outline precautions that will reduce the risk from exposure to silica dust. (4)

� Prevention of exposure by use of alternative work methods

� Dust suppression by water jet/spray

� Local exhaust ventilation

� Respiratory protective equipment

� Health surveillance

Element 8: Physical and Psychological health hazards and risk control

1. Explain the following terms in relation to noise exposure at work.

a) Noise-induced hearing loss.

b) Tinnitus

(In Test book go to page 8-1)

a) Noise-induced hearing loss

- Noise induced hearing loss is normally caused by prolonged exposure to high noise levels

causing damage to the hair cells and leading to a permanent threshold shift at particular

frequencies, which worsens with continued exposure both in terms of the extent of the

threshold shift and of the frequencies affected.

b) Tinnitus

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- Tinnitus on the other hand is typified by a ringing or similar sound in the ears caused by

over-stimulation of the hair cells. It can be acute or chronic, permanent or intermittent.

2. Identify four limitations of personnel hearing protection as a means of protecting against the effects of

noise or identify the factors that are likely to affect the performance of personnel hearing protection.

(In Test book go to page 8-4)

Ear Muffs � Uncomfortable when worn for long time.

� Must be routinely inspected, cleaned and maintained.

� Efficiency may be by long hair, spectacles or earrings.

� Incompatible with some other items worn (e.g. spectacles)

� Needs dedicated storage facility.

Ear Plug

� Difficult to see when fitted, so supervision and enforcement difficult.

� Risk of infection if dirty or if cross-contaminated when inserted.

� Interface with communication.

� Effectiveness decreases with usage.

� Need to be correctly sized to fit the individual.

3. Outline four types of engineering control that may be used to reduce noise in the workplace giving an

example of each. (In Test book go to page 8-4)

Source: Eliminating or reducing noise at the design stage e.g. nylon bearings instead of metal.

Substitute the source: Change the noise source for something else that does the same job but generates less noise

(e.g. change a petrol-driven machine for an electric version).

Silencing: An attachment is fitted to the exhaust of a machine the baffles reduce the noise.

Damping: Reduction in structure born noise by use of rubber/cork, springs etc in noise path e.g.

panels, motors etc or by reducing vibration.

Isolation:

Protection of persons from noise source by distance or sound proofed rooms.

Lagging:

On pipes carrying steam or hot mud’s insulation of pipes to reduce sound transmission.

Absorption: Absorbing sound in the work area by means of acoustic absorbent panels on walls or

ceilings

Enclosure:

Placing a sound-proof cover over the noise source.

4.

(a) Outline control measures that can be taken to reduce the noise from cement mixers to which

workers on a construction site are exposed. (4)

� Location of the mixer on firm, level ground.

� Location away from traffic or where traffic is controlled.

� Fixed guards to motor and drive mechanism.

36

� Routine inspection and portable appliance testing, and use of residual current device

(RCD) for electrically powered equipment.

� Safe storage of petrol and control of ignition sources for petrol-powered equipment;

avoid use in confined spaces due to emission of exhaust gases.

� Reduction in manual handling or positioning of cement bags close to the equipment.

� Use restricted to trained operators only.

� Hand protection, respiratory protection, overalls and eye protection (splash resistant).

� Hearing protection to reduce noise exposure.

(b) Identify other noise hazards that may be present on construction sites. (4)

� Grinding activity.

� Welding activity

� Vehicles moving

� Excavation

� Scaffolding

4. In relation to ill-health effects from the use of vibrating hand held tools identify the typical symptoms

that might be shown by affected individuals. (In Test book go to page 8-7)

� Hand-Arm Vibrating syndrome (HAVS)

� Vibration White Finger (VWF)

� Nerve Damage

� Muscle weakening

� Joint damage

5. Outline the control measures that may be used to minimize the risk of health effects caused by using

the vibrating hand held tools. (In Test book go to page

8-8)

� Eliminate the source

� Reduce the vibration at source.

� Substitute the source.

� Changing work techniques.

� Periodical Maintenance

� Interrupt the pathway from source to receiver.

� Isolation of vibrating parts.

� Limit the duration of exposure.

� Job rotation

6. For each of the following types of non-ionizing radiation, identify a source and state the possible ill-

health effects on exposed individuals.

a) Infrared Radiation.

b) Ultraviolet Radiation (In Test book go to page 8-12)

a) Infrared Radiation

Red hot steel in a rolling mill, Fire or furnaces and glass manufacture- redness and burns to the

skin; retinal burns, development of eye cataracts over time.

b) Ultraviolet Radiation

welding operations, Sun - redness and burns to the skin (e.g. sunburn), pain and inflammation to

the surface of the eye leading to temporary blindness known as photokeratitis(often called arc-eye

or snowblindness),increased risk of skin cancer, premature aging of the skin.

37

9. Identify the general methods for protecting people against exposure to non-ionizing radiation.

(In Test book go to page 8-13)

� Shielding

� Increasing the distance between source and person

� Reducing the duration of exposure

� Appropriate personal protective equipment

� The use of barrier cream.

� By following Safe system work / permit to work system.

� Change the competent person often to reduce the impact.

10. Outline the factors that may lead to unacceptable levels of occupational stress amongst worker.

(In Test book go to page 8-15)

� Excessive demands of the job in terms of workload, speed of work and deadlines

� Frequent changes in the working pattern (e.g. changing shift patterns)

� Exposure to noise & vibration

� Extremes of temperature and or humidity

� Cramped conditions

� Dirty or untidy working conditions

� Workplace layout resulting in a lack of privacy or security

� Poor lighting

� Problems with glare

� Inadequate ventilation resulting in stale air

� Inadequate welfare facilities

� Those working outside, inclement weather conditions

12. A number of workers who are required to work with vibrating hand-held tools for lengthy periods

during a work shift have reported symptoms of tingling and numbness in their fingers. Further analysis

has indicated that the workers concerned could be showing early symptoms of hand-arm vibration

syndrome (HAVs).

(a) Outline further symptoms that might develop should the work continue. (4)

� Vibration white finger (VWF)

� Nerve damage

� Muscle weakening

� Joint damage

(b) Outline factors to consider when assessing the risk of HAVS developing amongst the workers. (8)

� To estimate a worker’s actual exposure

� Calculate what the equivalent 8 hour exposure

� Workers health condition

� Type of equipment used

� Total shift timing

� Environmental condition

� Rest timing

(c) Outline precautions that could be taken in order to minimise the risk of the workers developing the

condition.

� Eliminate the source

� Substitute the source

� Changing work techniques

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� Maintenance

� Isolation

� Limit the duration of exposure

� Change the work schedules

� Training is an essential control measure.

Some other important questions:

1. (a) Identify possible effects on the health of workers from exposure to excessive noise at work.

� Temporary reduction in hearing sensitivity as a result of short duration exposure to

excessively loud noise.

� Temporary ringing in the ears as a result of short duration exposure to excessively loud

noise.

� Noise induced hearing loss (NIHL) – permanent loss of hearing as a result of repeated

exposure to excessively loud noise.

� Tinnitus – persistent ringing in the ears as a result of repeated exposure to excessively

loud noise.

� Stress effects - caused by irritating nuisance/ background noise.

� When people are exposed to excessively loud noise the hearing mechanism itself is

damaged.

(b) Give reasons why personal hearing protection may not provide the level of protection stated

by the manufacturer.

� Workers feeling uncomfortable while using for the long time

� If they fail to inspect those equipments periodically

� Improper storage of HPE

� Due to cross contaminations during storage or usage

� Used for long period of time(i.e) more than one year

� Using damaged equipments will reduce the level of protection

� Used in above excessive noise level

(c) Outline the control measures that an employer can take to encourage workers to wear hearing

protection.

� Employees should be involved in selection of HPE

� Displaying precautionary sign

� Explaining the consequences regards to not using HPE

� Showing some videos, case studies

� Motivational programmes for workers

� Safety campaign to be conducted periodically

� Rewards and awards for the workers

2. Outline control measures that could be implemented in order to reduce the risk of pedestrians in

a warehouse where separate traffic routes cannot be provided.

� Segregated systems for vehicular and pedestrian traffic.

� Appropriate road markings.

� Maintaining good visibility (mirrors, provision of lightings etc.,)

� Audible warnings for vehicles.

� The drawing up and enforcement of site rules.

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� The provision of refuges.

� The wearing of high visibility clothing.

� A good standard of housekeeping.

� Training for, and supervision of, all concerned.

3. Outline control measures that may be needed to help ensure that persons with sensory

impairment and/or physical disabilities may be evacuated safely in the event of fire.

� A worker with some hearing impairment might be capable of hearing the audible fire

alarm in their work area, so no special arrangements are required.

� A profoundly deaf worker might not be able to hear the audible alarm, in which case a

visible alarm (flashing light) might be used in conjunction with the audible alarm

� Buddy system might be adopted where a colleague alerts the worker to the fire alarm

� Technical solution might be sought involving a vibrating pager.

� A wheel-chair user above ground level in a multistoreybuilding might be provided with a

refuge adjacent to the stairwell. They might then be helped down the stairs by nominated

responsible individuals, perhaps with the aid of an “evac-chair”.

4. Employers are required to have arrangements in place to prevent access to dangerous parts of

machinery or to stop dangerous parts if a person enters a danger zone. Describe the principles of

operation of:

(a) Sensitive protective equipment(trip devices)

Trip devices are protective devices that do not put a physical barrier between the operator and the

dangerous parts of machinery. Instead some form of sensor is used to detect the presence of the

operator and stop the machine. Trip devices are intended to minimise severity of an injury and are

often used as an additional control measure, e.g. in combination with an interlocked access gate to

ensure that an operator does not gain access by climbing over a fence or being locked in by a

colleague.

(b) Two hand controls

These are a way of protecting the machine operator’s hands where operation of the machine can

only be achieved when two start buttons are pressed at the same time. The idea is that the

machine will only operate when the operator has both hands on the controls.

(c) Interlock guards

An interlocked guard is a protective device designed to be removed as a normal part of routine

machine operation. The guard is intended to allow frequent access to a machine or danger zone

by removing the power source and preventing the equipment from operating while the guard is

open. When the guard is removed a safety interlock system prevents machine operation. For

example, a microwave oven has a hinged door on the front to allow easy access; this door is

interlocked so that power to the microwave generator is shut off when it is open.

(d) Protective appliances

Protective appliances are pieces of equipment that allow an operator to keep their hands away

from dangerous parts. They include clamps, jigs and push-sticks.

5. Outline the precautions that should be taken in order to prevent electrical control when

(a) Excavating near underground cables

� Excavate by using area map to avoid any contact with underground utilities.

� Permit to work system to be followed

� Isolate the power supply before excavation

� Avoid manual excavation

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� Use proper PPE’s if manual excavation is permitted

(b)Working in the vicinity of overhead powerlines

� Isolating the power supply when working near power lines. If power cannot be isolated, it may be

possible to sleeve low voltage power lines.

� Using permit systems to control access into danger areas.

� Using barriers, signage and goal-posts to keep plant and vehicles a safe distance from power

lines.

� Using banksmen when plant is manoeuvring near power lines.

� Using non-conducting equipment, such as fiberglass ladders.

6.

(a) Outline reasons why a person could be injured when using mobile elevated working platform.

� Improper ground condition

� Unprotected edge

� Overturning of MEWP

� Vehicle collision

� Bad weather condition

� uninformed movement

� collide with adjacent or overhead obstruction

(b) Outline precautions to reduce the risk of injury when using MEWP.

� Never drive with raised cradle

� Avoid overloading

� Guard rails should be fitted properly

� Sufficient clearance from obstructions

� Vehicles sited in firm ground condition

� Periodic maintenance and inspection to be done

7. Outline how the following two protective measures reduce the risk of electric shock and, in each

case, give an example of its application.

(a) Reduced voltage

The lower the voltage that an electrical system is operated at, the lower the risk of injury

associated with electric shock. This is because of the relationship that exists between voltage and

current as indicated by Ohm’s law. As voltage is reduced, so the shock current is reduced and the

severity of injury reduced.

Ex. Using 230 V is high risk, by using step down transformer we can reduce the voltage by 110

V, so that the risk is low.

(b) Double insulation

There are two layers of insulation between the user and any live conductors. This eliminates the

need to provide earth protection, so double-insulated equipment will have a two-core flex: live

(hot) and neutral only. Double insulation is commonly used as the means of protection for hand-

held portable electrical equipment such as hedge trimmers.

8. Outline the precaution that should be taken for the routine maintenance of machinery (8).

� Maintenance should only be carried out by competent staff.

� Power sources should be isolated and physically locked off (secured).

� Stored power should be released or secured to prevent accidental discharge.

Where power cannot be isolated additional precautions required are:

� Cover live parts with insulating material.

� Use additional PPE such as insulating rubber gloves.

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If dangerous moving parts have to be accessed additional precautions required are:

� Run at very slow speed rather than normal operating speed.

� Fit maintenance guards that have been made specifically to allow minimum access to required

areas only.

� Precautions should be taken to allow safe access, especially when working at height.

� Handling aids and equipment should be used to reduce manual handling risk.

9. Outline the factors to consider when selecting respiratory protective equipment (RPE) to give suitable

protection against exposure to airborne substance (8)

� Nature of the hazard (chemical properties, concentration in the air, warning properties)

� Physical form of the substance, e.g. gas, vapor or particulate (mist, dust or fume)

� Level of protection offered by the RPE.

� It can be used in firefighting or emergencies situations.

� Presence or absence of normal oxygen concentrations.

� Duration of time that it must be worn.

� Compatibility with other items of PPE that must be worn.

10. In order to minimize the risk of injury when carrying out a manual handling operation:

A) Identify types of mechanical that can be used to assist the manual handling operation. (4)

� forklift truck,

� hoist / Electric hoist

� conveyor

� crane

� mechanized robot

� Pallet Converter

� Gravity roller

B) Other than using mechanical aids, outline ways to reduce the risks that could be presented by the load.

(4)

� Train the people on Safe lifting technique

� Assign the job to individual capability

� Avoid over loading

� Reduce the distance and time

� Use Manual Handling equipments

11. Mobile Tower scaffolds should be used on stable level ground. Outline the additional factors that

should be considered for the safe use of mobile tower scaffold. (8)

� Guard-rail fitted to the work platform.

� Tower must not be overloaded.

� Wheels should be locked when the tower is in use.

� Close boarding of working platforms – minimizing gaps between scaffold boards or placing

sheeting over the boards so that material cannot fall through.

� Tower must be sited on firm, level ground.

� People and materials should not remain on the tower when it is moved.

� Care should be taken to avoid overheads when the tower is moved.

� People should not climb up the outside of the tower.

� Tower must be built by trained workers.

� Weather conditions