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1

A telecommunications worker needs to lift a 20kg manhole cover in order to repair fibre optic cables.
The working area is 1.5m below ground and 1m from the kerb of a busy road.
a) Identify four factors associated with the worker that may affect the risk of injury when removing the manhole cover. (4)
b) Outline six types of hazard associated with these activities. (6)
c) Outline possible control measure to minimise the risk to the worker and pedestrians whilst carrying out these activities. (10)

(a) Factors associated with the worker that might affect the risk of injury when removing the manhole
cover include:
- his physical strength and stature;
- his age and health status; his capability, which might be affected by an inherent disability;
- the training or lack of it that he had been given in manual handling and lifting techniques;
- and a failure by his employer to provide appropriate personal protective equipment such as gloves and safety footwear.

(b) arising from the need to lift
the heavy manhole cover;
- the possibility of falling into the open manhole;
- hazards arising frompassing traffic such as noise, fumes, and the possibility of being struck by a vehicle;
- hazards connected with working in a confined space, such as the means of access, and the possibility of flooding or lack of oxygen;
- electrical hazards from handling the fibre optic cables;
- biological hazards from contaminated water in the working area – Weil’s disease; the ever present possibility slipping /
- tripping over the manhole cover or tools left on the ground; and hazards associated with lone working.

(c) making an initial arrangement for two persons to be involved in removing the manhole cover using appropriate tools
such as T-piece keys.
- There would then be a need to provide a safe access / egress to the manhole
such as fitting dedicated rungs;
- arranging for the provision of ventilation for the manhole by mechanical means where testing has shown this to be necessary;
- the provision of a suitable temporary cover for the manhole in times of inclement weather;
- the provision and wearing of
personal protective equipment such as helmets, boots, gloves and high visibility jackets;
- ensuring that employees have adequate means of communication with a control centre such as mobile telephone or radio.
- Finally there might also be a need to arrange for the management of passing traffic and pedestrians by the provision of barriers, cones and warning lights and to ensure that the manhole cover when removed and tools in use do not cause a tripping hazard for pedestrians.

2

Outline the precautions necessary for the safe storage and handling of small containers of flammable solvents. (8)

Precautions that should be considered when storing and handling flammable solvents in small containers include:
- selecting containers that are suitable for the purpose;
- labelling the containers
clearly with information about their contents;
- marking the storage area in which they are held;
- ensuring that empty containers are tightly closed and stored outside the building or in a store constructed of fire resisting materials;
- taking measures to prevent vapour build-up by the provision of a good standard of ventilation
- prevent or reduce the impact of spillages by using non-spill caps or bundling the area where the containers are held;
- removing likely sources of ignition;
- limiting the quantities stored and the amounts in use;
- controlling the disposal of flammable waste;
- providing suitable appliances for fighting fire.

3

Outline the precautions to protect against electrical contact when:
a) Excavating near underground cables. (4)
b) Working in the vicinity of overhead power lines. (4)

(a) isolating the supply;
- identifying cable routes from plans and by the use of cable detectors;
- marking cable routes on site;
- checking for service box covers and other street furniture;
- digging with hand tools rather than using a
mechanical excavator.

(b) precautions for work near overhead power lines include:
- isolation of the supply where this
is possible following consultation with the supply provider;
- the erection of goal post barriers on either
side of the lines to define clearance distances;
- the clear marking of danger zones (e.g. with signs);
- ensuring safe access routes under the lines;
- using marshals and banks persons when there is a possibility that cranes, excavators or tipper lorries might approach overhead lines;
- restricting the use of items such as metal ladders and scaffold tubes near live lines.

4

a) Describe the differences between acute and chronic health effects. (4)
b) Identify the factors that could affect the level of harm experienced by an employee exposed to a toxic substance. (4)

(a) Acute - adverse effects appear after a single or short term exposure to the agent, and the response is invariably rapid or immediate.
In most cases, acute effects recede on cessation of exposure.
Chronic health effects, on the other hand, usually result from prolonged or repeated exposure to the agent. The response is normally gradual, often progressive and irreversible, and may go unrecognised for long periods of time.

(b)the route of entry of the toxic substance into the body and the associated mode of exposure;
- the concentration, physical state and
toxicity of the substance;
- the level, duration and frequency of the exposure;
- the effectiveness of the control measures in place;
- personal factors such as the age, gender, health status and susceptibilities of those exposed.

5

Identify the hazards a skip collector would be exposed to when moving a full skip from the ground on to the back of a skip loader vehicle. (8)

- hazards such as contact with the
vehicle mechanisms, such as the hydraulic arms and loading frame;
- becoming trapped in the chains
and skip or lifting lugs;
- contact with the moving skip;
- contact with overhead obstructions;
- uneven loading of the skip; overloading of the skip, which might lead to mechanical or structural failure;
- skip contaminants, which could include biological material, asbestos or sharps;
- trips or falls caused by the slippery surface on the flatbed of the vehicle or uneven ground conditions whether on the road or in the skip location;
- being struck by passing traffic.

6

A number of employees who are required to work with vibrating handheld tools for lengthy periods during a work shift have reported symptoms of tingling and numbness in their fingers. Further
analysis indicates that the employees concerned could be showing early symptoms of hand–arm
vibration syndrome (HAVs).
a) Describe further symptoms that might develop should the work continue. (4)
b) Outline the factors to consider when assessing the risk of HAVs developing amongst the employees. (8)
c) Outline the precautions that could be taken to minimise the risk of the employees developing the condition. (8)

(a) • blanching of the fingers;
• swollen and painful joints; and
• reduction in dexterity, strength and sensory perception

(b) factors considered include sources of vibration such as:
• vibrating, reciprocating and rotating tools and equipment;
• age of the equipment;
• number of employees using the equipment;
• manufacturer’s information.
Further consideration would then have to be given to:
• frequency, magnitude and direction of the vibration;
• duration of use;
• environmental factors such as exposure to cold weather;
• the force required to hold the equipment against the material to be processed or vice versa;
• personal factors such as pre-existing circulatory problems; and
• assessment of the current controls provided.

(c) • substituting the tools with lower vibration equipment;
• reducing exposure time by regular breaks and job rotation;
• planning maintenance programme for tools;
• introducing a defect reporting procedure;
• considering limiting work to warmer environments;
• providing appropriate Personal Protective Equipment such as gloves; and
• providing instruction and information to employees on the correct working practices.

7

A well found on a development site needs to be made safe before construction work can begin.
a) Identify the hazards that may be present in these circumstances. (4)
b) Outline the control measure that could be used in order to render the well safe. (4)

(a) falling in and/or drowning;
- confined spaces;
- hazards arising from oxygen deficiency
- toxic gases;
- possible collapse of the sides of the well.

(b) use of fences or barriers to establish an exclusion zone;
- covering the well;
- (the most effective method) draining the well and filling with hardcore or other material.

8

Question 8
a) Identify the possible indications of a dust problem at work. (4)
b) Explain how a static dust sampler is used to assess the level of airborne dust in a workplace. (4)

(a) • fine deposits on surfaces, people and products;
• visible dust particles in the air;
• plant issues such as blocked filters;
• complaints of discomfort and irritation; and
• cases of ill health reported or detected by health surveillance.

(b) • Should first be selected.
• Pre-set the flow rate on the pump.
• Weigh the filter.
• Place the sampler and pump in the designated area.
• After drawing a pre-determined volume of air through the filter, it would be sent to a
laboratory for analysis. The quantity and chemical composition of the dust would be
determined.

9

Documents have been collected into sacks and are to be individually destroyed using a document
shredder.
a) Outline the mechanical and non-mechanical hazards associated with this task. (10)
b) Outline precautions that could be taken to minimise the risk of injury during this task. (10)

(a)
Mechanical - possibility of the operators being cut by the shredder blades, being drawn into the blades and being crushed between the shredder and collection box. Non-mechanical - would include damaged or exposed electrical cables; the manual handling of sacks; the need for excessive
bending or twisting to carry out the operation; contact with hot surfaces on the shredder; noise from the machine and the presence of dust; trips and falls resulting from a poor standard of housekeeping;
and constant contact with the documents which could cause dermatitis.

(b)- provision of guarding for the shredder blades together with trip devices and reversing controls;
- the introduction of a system for the regular inspection and maintenance of the machinery;
- the introduction of a breakdown procedure involving isolation of the machine from the power supply and the allowance of sufficient time for the shredder mechanism to cool down;
- the possibility of providing an automatic
feed to the machine and if this was not possible the provision of mechanical handling aids such as trolleys or trucks;
- the provision of specific training to the employees in the operation of the shredder
and in manual handling; ensuring the workplace was provided with adequate ventilation and lighting;
- the erection of barriers or screens to reduce noise levels;
- ensuring the operators were given frequent breaks with consideration being given to job rotation;
- providing personal protective equipment
such as dust masks and gloves.

10

Identify the main hazards that may be present during the demolition of a building. (8)

- falls from a height or on the same level;
- falling debris and premature collapse;
- use of explosives; contact with and noise from equipment and heavy plant;
- dust (possibly including asbestos);
- the presence of hazardous materials from previous uses of the building;
- the presence of cellars or vaults affecting the stability of adjoining premises;
- the possible presence of services such as electricity, gas and water; hot work;
- biological hazards from the presence of stagnant water and vermin.

11

Outline the factors to consider when selecting respiratory protective equipment (RPE) that would give suitable protection against exposure to solvent vapour. (8)

- the characteristics and hazardous nature of the solvent to be used and its workplace exposure limit (WEL);
- the amount and degree of the anticipated
exposure and the intended frequency and duration of use of the equipment;
- the level of protection required with reference to the assigned protection factor (APF) given to the equipment by the
manufacturer;
- the existence of a CE approval; the type and availability of the filter used in the
equipment and the cost of replacements;
- the compatibility of the equipment with other personal protective equipment and the degree of comfort afforded to the wearer; the introduction of procedures both for initial fit testing and for subsequent inspection, maintenance and storage;
- the health of the employees who would be expected to use the equipment and the introduction of a programme of health surveillance;
- the provision of training in the use of the equipment and its limitations;
- finally the provision of adequate levels of supervision to ensure its continued use
when required.

12

Outline the factors that should be considered when providing a means of escape in a workplace so
that all employees are able to reach a place of safety in the event of a fire. (8)

- factors such as the number of employees
and their location in the premises;
- the number of exit routes required;
- the width of the exit routes dependent on the fire risk;
- the travel distances involved depending on the fire risk and the number of exits with all escape routes leading to a final exit, the door of which should open quickly and easily and preferably outwards;
- the protection of fire exit routes with fire resistant materials and the fitting of self-closing fire doors along corridors and protected routes;
- the provision of adequate signage for
and emergency lighting along exit routes;
- the introduction of procedures for disabled persons, including the provision of safe havens and fire fighting lifts;
- the location of fire fighting equipment
along exit routes;
- the need to appoint responsible persons such as fire marshals and emergency
services liaison personnel;
- the means for raising the alarm, which should have sufficient call points and be audible throughout the premises.

13

An electrically powered chemical pump, operating at 90°C, has developed a leak. Outline the control measures that should be taken for the repair of this item of machinery. (8)

The operation described would normally be one for which a permit-to-work would need to be issued.

This would ensure that control measures are taken such as isolating and locking off the electrical power to the pump;
- isolating pipelines to the pump by locking valves or inserting blanks;
- releasing stored energy by de-pressurisation and draining any chemical contained in the pump and decontaminating or neutralising it;
- allowing the pump if hot to reach room temperature;
- segregating the repair work by the provision of barriers and warning signs; providing safe access for those carrying out the repair such as scaffolding if the work had to be carried out at a height;
- using skilled and competent personnel to carry out the work and ensuring they were provided with and used personal protective equipment such as full face respirators,
- chemical suits and gauntlets;
- putting in place arrangements to deal with an emergency such as the control of spillage;
- ensuring the work area was provided with sufficient light and ventilation;
- arranging for adequate supervision and the constant presence of a stand-by person.

14

Identify possible hazards that could cause employees to be injured when walking through an external storage area of the workplace. (8)

These would include:
- the condition of the floors with the possible presence of pot holes, loose coverings, oil and water;
- the presence of obstructions in the walkways; changes in levels such as ramps, kerbs or steps;
- a failure to provide barriers or fences around pits, voids or trenches;
- the possibility of being struck by moving
vehicles because of a failure to segregate vehicles from pedestrians by the provision of suitable walkways;
- objects projecting or falling from racking;
- a lack of housekeeping;
- a poor standard of lighting; and prevailing weather conditions.

15

Outline practical measures that reduce the risk from electricity when using a portable electrical appliance. (8)

- use of undamaged and properly routed cables;
- the fitting of fuses of the correct rating;
- the use of reduced voltage by means of a 110v step down transformer centre tapped to earth;
- the use of double insulated (class II equipment) or battery operated (cordless) equipment;
- the use of the appliance in association with a residual current device protecting individuals by rapidly disconnecting the power in the event of a fault occurring; ensuring earth continuity;
- ensuring the equipment is tested frequently and records kept;
- avoiding the use of the equipment in wet weather;
- carrying out regular visual inspections and user checks.

16

In order to minimise the risk of injury when undertaking a manual handling operation:
a) identify FOUR types of mechanical aids that can be used to assist the manual handling operation.(4)
b) other than using mechanical aids, outline ways to reduce the risks that could be presented by the load. (4)

(a) mechanical aids to assist manual handling
operations such as trolleys, hoists, chutes, levers, conveyors, goods lifts, forklift trucks, wheel barrows and handling devices such as hooks or suction pads.

(b) reducing the risks that could be presented
by the load such as lightening the load by splitting it; providing handles for the load; covering
- removing sharp edges;
- making the external cover less slippery and easier to grip;
- marking the weight of the load;
- indicating the position of the centre of gravity;
- wearing gloves; and using team lifting.

17

a) Identify the possible effects on health that may be caused by working in a hot environment. (2)
b) Outline the measures that may be taken to help prevent the health effects identified in (a). (6)

(a) skin burns from radiant heat, dehydration and muscle cramps, heat cataracts and heat stress and exhaustion, tiredness and fatigue

(b) provision of screens to protect against radiant heat;
- minimising the exposure time of employees by providing regular workbreaks;
- providing and encouraging the consumption of cool refreshments;
- increasing ventilation;
- decreasing humidity by, for example, controlling the escape of steam;
- the provision of suitable clothing.
- health surveillance and the need to
allow new workers to acclimatise gradually to the environment.

18

Identify the information that should be included on a manufacturer’s safety data sheet supplied with a hazardous substance. (8)

- details of the manufacturer or supplier;
- the name of the substance;
- its physical properties and chemical composition;
- the nature of the hazard and the risks presented such as health effects and toxicological data;
- relevant standards such as workplace exposure limits and risk and safety phrases;
- precautions to be taken in its transport, handling and use, for example, the use of personal protective equipment and ventilation requirements;
- measures to be taken in an emergency such as spillage or accidental exposure
including first aid treatment
- fire fighting measures;
- the requirements for safe disposal.