IGC2 – Control of international workplace hazards

ELEMENT 1

1. List EIGHT design features and/or safe practices indented to reduce the risk of accidents on staircases used as internal pedestrian routes with work premises.

This question calls for practical suggestions on ways of preventing accidents such as slips, trips and falls on staircases. Matters that should spring to mind almost immediately include:

The removal of obstructions. The provision of non-slip surfaces, together with reflective edging. Adequate lighting and effective maintenance.

Important design features of a staircase (which are to large extend defined by building standards) are:

Its width. The provision of handrails. The dimensions of treads and risers. The provision of landings.

Better answers to this question should also refer to the need to make special provision for disabled persons and also to the possibility of using a lift as an alternative, in particular to avoid the need to carry large or heavy items up or down stairs. Site rules should address such issues as well as defining appropriate footwear.

2. Outline the precautions that might be needed to ensure the safety of pedestrians in vehicle maneuvering areas.

Answers should generally include:

References to segregated systems for vehicular and pedestrian traffic. Appropriate road markings. Maintaining good visibility(mirrors, transparent doors, provision of lighting, etc) Audible warnings on vehicles.

Other relevant measures that should be mentioned include:

The drawing up and enforcement of site rules. The provision of refuges. The wearing of high-visibility clothing. A good standard of house keeping.

Training for, and supervision of, all concerned.

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

Present a hierarchical range, from avoiding the need for vehicles to reverse (one –way and ‘drive-through’ systems, turning circles, etc) through the separation of vehicles and pedestrians (barriers, signs, etc) and aspects of vehicle and workplace design (audible alarms, mirrors on vehicles and at blind corners, refuges, lighting, etc) to procedural measures (use of banks men, site rules, driver training, etc).

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

(b) Outline how slip and trip hazards in the workplace might be controlled.

There are many reasons why people slip or trip, including the floor being poorly maintained, changes in level (with ramps, slopes or kerbs), slippery surfaces caused by oil, water or ice, inappropriate footwear, and general obstructions in walkways such as trailing cables, pipes and air hoses. Some candidates struggled to find a full range of hazards for part (a) and sometimes gave examples that were very similar in nature. Those who, for example merely gave four different types of obstruction in a walkway had only addressed one type of hazard, which reduced the number of marks that could be awarded. In answering part (b), candidates should have outlined control measures such as highlighting changes in level with hazard warning strips, providing good lighting, introducing procedures for reporting defects and for spillages, gritting oily and icy surfaces, using non slip flooring, and ensuring high standards to keep floors free of obstruction. Many answers were restricted to housekeeping issues.

ELEMENT 2

1. Identify EIGHT rules to follow when a fork-lift truck is left unattended during a driver’s work break.

Examiners expected candidates to identify rules such as the return of the fork-lift truck to a designated area on firm level ground with the mast tilted forward and the forks resting on the floor; the isolation of the power with the ignition key removed and returned to a responsible person; and the need to park the truck away from other vehicles and in a position that did not block emergency exits.

Most candidates achieved a good / reasonable mark for this question even though on occasions Examiners were required to interpret some answers where forks were referred to as “spikes” or “bars” and the mast as a “boom” or “stack:.

2. Outline the precautions to be taken when using a mobile elevating work platform (MEWP) to reach a high point such as a streetlight.

Candidates should outline precautions such as:

The need to inspect the equipment before use and to ensure it is in a good state or repair. Using only competent workers. Using outriggers and brakes. Erecting warning signs and barriers to avoid collisions. Ensuring the platform is not overloaded. Avoiding overhead obstructions. Wearing a harness.

3. (a) List FOUR specific types of injury that may be caused by the incorrect manual handling of loads.

(b) Outline the factors in relation to the load that will affect the risk of injury.

Part (a) of the question asked for a list of specific injuries that might be caused by the incorrect manual handling of loads. These would include spinal disc compression or slipped discs, torn ligaments or strained or sprained tendons, hernias, dislocations and fractures, muscular strains, cuts and abrasions, and crushing and impact injuries. While there were some good answers to this part of the question, too many candidates referred in vague and general terms to back, muscular and hand injuries when a more specific answer was required.

Part (b) tested candidates’ knowledge of how the nature of a loan can affect the risk of injury during manual handling activities. They should have identified matters such as the size and weight of the load, the possibility that the contents might move and the load become unbalance, the weight distribution (the centre of gravity not being in the centre of the load), difficulty in securing a firm grasp of the load, and the presence of sharp edges or very hot or cold surfaces. Again, better candidates were able to provide a focused answer with sufficient detail to demonstrate a clear understanding of the issues. Other answers, however, were extremely brief (sometimes no more that four words) and a few identified controls instead of risk factors.

ELEMENT 3

1. Outline four main types of guards and safeguarding devices that may be used to minimize the risk of contact with dangerous parts of machinery

Moving machine parts have the potential to cause severe workplace injuries, safeguards are essential for protecting workers from these preventable injuries. Some of the safeguarding that may be used on the machines may include: Fixed Guards – which forms the permanent parts of the machines, these types of guards is usually preferable to all other types because of its relative simplicity and performance: Adjustable Guards – These guards can be adjusted according to

the work or workplace. It is important that such guards are properly adjusted and maintained for them to be effective: Automatic Guards – These guards are self adjusting and can be automatically moved into position as the machine or cycle starts: Self adjusting guards – These types automatically opens and closes as the work piece is put in and pulled out: Interlock guards – When this type of guard is opened or removed, the tripping mechanism or power automatically shuts off or disengages, the moving parts of the machines are stopped and the machine cannot cycle or be started until the guards are back in place

The different types of safe guarding devices that may be used may include the following: Presence sensing devices – The photo electric presence sensing device uses a system of light sources and controls which can interrupt the machines operating cycle: Pullback devices – Pull back device utilizes a series of cables attached to the operators hands, wrists and arms. This type of device is primarily used on machines with stroking actions. Safety trip controls: Safety trip controls provide a quick means for deactivating the machine in an emergency situation: Two hand controls – Concurrent use of two hands on separate controls prevents hands from being in danger area when the machine cycles starts. The two hand control requires constant, concurrent pressure by the operator to activate the machine.

2. Identify eight types of non – mechanical hazards associated with the use of machinery

Machinery may also present other hazards and suitable measures need to be taken to prevent the injury. Some of the non – mechanical hazards are:

Electrocution to the workers can happen if they come in contact with the naked wires or other electrical parts / connections of the machine

Burns result on contact with the hot parts of the machine Dust and fumes from the point of operation or from the exhaust systems Fire / Explosion due to leakages of fuel Noise and vibration Radiation from the activities done on the machine Flying chips and sparks from the point of operation Hazardous chemicals Manual handling

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

(b) For the hazards identified above, outline the control measures that can be used to reduce the risk (May, 2010)

(a) Some of the hazards associated with the trimmer while working on it are:

Entanglement with the rotating parts of the machinery Trapping of the body parts or clothes inside the moving parts Electrocution Noise and Vibration Ejection of materials while working

Manual handling Chemical

(b) To protect the workers from the above mentioned hazards, the following control measures should be taken into consideration. The rotating parts or other moving parts of the machinery should be protected by means of adequate guards or body coverings. Provide workers with ear plugs / muffs to protect them against the noise generated by the mixer. When removing the drum for storage or transportation make sure the machine is properly switched off and unplugged. Avoid putting anything like hand, shovel or anything other than the mix into the drum while it is rotating.

4) A public services worker uses a petrol-driven strimmer to maintain roadside grass verges.

(i) Describe the possible hazards faced by the worker in carrying out his task. (10)

(ii) List FIVE items of personal protective equipment that should be provided to, and used by the worker.

(iii)Outline measures other than the use of personal protective equipment that might be necessary to ensure the health and safety of the worker.

This question is designed to test the ability of candidates to apply basic principles of health and safety to a practical situation. Part (i) requires candidates to describe the possible hazards faced by workers using a petrol-driven strimmer on grass verges on the roadside. These would include:

Contact with the moving parts of the strimmer. The possibility of being struck by flying stones or other material. 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.

Candidates who provide only a bare list of hazards without further amplification should not expect to be awarded all the marks available since the question clearly asks for a description. For instance, identification of extreme weather conditions as a hazard requires some mention of ultra-violet radiation and the effect on the skin. Other hazards are perhaps a little more obvious and require rather less by way of description. Nevertheless, some indication should be provided of how each particular hazard presents itself in the situation given. Part (ii), on the other hand, does require candidates to provide a list. This should include reference to:

Ear defenders. Eye protection. Respiratory protection (dust mask). Gloves. Safety footwear.

Gaiters. High visibility clothing that also afforded protection against the weather.

For part (iii) outline measures such as:

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 is undoubtedly a useful starting point, but the assessment alone without the further possible action that should follow is not sufficient to ensure the health and safety of workers.

5) Outline the sources and possible effects of FOUR non-mechanical hazards commonly encountered in a woodworking shop.

The key expression in this question is ‘non –mechanical’. Candidates should be able to outline hazards such as:

Dust from sawing and sanding operation (leading to lung disorders and possible Cancers). Chemical hazards from varnishes, glues etc (leading to a range of ill-health effects). Noise from machinery (causing noise-induced hearing loss and other auditory and non-auditory effects). Sharps and splinters (causing eye injuries, cuts and infections). Manual handling hazards (resulting in musculoskeletal disorders). Electricity (causing shock, burns and fire).

ELEMENT 4

1. (a) Identify the effects on the human body from a severe electric shock

(b) Outline how earthing can reduce the risk of receiving an electric shock.

(c) Identify FOUR factors that could affect the severity of injury resulting from contact with electricity

(a) Flow of electric current through human body results in electric shock, but with

increased current it can have other effects on the human body such as; Muscle control will be affected

Breathing difficulties Internal / External burns Un co ordinate series of contraction of heart muscles causing irregular heart beat

which can result in even death Secondary Hazards – Person can fall from height and suffer injury due to electric

shock, Health hazards due to release of toxic gas and creation of UV rays.

(c) Severity of injury on human body will depend upon on the severity of shock, so the

factors which can affect the severity of injury will include.

Amount of current flowing through the human body

Path through which the current passes through the human body

Duration of contact with electricity

Contact area of the human body – Higher the contact area higher will be the

amount of current flow

Resistance or the conductivity of the human body

2. Outline precautions that should be taken to reduce the risk of harm from electrical equipment in a workplace.

Hazards associated with the use of electrical equipments can be controlled through their proper use and care. It is necessary to establish safe work practices in compliances with safety rules for the use electrical equipments at the workplace. To avoid the risk of electrocution the following should be taken into consideration; Electrical supply to the equipment should be taken through proper fuse, power supply to the electrical tools should be taken through ELCB / GFCI, plug casing should be free of damages, electrical equipments should be provided with proper grounding. The use of two layer of insulating materials around the electrical equipment (Double Insulation) avoids the need for an earth conductor as there is no exposed conductor which may become live. Shut off the electrical supply to the equipment when not in use and preventing the system from being mistakenly operated. Do not use the equipment in damp or wet location unless they are approved for that purpose. Use gloves and appropriate safety foot wear when using electrical tools or equipments.

3. Outline a range of checks that should be made to ensure electrical safety in an office environment.Answers can include reference to visual inspections for damage to cables, plugs and sockets, the need to ensure that all fuses are of the correct rating, and checking that equipment is sited such that outlets are not overloaded and cables are not in vulnerable positions. The equipment itself should be checked to ensure suitability and conformity with recognized standards (e.g. CE

Marking) for Europe and a specific testing procedure for portable appliances should be in place, as well as a procedure for reporting defects or damage.

2. In relation to the use of electrical cables and plugs in the workplace:

(i) Identify FOUR examples of faults and bad practices that could contribute to electrical accidents.

(ii) Outline the corresponding precautions that should be take for EACH of the Examples identified in (i).

For part (i), examples include:

Failure to select the right equipment for the environment (e g armored or heat resistant cable might be required in arduous conditions). Incorrect rating of fuses. Ineffective or discontinuous earthing. Overloading of socket outlets. Cables unnecessarily long (or short). The use of coiled extension leads. Poorly wired plugs (e g wires under tension or outer protective sheath not clamped). The use of defective cables and plugs.

For part (ii) an outline of relevant precautions for the examples identified are required:

Earthing Calculate correct rating for a fuse. Residual current device (RCD). Reduce voltage. Battery powered. Double insulation.

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

(i) ‘Isolation’. (2) (ii) ‘earthing’. (2) (iii) ‘reduced low voltage’ (2) (iv) ‘over current protection’ (2)

The question aimed to test candidates’ knowledge of some key electrical terms. ‘Isolation’ refers to shutting off the electrical supply to an item of equipment or part of an electrical system and preventing inadvertent reconnection in order, for instance, to carry out maintenance work. ‘Earthing’ on the other had, is a means whereby electrical equipment and conductive items are connected to earth by a cable or metal pipe work such that the route to earth provides the path of least resistance to a current flowing under fault conditions. ‘Reduced low voltage’, commonly

used on construction sites, involves the reduction of local supply voltage by a transformer to a lower, safer voltage – typically 110 or 55 volts; while ‘over current protection’ is a method of preventing the flow of excess current by cutting the supply under fault conditions by means of a fuse or circuit breaker.

ELEMENT 5

1. (a) Identify the principles of the ‘fire triangle’/ Identify key components of ‘fire triangle’

(b) Identify three methods of heat transfer and state how each contributes to the spread of fire. (June, 2010)

(a) There are three factors required to support combustion and these factors are:

Fuel: Which may be in the form of solid, liquid, gas or metal Oxygen: Which may be present in air Heat: This forms the source of ignition.

(b) Transfer of heat can happen by any of the following methods:

Conduction – The movement of heat through a material. Metals are good conductors of heat so the flammable materials in contact with it can catch fire.

Radiation – Transfer of heat through air. The solids or liquids in contact with the air will get heated due to this.

Convection – The movement of hotter gases up through the air. The heated air can pass through the gaps and can cause fire to start elsewhere

Direct contact – Combustible materials in contact with the naked flame.

For part (b) candidates could have chosen three methods of heat transfer from the following: conduction (where, for example, heat can travel through metal beams between separate compartments); radiation (where heat is radiated through the air and affects material at a distance); convection (the upward transfer o heat by gases such as air) and contact or direct burning (where a heat source comes into direct contact with combustible material causing ignition).

2. Identify common causes of fires in the workplace. (April, 2010)

Some of the common causes of fires in the workplaces are:

Placing flammable materials / articles close to the heat Faulty appliances and leads Faulty fuel supplies Careless handling of flammable materials / Unsafe storage of flammable materials Open flames e.g. cutting and welding torches

Electrical faults e.g. poor connections, damaged insulations, overloaded circuits Heat generated due to friction / Static electricity Spontaneous ignition Combustion sparks

3. Identify sources of ignition that may cause a fire to occur, AND give a typical workplace example of each. (May, 2010)

The sources of fire in the workplace arise from either inadequately controlled ignition sources or combustible materials

Electrical faults e.g. poor connections, damaged insulations, overloaded circuits etc. Friction e.g. hot bearings Open flames e.g. welding & cutting torches Spontaneous ignition e.g. coal stacks, oily wastes etc. Hot surfaces e.g. hot ducts of flues, electrical lamps etc. Combustion sparks e.g. rubbish burning, furnaces etc. Smoking & Matches Unsafe storage of materials Static electricity

4. In relation to the classification of fires give an example of a material (fuel) that falls within each the classes A, B, C and D. (April, 2010)

Class A Fires: are those that occur in materials such as wood, paper, rags and rubbish

Class B Fires: are those that occur in the vapour – air mixture over the surface of flammable liquids such as gasoline, oil, grease, paints &thinnersClass C Fires: fires involving flammable gases such as propane, butane or natural gases

Class D Fires: fires that occur in combustible metals such as magnesium, titanium and sodium

5. Outline methods of fire extinction in the workplace. (February, 2010)

The basic principles of fire extinction are 1) Cooling 2) Starvation and 3) Smothering Reducing the temperature of the heat by using any source of medium is called as cooling. Removing or not feeding further fuel to fire is called Starvation, e.g. removing flammable materials around the fire while extinguishment by separation of oxygen from fire is called Smothering, e.g. blanketing diesel fire with foam

6. Outline the factors to consider when carrying out fire risk assessment of a workplace (June, 2010)

The factors that need to be considered when carrying out fire risk assessment are; Construction and use of building – which may include the type of materials, used for construction, fire resistant capacities of the material, exits for occupants to escape etc.; Presence and the amount of flammable materials inside the building; Source of ignition inside the building; Work activities generating heat; Methods of control; Means of fire detection – The presence of fire alarm, sprinklers etc. inside the building; Means of raising alarm; Means of fighting fire and maintenance of equipment – Whether the extinguishers, fire hydrants etc. provided in the building are sufficient or not; Number of persons specifically at risk – Who and how many persons are at special risk like pregnant women, disable person etc.

7. List EIGHT ways of reducing the risk of a fire starting in a workplace.

This question requires candidates to provide a simple list. Candidates can choose from a list including:

The control of smoking and smoking materials. Good housekeeping to prevent the accumulation of waste paper and other combustible materials. Regular lubrication of machinery. Frequent inspection of electrical equipment for damage. Ensuring ventilation outlets on equipment are not obstructed. Controlling hot work. The provision of proper storage facilities for flammable liquids and the segregation of incompatible chemicals.

8. (a)Explain, using a suitable sketch the significance of the ‘fire triangle’.

(b)Identify TWO methods of heat transfer and explain how EACH method can Contribute to the spread of fire in work premises.

Part (a) of this question required candidates to explain, with a clearly labeled diagram, that each side of the fire triangle represents one of the three elements – namely, fuel, oxygen and a source of ignition – that must be present for combustion to occur. This part of the question was generally well answered.

Whilst many candidates where able to identify two methods of heat transfer, explanations of how each of the two examples quoted spread fire within a work premise varied considerably in quality especially amongst those candidates who had chosen direct burning and conduction. Again, some candidates did not read the question and wasted valuable time by outlining four methods of heat transfer. It is important that candidates read the question properly to prevent them from answering previously set questions.

ELEMENT 6

1. (a) Identify three forms of biological agents.

(b) Identify possible routes of entry of biological organisms into the body.

(c) Outline control measures that could be used to reduce the risk of infection from biological organisms.

For part (b), candidates can choose from a list including:

Inhalation – Biological agents can enter the body through inhalation and reach lungs and blood

Injection - A forceful entry through the skin as a result of an injury can carry the agents through the skin barrier

Absorption - Biological agents can also enter through the skin, cuts or abrasion

Exchange of body fluids and through the ingestion of the agents through mouth.

In answering part (b), candidates should bring to mind hospital or laboratory situations. This should include an outline of measures such as:

The risk of infection from the biological organisms can be reduced by the following methods, Cleaning / Disinfecting – By keeping the work areas clean and washing hands or body with soaps or any other disinfection liquids; By treating the water being used for healthy conditions; By washing the hands and body in periodic time intervals: Medicines can be consumed so as to develop resistance against specific infections / agents; Using PPEs such as aprons, gloves, masks etc. while working with biological agents; Workers should be provided with specialized trainings with respect to safe handling and disposal of biological agents / wastes

2. A worker is engaged in general cleaning activities in a large veterinary practice. (a) Identify FOUR specific types of hazard that the cleaner might face when

undertaking the cleaning. (b) Outline the precautions that could to taken to minimize the risk of harm from these hazards.

Hazards that specifically associated to cleaners are:

Cleaning fluids. Manual handling. Slips/trips/falls. Presence of sharp objects / projections can cause penetration hazards. Those associated with the working environment, such as biological hazards, contact

with animals and those arising from the use of specialized equipment.

In answering part (ii), Examiners are looking to candidates to outline precautions such as:

The provision and use of personal protective equipment (including overalls and gloves). The introduction of a procedure for the handling and disposal of sharps. The need for animals to be kept in secure enclosures. The possible need for immunization against diseases known to be transmitted by animals. Highlighting that the worker would need specific training in the precautions outlined will gain an additional mark.

3. A company produces a range of solid and liquid wastes, both hazardous and non - hazardous. Outline the arrangements that should be in place to ensure the safe storage of the wastes prior to their collection and disposal. (8)

In answering this question, candidates can refer to arrangements such as:

The completion of risk assessments that address the nature, properties and quantities of the wastes likely to be stored. Minimizing the quantities stored by organizing regular collections. Ensuring the separation of incompatible wastes. Providing appropriate means for containing the wastes in secure storage facilities (e g protected against unauthorized persons, weather, vehicles, etc). Installing and maintaining fire protection and fire-fighting systems in the case of Flammable or combustible wastes. Installing bunds and drawing up procedures to deal with slippages that might preset environmental risks. Providing safe means of transport and access to the storage site. Ensuring that wastes are accurately identified and that warning signs are in place where appropriate. Training employees in the precautions to be taken. Ensuring that they are provided with, and use, appropriate personal protective equipment, such as gloves, overalls and eye protection.

4. Identify the information’s that should be included on a manufactures safety data sheet supplied with a hazardous substance.

Material safety data sheet describes the hazards of the material and provides instructions on how the materials can be safely handled, used and stored.

The informations generally found the safety data sheet include the following:

Information regarding the chemical which may include identification of the substances / preparation, details regarding the manufacturer or the supplier, composition / inormations on the ingredients, physical and chemical properties of the chemical, stability and reactivity, toxicology informations, ecological informations

Hazards – hazard identification and health effects Precautionary Measures – First aid measures, fire fighting measures, accidental release

measures, handling and storage, exposure controls, personal protective equipments Environmental Issues – Environmental / disposal considerations Other types of informations – Regulatory information, other relevant informations

5. (a) Give the meaning of:

(*) ‘Hazardous waste’ (*) ‘Non- hazardous waste

(c) Outline the key design features of a permanent spill protected / bunded area in order to protect against accidental releases and pollution.

(a) (*) Hazardous wastes are those which is harmful and / or dangerous to health and the environment which on disposal get decomposed and results in the formation of harmful products.

(*) Non hazardous wastes are those which is not harmful either to the health or the environment and does not decompose and result in the formation of harmful products.

(b) Bunds around the tankages are provided to protect against the accidental releases and the

pollution cause by the chemicals or the flammables. A good structured bund should be always located on a stable ground and at suitable distance from the water courses without connections either to the drain or sewer. It should be provided with a concrete slab base and walls with the surface of both being impervious. There should be adequate space between the containers and the bund walls and the bunded area should have a capacity of 110% of the total capacity of the containers. The bunded area should have proper protection against the temperature and the climatic conditions (weather proof) and also against the damage from the possibility them being struck by passing plants and vehicles. Bunds should be provided with proper provisions for emptying the spills in case of accidental releases and with proper monitoring systems.

6. Ammonia has been released into the atmosphere of a workplace.

(a) Outline the typical health effects resulting from exposure to ammonia(b) Give the meaning of the term ‘acute heath effects’(c) Identify suitable air monitoring methods for ammonia.

(a) Typical health effects resulting from exposure to ammonia may include irritation and possibly burning of the respiratory system, pulmonary oedema, coughing and sneezing, eye irritation together with running eyes and nose, irritation and burning to the skin.

(b) Acute health effects means effects resulting from a single short term exposure producing an immediate effect which is usually reversible e.g. Alcohol effecting the nervous system.

(c) Presence of ammonia in the atmosphere can be easily detected by anyone of the following air monitoring methods:

Stain tube detectors – Stain tube detectors provide a very convenient method of analyzing ammonia contamination of the workplace air.

Passive sampling Active sampling Electrochemical detection device such as pulsed amplified detectors

7. (a) Identify two types of asbestos to which workers in the construction industry may be exposed

(b) Give examples of where workers might find asbestos while undertaking maintenance or refurbishment work on a building

(a) Some of the types of asbestos to which workers may be exposed may include:

Crocidolite or Blue asbestos Chrystolite or White asbestos Amosite or Brown asbestos

(b) Examples of where asbestos is likely to be encountered during renovation work of a building may include; pipe lagging, asbestos cement products such as roofing sheets, loose asbestos packing used as fire breaks in the ceilings voids, sprayed asbestos coatings on steel members to provide an element of fire resistance, asbestos wool used as wall insulations, asbestos rope, gasket on boilers and coolers, certain textured coatings or decorative plasters.

8. The construction industry has a high incidence of contact dermatitis.

(a) Identify four substances used in construction that could cause contact dermatitis.

(b) Outline control measures that could be used to reduce the risk of contact dermatitis.

(a) Substances used in the construction industry that could cause contact dermatitis may include:

Degreasers, descalers and detergents Epoxy resins and hardeners Sealants such as acrylic silicone Bitumen, asphalt and tar Solvents used in connection with paints, glues and other surface coatings Cement, lime and insulation materials such as mineral wool Petrol, diesel, oil and greases.

5. For each of the following agents, outline the principal health and safety effects AND identify a typical workplace situation in which a person might be exposed:

(i) Isocyanates (2)

(ii) Asbestos (2)

(iii) Leptospira bacteria (2)

(iv) Lead (2)

Iscoyanates are a respiratory sensitizer and may also cause dermatitis. Persons carrying out work involving the use of isocyanates based printing inks, adhesives or paints would be at risk.

Exposure to asbestos may cause asbestosis, lung cancer or mesothelioma (a rare cancer that is associated almost exclusively with asbestos). Carrying out maintenance work on, or the demolition of, a building where asbestos is contained in the fabric of the structure could lead to the inhalation of airborne fibres.

An infection caused by exposure to the leptospira bacterium is called leptospirosis, with symptoms that resemble influenza (fever, chills, muscular aches and pains, etc). In rare cases, a severe form of the condition known as Weil’s disease can develop and this is characterized by symptoms that include bruising of the skin, anemia, sore eyes, nose bleeds and jaundice. Serious damage to internal organs can result, which often proves fatal. The bacterium is carried by animals, particularly rats and cattle, and exposure to the urine of infected animals can put people such as sewer workers, farm workers and vets at particular risk. While there were some good accounts given for this part of the question, Examiners were disturbed to find that many candidates confused ‘leptospira’ with ‘legionella’.

The health effects of exposure to lead are many and varied but principally include anemia, fertility problems and damage to the kidneys, the nervous and muscular systems and, particularly in children, the brain. Signs and symptoms of lead poisoning include irritability, lethargy, memory and concentration problems, muscle and joint pain, ‘wrist drop’ and a blue line of the gums. Those engaged in any activity that involves lead and produces fume, vapor or

dust (such as in battery manufacture, lead crystal glass making or the removal of lead paint) are at risk.

ELEMENT 7

1. Outline the factors that may lead to unacceptable levels of occupational stress amongst workers. (April, 2010)

Stress is the adverse reaction people to excessive pressures or other types of demand placed on them. It arises when they feel that they can’t cope. Occupational stress can rise among the workers due to the following reasons.1) The culture of the workplace including, whether or not there is a blame culture or working excessive hours. 2) The demands of the job – Whether the work is boring or repetitive type, the amount of training required and the amount of the work 3) The amount of control the worker has over their work 4) Relationships among the workers can give rise to stress especially when the relationship are poor or involve bullying or harassment 5) Changes and fears about the job security can lead to stress 6) Confusion about the employees role and what their objectives are 7) Lack of support from the management can increase the employees stress level. 8) Workplace environmental factors like inadequate lighting, cramped/ dirty or untidy conditions, poor layout, inadequate ventilation, presence of noise and vibrations etc.

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

(b) Identify the features of a chair to ensure it is suitable for use at DSE work station (October, 2010)

(a) Display screen equipments are sometimes referred to as Visual display units or computer work stations. The health hazards associated with the use of DSE may include the following:Musculoskeletal Disorders (WRULD) – The conditions affecting the arm, hands and shoulder areas linked with the work activities are described as work related upper limb disorders: Eye problems – Working long hours with DSE can give rise to burning sensations in the eyes, twitching of the eye muscles, headaches etc. Fatigue and Stress – Workers can suffer stress symptoms and fatigue due to the requirement for high speed working, lack of social interactions and lack of breaks. Radiation – Small amount of radiations being generated by the DSE causes tiredness among the workers when they continuously work for a long duration

(b) The chairs used for the DSE workstation should have the following features:

The chairs must be of swivel type and should have five or more castors The height of the chair seat should be adjustable The height and rake of the back seat should also be adjustable

If the chairs has arms , they should be either adjustable or in such a position as to not restrict the movement

The chair must allow the user to obtain the recommended ergonomically correct seating posture

3. (a) Identify FOUR types of ionizing radiation

(b) Outline the main principles of control for ionizing radiation (June, 2010)

(a) The four different type of ionizing radiations are:

Alpha Beta Gamma X-Rays

(c) By reducing the time of exposure to the ionizing radiation, maintaining a safe distance between the source of radiation and the workers, providing barriers such as lead, concrete or water will give good protection from penetrating radiations such as gamma rays. Workers should be given specialized training with respect to the hazards and preventive measures of radiation and all the works involving radiation should be carried out under strict supervision. The leftover radiation materials should be disposed off in a responsible manner. Proper monitoring of the exposed personals and also the environment should be carried out to ensure that the emitted radiations are within the safe limits.

4. (a) Identify two types of non ionizing radiations and give an occupational source of each.

(b) Outline the health effects associated with exposure to non ionizing radiations (June, 2010)

(a) The two types of non ionizing radiations can be selected from the following list of radiations:

Ultra violet rays – UV rays: Ultra violet rays can be risen from welding operations or excessive exposure to sun

Infra red rays – IR rays: rays emitted during the gas cutting operations Lasers – lasers shall be emitted from the laser equipments Microwave – rays generated from the microwaves, radar and telecommunication

equipments

(b) Non ionizing radiations can have bad effects on the health. Exposure of the eyes to the ultra violet radiations can damage the cornea and produce pain and symptoms similar to that of sand in the eye. The effects on the skin ranges from redness, burning, accelerated ageing to various types of skin cancer. Infrared rays can cause cataract in the eyes .High power lasers can cause serious damage to the eyes as well as producing skin burns. Short term adverse effect of

electromagnetic rays may include electric burns and shock. Chronic exposure to UV rays can accelerate ageing and increase the risk of skin cancer.

5. A noise survey has been conducted in a factory which has resulted in the need for provision of hearing protection

Outline the advantages and disadvantages of:

(a) Ear muffs (b) Ear plugs (June, 2010)

(a) Advantages of ear muffs are; gives a complete protection to the ears and a good reduction of all sound frequencies, designed in such a way that one size fits for most head sizes, easily seen at a distance to assist in the monitoring of their use, less attenuation variability among the users, they can be integrated with other personal protective equipment such as a hard hat, they are reusable and have a low risk of infection

Disadvantages of ear muffs are; inconvenient to use with other personal protective equipments and their reliability might be affected by the presence of long hairs, glasses or ear rings, uncomfortable to use in hot and humid work areas, inconvenient to use in confined work areas, less portable and heavier when compared to ear plugs

(b) Advantages of plugs are; small and easily carried, convenient to use with other personal protective equipments, more comfortable for long term wear in hot, humid work areas, confined for use in confined work areas. Ear plugs are available in a range of designs and types that are disposable and thus do not need to be stored after use.

Disadvantages of ear plugs are; requires more time to fit, more difficult to insert and remove, require good hygiene practices, may irritate the ear canal, difficult to see and monitor the usage, their effectiveness decrease with usage.

6. Identify four types of engineering control that may be used to reduce noise in the workplace and give a practical example of each.

7. (a) Give the meaning of the term ‘ergonomics’ (b) Identify the possible health effects that may be caused by the poor ergonomic design of display screen equipment work stations.

(c) Identify the factors to be considered in an ergonomic assessment of display screen equipment workstation. (December, 2009)

(a) Ergonomics is a science concerned with the fit between people and their work. It puts people first taking account of their capabilities and limitations.

(b) Health effects that may be caused by the poor ergonomic design of display screen equipment work stations are:

Musculoskeletal Disorder (WRULD) – There are a range of conditions of the arm, hands and shoulder area linked to work activities which are described as work related upper limb disorders.

Eye Problems – Working long hours with DSE can give rise to burning sensation in the eyes, twitching of the eye muscles, headaches etc.

Fatigue and Stress – DSE workers can suffer stress symptoms and fatigue due to the requirement for high speed working, lack of social interactions and lack of breaks

Radiation – DSE equipment produces a certain type of radiation which have a bad impact on the huma body.

8. (a) Describe the possible effects on hearing from exposure to noise

(b) Outline the factors that are likely to affect the performance of personal hearing protection

9. Outline the prevention strategies an organization could consider to reduce the risk of violence towards workers

Violence at work has been defined as any incident in which a person is abused, threatened or assaulted in circumstances relating to their work. Violence at work can be considered into two areas 1) Internal violence and 2) External violence. Organization should consider prevention strategies to workers who are potentially exposed to violence from internal or external factors.

10. (a) Identify four health effects of working outside in extreme heat created by the sun

(b) Outline the control measures that could be used to reduce the effects of the sun on construction workers (March, 2010)

(a) Working on the hot and humid climatic conditions usually has large impacts on the health of the workers. Some of the effects of the temperature on the human body are listed below:

Sun Burns – Too much of exposure to sun or working in humid conditions can cause reddening of the skin along with painful / blistering peeling of the skin

Heat Exhaustion – Working in hot or humid climatic conditions may cause fluid loss in the form of sweating which also causes loss of salt from the body. Inadequate water intake under these circumstances causes body’s cooling system to break down

Heat Rashes – Exposure to humid conditions can cause red bumpy rash with severe itching on the skin

Fainting – Fluid loss and inadequate intake of water can cause dehydration which can result in fainting.

Heat Stroke – When the human body has used up all its water and salt reserves it will stop sweating which can result in stroke.

(b) Remove or reduce the source of heat where ever possible, control the temperature using engineering controls e.g. change the processes, use fans or air conditioning, use physical barriers that reduce exposure to radiant heat. Providing periodic breaks and rest facilities in cooler conditions and by circulating cool drinking water for the workers prevents them from dehydration. Allow the workers to work in shifts so that they may not be fully exposed to the humid conditions. Provide suitable personal protective equipments to the workers. Prevent employees who are more susceptible to heat stress either because of an illness or medications that may encourage the early onset of heat stress.

11. In relation to the ill-health effects from the use of vibrating hand-held tools:

(i) Identify the typical symptoms that might be show by affected individuals.

(ii)Outline the control measures that may be used to minimize the risk of such effects.

In answering part (i) of the question, Examiners expected candidates to identify symptoms such as numbness and blanching of the fingers and swollen and painful joints in addition to a reduction in dexterity, strength and sensory perception. Many candidates concentrated on diseases and not symptoms and there appeared to be confusion between noise and vibration which was demonstrated in part by references to deafness and ear/eye damage.

For part (ii), candidates should have outlined a hierarchy of control measures such as elimination by mechanization or automation; substituting the tools with lower vibration producing equipment; reducing the time of vibration exposure to the operatives; introducing a planned maintenance programme for the tools and providing appropriate personal protective equipment such as gloves to keep hands warm. Few candidates were able to produce this hierarchy of control measures with most referring inaccurately to the use of personal protective equipment to protect against vibration.

12. (a) For EACH of the following types of non-ionizing radiation, identify a source and state the possible ill-health effects on exposed individuals:

(i) Infrared radiation (ii) Ultraviolet radiation.

(b) Identify the general methods for protecting people against exposure to non- ionizing radiation.

In answering part (a) typical sources: Infrared radiation – fire or furnaces. UV light – welding operation.

Health effects caused are:

Burns to the skin and eye damage) common to both types of radiation). Effects of the sun (sunburn and skin cancers).

For part (b), these include:

Shielding. Increasing the distance between source and person. Reducing the duration of exposure. Appropriate personal protective equipment (such as clothing and eye protection) The use of barrier creams.

13. An office building is about to be occupied by new owners.

(i) Outline the factors that should be considered by the new owners when assessing the suitability of lighting within the building.

(ii) Describe FOUR effects on health and safety that might result from inadequate lighting.

(iii) Outline the welfare facilities that should be provided in the building.

Part (i) of this question requires an outline of the factors to be considered when assessing the suitability of lighting within an office building. With eight marks available, this should have given a clear indication to candidates that reasonable outlines of a range of relevant factors are needed. Examiners expect candidates to outline factors such as:

The type of work to be undertaken. The type of equipment to be used. The possibility of glare at work stations and on VDU screens. The availability of natural light during both summer and winter. The type of artificial light provided. The requirement for local lighting for specific tasks. The availability of emergency lighting. The number of lighting units provided in relation both to the floor area and to the amount of light emitted from each one.

Also important is the possibility of shadows being cast and contrasts in lighting levels between one area and another.

In part (ii) there are marks to be gained for descriptions of the possible effects on health from inadequate lighting, such as eyestrain, headaches and increased levels of stress. Additionally, candidates are expected to refer to other relevant health and safety effects, such as trips and falls, and the possibility of errors in performing tasks that might then put others at risk.

A comprehensive answer to part (iii) of the question includes reference to:

The provision of sanitary conveniences (adequate in number, separate male and female etc). Suitable and sufficient washing facilities. A supply of drinking water, eating and rest areas. Accommodation for clothing. First aid facilities. Protection for non smokers against passing smoking. Rest facilities for expectant and nursing mothers.

14. (a) Explain the following terms in relation to noise exposure at work. (i) ‘noise-induced hearing loss’ (ii) ‘tinnitus’ (b) Identify FOUR limitations of personal hearing protection as a means of protecting against the effects of noise.

For part (a), a general understanding of the effects of noise on hearing is required. Noise-induced hearing loss is normally caused by prolonged exposure to high noise levels causing damage to the hair cells of the inner ear 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. Tinnitus, on the other hand is typified by the ringing or similar sound in the ears caused by over stimulation of the hair cells. It can be acute of chronic, permanent or intermittent.

The main limitations of hearing protection, for part (b) are:

Poor fit. Resistance to use. Comfort factors. Incompatibility with other protective equipment. Costly in terms of replacement and maintenance. Interference with communications. Hygiene problems.

The need to constant supervision ad attention (unlike some engineering solutions to noise problems).

ELEMENT 8

1) Identify the main hazards that may be present during the demolition of a building (October, 2010) Some of the hazards that may be presented during the demolition of the building may include the following:

Unintentional collapse of the building being demolished or the adjoining structures because of the lack of temporary support, build up of debris, weakening of load bearing sections etc.

Debris falling from height during the demolition Fires, explosion, electrocution etc. due to services not being isolated Health hazards from chemicals, asbestos, lead based coatings, biological contaminations

etc. Personnel falling due to unsafe place of work or due to improper access / egress Hazards related to the use of explosives Hazards related to the manual handling of heavy loads

2) A three meter deep trench has to be dug across a car park

(a) Identify the hazards associated with the work

(b) Outline the control measures that could be implemented to reduce the risk (August, 2010)

(a) Hazards associated with work may include:

Unexpected collapse of the trench wall /cave in Falling of persons / workers into the trench Presence of toxic gases during the trenching Accumulation of water Fire due to the presence of underground utilities carrying flammable materials Collapse of the adjacent structure No proper access/ egress Mobile equipments falling into the pit

(b) To avoid the unexpected collapse of the trench / excavation wall, the wall should be protected by means of sloping, shoring, benching or shielding. Check for the presence of underground utilities before the start of the work. The perimeter of the excavation should be protected by means of hard barrication so as to avoid the unauthorized entry of personnel into the

work area and to avoid the vehicles running close to the excavation. The pit / excavation should be monitored to detect the presence of toxic gases as well as the availability of oxygen. Accumulated water inside the excavation / trench should be removed and protected against the runaway water. Proper lighting and caution boards should be provided in and around the excavation area.

3) Identify the precautions that should be considered to prevent accidents to children who may be tempted to gain access to a construction site. (June, 2010)

Some of the precautions that should be considered to prevent the entry of the children into the construction sites are:

Fencing / Barricading the site Fencing / Covering excavations/ trenches Display of warning signs and caution boards Visiting the neighborhood and informing the parents about the work activities Visiting the schools and conducting awareness programs Monitoring by the use of security patrols and closed circuit televisions Posting caution boards near excavated pits and dangerous machinery Removing ladders and denying access to the scaffoldings

4) The water main supplying a school is to be repaired. The work will be carried out in a 1.5 meter deep excavation, which will be supported in order to ensure the safety of those working in the excavation.

(i) Identify when THREE main inspections of the supported excavation should be carried out by a competent person.

(ii) State the information that should be recorded in the excavation inspection report.

(iii) Other than the provision of supports for the excavation, outline additional precautions to be taken during the repair work in order to reduce the risk of injury to those and others who may be affected by the work.

For part (i), candidates seemed unaware of the specific occasions when inspections must by carried out. These are at the start of every shift before work commences, after any event likely to affect the strength or stability of the excavation, and after ay accidental fall of rock or earth or other material. Candidates generally referred to the inspection of the excavation at the start of every shift but not to the other two main inspections.

Part (ii), should have provided candidates with the opportunity to gain marks simply by stating the information that should be contained in an inspection report. The opportunity was not taken by many. What was needed was reference to information such as the name and address of the person for whom the inspection was carried out, the location of the place of work, a description of the place of work inspected, details of ay matters identified that could lead to risks to the

health or safety of any person, the action taken to reduce the risk, any further action that might be needed, the name of the person making the report, and the date and time of the inspection.

Part (iii), precautions that should be taken to reduce the risk of injury to workers include the detection of underground services, safe digging, preferable by hand, near to the services and the provision of adequate support for them once exposed; the isolation of the water supply to reduce the risk of flooding the excavation; ensuring the stability of adjacent buildings if this was though to be necessary; the provision of safe access in and out of the excavation and placing stop blocks to prevent plant from approaching too close to its edge; and using appropriate personal protective equipment such as head protection, ear defenders and safety footwear, close to its edge, and using appropriate personal protective equipment such as head protection, ear defenders and safety footwear. As for the possible risk of injury to others who might be affected by the work, there would initially need to be close liaison between the contractors and the school authorities to ensure, whenever possible, that work in the excavation was carried out outside school hours. Additionally, barriers would need to be erected to provide a safe walkway for teachers and children ad other members of the public and precautions would also have to be taken to ensure that materials and equipment were stored in a safe compound and plant immobilized when not in actual use.

While the standard of response to this part of the question was marginally better than for the first two parts, there were not many candidates who were able to outline a full range of additional precautions for those who would possibly be at risk.

5) Outline EIGHT precautions that should be considered to ensure the safety of children who might be tempted to gain access to a construction site.

Outline a hierarchy of measure beginning with attempts to prevent entry by the use of fencing and signs, and monitoring by the use of security patrols or closed-circuit television. This is followed by reference to the need, should entry be gained, to make the site itself safe by isolating services, reducing heights of materials, covering or fencing excavations, as well as removing ladders and denying access to scaffolding. Also consider further precautions such as securing tools, chemicals, equipment and vehicles.

6) Outline the particular hazards that may be present during the demolition of a building.

The main hazards associated with this type of work include:

Falls from a height. Falling debris and premature collapse. Use of explosives. Contact with and noise from equipment and heavy plant. Dust (possibly including asbestos) The possible presence of services such as electricity, gas and water.