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NEBOSH UNIT-IB Questions ANS Matrix S. No. Questions AND Answers Dates Element IB1: Principles of chemical control, toxicology and epidemiology (old IB2) 1 RRC IB2- LAQ3 / 1 Human epidemiology and animal studies can be used to investigate whether a substance is carcinogenic. (a) Outline the advantages of EACH of these methods. Marks:3 (b) Outline the disadvantages of EACH of these methods. Marks:7 (a) The human epidemiology is a definitive method for identifying human carcinogens as it is based on experience in actual populations. Animal testing studies are the best experimental method as animals are closest biochemically to humans. There is no direct human risk with animal studies and data can be gathered more rapidly than with epidemiology. (b) Human epidemiology can be expensive and time consuming and usually requires large populations to reduce sampling errors that may otherwise distort the real, underlying picture. It is not a method to be deployed for assessing the carcinogenic potential of new substances because of the timescales involved, suffers from problems of sensitivity and specificity, and may rely on poor and inaccurate historical records. Animal studies can also be time consuming and expensive dependent on the type of animal needed. Apart from ethical considerations, there are difficulties in extrapolating animal data to humans and often very large doses are required to produce a response which may in any case vary with different animal species. Q3. July, 2011 July, 2008 (a) Explain why it is difficult to determine whether cancers in the working population are caused by exposure to substances used at work. (6) (b) Outline the merits and limitations of EACH of the following methods for identifying the carcinogenic potential of a substance: (i) human epidemiology; (5) (ii) animal studies; (5) (iii) in vitro mutagenicity (AMES) testing. (4) Or RRC IB2 - LAQ 1: Outline the techniques that can be used to investigate whether a substance for use at work may be carcinogenic, clearly identifying the advantages and disadvantages of each technique. (20) Q8. July 2012 JULY 2013

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NEBOSH UNIT-IB Questions ANS Matrix S. No. Questions AND Answers Dates

Element IB1: Principles of chemical control, toxicology and epidemiology (old IB2)

1

RRC – IB2-

LAQ3 / 1

Human epidemiology and animal studies can be used to investigate whether a substance is carcinogenic.

(a) Outline the advantages of EACH of these methods. Marks:3 (b) Outline the disadvantages of EACH of these methods. Marks:7

(a) The human epidemiology is a definitive method for identifying human carcinogens as it is based on experience in actual populations. Animal testing studies are the best experimental method as animals are closest biochemically to humans. There is no direct human risk with animal studies and data can be gathered more rapidly than with epidemiology. (b) Human epidemiology can be expensive and time consuming and usually requires large populations to reduce sampling errors that may otherwise distort the real, underlying picture. It is not a method to be deployed for assessing the carcinogenic potential of new substances because of the timescales involved, suffers from problems of sensitivity and specificity, and may rely on poor and inaccurate historical records. Animal studies can also be time consuming and expensive dependent on the type of animal needed. Apart from ethical considerations, there are difficulties in extrapolating animal data to humans and often very large doses are required to produce a response which may in any case vary with different animal species.

Q3. July, 2011

July, 2008

(a) Explain why it is difficult to determine whether cancers in the working population are caused by exposure to substances used at work. (6) (b) Outline the merits and limitations of EACH of the following methods for identifying the carcinogenic potential of a substance:

(i) human epidemiology; (5) (ii) animal studies; (5) (iii) in vitro mutagenicity (AMES) testing. (4)

Or RRC – IB2 - LAQ 1: Outline the techniques that can be used to investigate whether a substance for use at work may be carcinogenic, clearly identifying the advantages and disadvantages of each technique. (20)

Q8. July 2012 JULY 2013

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ANS (a) There are many reasons why it may be very difficult to identify whether cancers occurring in a population are caused by exposure to a substance used in a workplace.

First, cancers have a long latency period, so it may be very difficult to detect and trace cancers back to a particular workplace or type of work-related exposure.

Many cancers have multiple causes (not just occupation) making it almost impossible to exclude other possible causes that an individual may well have been exposed to during their life.

There may be synergism (e.g. smoking and asbestos exposure together) that is difficult to identify. Many cancers are common in the general population and therefore an occupational cause would be very

difficult to detect against this background prevalence. Individual factors (susceptibility) and poor records (exposure history, etc.) are two other reasons.

(b) Chemical Analogy – using expert knowledge about chemicals that have a similar structure and reactivity to the one under study to make predictions about the study chemical’s properties. Advantages – quick, economical, indicative. Disadvantages – not conclusive, restricted application. Any findings would have to be confirmed by other methods. (i) Human Epidemiology – making use of statistical analysis of historic data to link exposure to the substance to the risk of cancer.

Advantages – definitive method for identifying human carcinogens. Disadvantages –

Expensive and time consuming, Limited applicability (can’t really assess carcinogenic potential of new substances); Requires large populations (statistical validity); Relies on accuracy of historical records for substances currently in use; Problems with sensitivity and specificity (no test is 100% specific – can get false positives and false

negatives when testing the population to see if they have the disease).

(ii) Animal studies – using test animals of various species to determine and quantify the carcinogenicity of the

substance.

Advantages – best experimental method, data collected faster than by epidemiology Disadvantages –

Expensive/time consuming (although quicker than epidemiology);

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difficulties in extrapolating animal data to humans since large doses may be used Variation of effects between species of animal. Ethical considerations and adverse public opinion.

(iii)In vitro mutagenicity testing / Short-term Testing, e.g. Ames Test – quick, cheap, avoids ethical issues, mutagenicity is indicative of carcinogenic potential but raises issues of reliability (false positives and false negatives).

2 Stone masons are exposed to silica dust during grinding operations. You have collected exposure data for one worker using standard sampling equipment suitable for dusts. The results are presented in the table below.

Measurement type

Initial mass of clean filter

Final mass of filter and

collected dust Pump flow rate Duration

Respirable silica dust 262.15 mg 266.45mg 2.2 litres/min

4 hours (during the morning)

X-ray diffraction analysis of the collected dust sample has determined that the crystalline silica (quartz) content is 6% by weight

(a) OUTLINE the meaning of the term ‘respirable dust’. Marks:

(b) Using the data in the table, calculate in mg/m3 the average concentration of ‘respirable crystalline silica

(quartz) to which the worker was exposed during the sampling period. You should calculate the value in units of mg/m3 (there are 1000 litres in each cubic metre). Marks:5

(c) OUTLINE why there may be errors in the measurement values. Marks:3

ANS (a)

The term ‘Respirable Dust’ refers to dust which penetrates to the gas exchange region of the lungs. The respirable dust was typically less than seven microns in aerodynamic diameter.

(b) an average concentration of respirable crystalline silica during the sampling period of 0.49mg/m³. Total pump running time = 240 minutes giving a throughput of air of 528 litres (2.2 x 240) or 0.528m³ (528/1000). The mass of dust collected was 4.30 mg (266.45 - 262.15).

July, 2011

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The mean dust concentration was 8.14mg/m³ (4.30/0.528) and the mean crystalline silica concentration was 0.49 mg/m³ (0.06 x 8.14). (c ) Reasons for errors in the measurement values such as

Pump and balance calibration errors; Filter contamination; Variations in pump rate perhaps because of battery power variation and incorrect recording of either mass or

time.

3

RRC – IB1 -LAQ1

(a) Describe the structure of the skin and how hazardous substances may enter the body by this route. Marks:6

(b) Explain how contact (primary) dermatitis can occur. Marks:4

(c) A number of employees working in a hair salon have reported problems of skin irritation on their hands, which for at least one employee has been diagnosed as contact dermatitis. Advise the salon manager on the likely causes and the steps that could be taken to try to overcome these instances of contact dermatitis. Marks:10

Ans (a) The skin essentially consists of three layers:

Epidermis – the outer tough layer consisting of a horny zone of dead cells (continually being lost) together with a germinal zone below, from which these dead cells develop.

Dermis – true living skin containing blood vessels, sweat glands and nerve endings. Subcutaneous adipose tissues – fatty tissues used for storage purposes.

In addition, the epidermis benefits from protective layer of glandular secretions, sebum in particular, which affords a good degree of waterproofing. The skin is semi-permeable and some chemicals in liquid/solution form can go straight through it. This is particularly the case with organic solvents such as phenol, carbon tetrachloride and dimethyl sulphoxide (DMSO). Once through the skin these chemicals can then permeate the tissues beneath the skin and enter blood vessels. The skin route is particularly available if the glandular secretions are removed (e.g. by solvents or washing) and when hot/sweaty (pores/sweat glands open).

July, 2008

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Cuts/abrasions are another significant entry route. Here the defensive layers of the skin have been physically damaged, so any hazardous substance introduced to this area can come into direct contact with body tissues and the bloodstream. This is a particular risk with biological agents, as a very small amount of the agent may be enough to cause infection and the agent then reproduces within the body to cause disease. The final route of entry is very similar to the last, and that is direct physical injection through the skin, by puncture of the skin with a sharp object, such as a hypodermic needle (e.g. a needle stick injury) or by high pressure gas or fluid injection (e.g. from a burst hydraulic pipe). (c)Dermatitis in the Salon: Advice to the Salon Manager The hairdressing industry is a workplace where contact dermatitis is common. Essentially, dermatitis in this case is caused by frequent wet working; (washing/ shampooing/dying of hair) as well as from direct contact with the chemical irritants in shampoos, dyes, “perm” preparations, bleaching agents, sterilising fluids, etc. Such contact can occur directly (such as deliberately working without gloves) or accidentally (splashes to skin, touching contaminated equipment/clothing, etc.). Various factors affect whether a worker will contract dermatitis or not. Factors such as individual susceptibility (people’s personal response to wet working and dermatitic agents is different), frequency and duration of exposure, the presence of existing damage to skin, failure to wear gloves, etc. The steps that should be taken or considered to control the dermatitis include:

Pre-employment identification of susceptible individuals by health questionnaire or medical examination. Making sure that information on the risks of contact dermatitis is brought to the attention of all workers

through leaflets and training. Ensuring that substance information is available to all workers (in the form of MSDSs, etc.). Elimination or substitution, where possible, of the dermatitic agents. Job rotation to minimise the amount of time that workers have wet hands. Wearing protective gloves (non-latex) when wet working or dealing with chemicals (these must be of an

appropriate type and should be examined routinely to ensure they still afford protection). Drying hands properly and promptly. Using moisturising creams. Health surveillance in the form of regular visual checking of skin (for dryness, itching, cracking) followed by

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referral for workers with symptoms. In certain instances, workers with a pre-existing condition may have to be prevented from working with dermatitic agents.

4

RRC-IB01-SAQ1

The table below shows data provided in a supplier’s catalogue for three different grades of the same industrial chemical.

Product Code

Description

Average Particle

Size (microns)

Particle Size

Distribution

(Microns)

AS1/01

Fine white powder

15

12-20

AS1/02

Fine white powder

8

7-10

AS1/03

Fine white powder

2

1-5

Use the data to identify where EACH of these powders may be deposited in the respiratory tract following inhalation. In EACH case outline the mechanisms the body may use to defend itself. Marks:10 ANS The particle size will determine how far into the body the chemical will penetrate. For AS1/01, the particles are greater than 10 microns therefore they will enter the nasal cavity only. The nasal hairs will trap and filter out these particles. They may also be trapped by mucous in the nose and mouth and subsequently ejected by sneezing and coughing. As far as AS1/02 is concerned, particles between seven and ten microns reach the Respiratory track (trachea and bronchioles). They are swept upwards by tiny hairs - the ciliary escalator- towards the throat and are then removed either by coughing or swallowing. Particles smaller than 5 microns, as for AS1/03, are likely to reach the deep lung tissue. When deposited in the alveoli, they may diffuse directly into the blood stream and be transported to other organs, trigger a defence mechanism where phagocytes engulf the particulate as a foreign body and migrate away through the lymphatic channels or may stay in the spaces in the lungs and depending on their chemical properties may cause fibrosis or pneumoconiosis.

Q6.July, 2010

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5 (a) Describe the ways the body may defend itself against inhaled dusts. Marks:12

(b) A company uses a range of coloured powders in the manufacture of paints. These powders are added directly to a mixing vessel from sacks. The company is concerned about the level of exposure to its workers from the powders during this part of the process.

Outline the practical control measures that could be used to minimise exposure to these powders during the addition. Marks:8

ANS a) The body’s first line of defence against inhaled dusts is the nasal hairs which trap and filter out dust particles greater than ten microns in size. Mucus in the nose and mouth also traps these particles which are subsequently ejected by sneezing, blowing the nose and spitting. Dust particles between five and ten microns tend to settle in the mucus covering the bronchi and broncioles and are wafted upwards by tiny hairs – the ciliary escalator – towards the throat. They are then coughed and spat out. Particles smaller than five microns are more likely to reach deep into the lungs, as far as the alveoli. These particles are ingested by macrophages – a type of white blood cell – in a process known as phagocytosis and transported back to the ciliary escalator or to the lymphatic system. They may also be transported across the alveolar membrane into the blood stream. b) The elimination of the coloured powder was not an option since the colour range was required. Even some practical control measures could be taken to minimize the exposure such as

Introducing the colouring agent in a pellet or dye solution form. If this was not possible, then the powder could be fed into the mixing vessel by means of an automated feed system (such as a screw conveyor).

Local exhaust ventilation is also an option. A vacuum system would need to be introduced to clear up spillages and Employees should be provided with personal protective equipment such as overalls, gloves and goggles. Some

form of respiratory protection would also have to be provided. If the dust was thought to be nuisance only, then a particle filtering face piece – a disposable face mask –

changed on a regular basis could suffice. However, a mask and filter respirator would have to be worn if the powder were found to be harmful.

Adequate supervision to enforce use is important.

Jan, 2009

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Use of appropriate handling techniques to minimise dust creation when emptying sacks was also relevant.

6

RRC - IB2 – SAQ2

(a) Outline the following toxicological terms: (i) LD 50; Marks:2 (ii) LC 50. Marks:2

(b) (i) Outline the toxicity test known as the fixed dose procedure. Marks:4 (ii) Outline the possible reasons why the fixed dose procedure has replaced previous methods that estimated

LD 50. Marks:2 (a) LD50 is the dose at which 50% of test subjects die (administered orally or dermally). Given in mg of substance per kg body weight of test animal. LC50 is the concentration in air of airborne substance at which 50% of test subjects die. Specified in mg of substance per litre of air and typically an exposure period of 4 hours. (b) (i) The toxicity test is known as the fixed dose procedure, used to determine acute oral toxicity with a rat normally being used as the test animal. An initial study is carried out to determine the starting dose for the main study and this uses single animals and a successively increased dose to determine the range of toxic effects. The initial test dose for the main study is chosen as the dose which can identify toxicity without mortality. In the main study, an animal is tested at one of four fixed does namely 5, 50, 300, and 2000 mg/kg, with observation being carried out over fourteen days. The discriminating dose (i.e. That causes evident toxicity but not mortality) is determined and is used as the basis for classification such as very toxic, toxic or harmful or equivalent GHS classification. (ii) Possible reasons for substituting the fixed dose procedure for previous methods that estimated LD50 include the fact that a smaller number of animals is used; it uses morbidity rather than mortality as the end point; and it is considered more humane by many.

Jan, 2011 July, 2008

7 (a) Explain the meaning of the term ‘toxicity’. Marks:2 (b) Describe the physical characteristics of asbestos and give TWO occupational examples where it is likely to be

encountered. Marks:4 (c) Outline the diseases caused by exposure to asbestos AND their signs and symptoms. Marks:7 (d) Outline the equipment and method that should be used to determine the level of asbestos fibres in the air in

the workplace. Marks:7

Jan, 2011

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(a) The term ‘toxicity’ is a degree to which a substance is able to cause damage to an organism. Toxicity may be systemic or local, can be acute or chronic and can be divided into different classes such as, for example, carcinogenic. (b) Asbestos is a fibrous substance and occurs in different forms such as white (chrysotile), blue (crocidolite) and brown (grunerite). It is thermally very stable and is widely used as insulation material because of its fire resistance. It has good absorption qualities, is of average tensile strength and is chemically inert. Asbestos may be encountered in the removal of pipe lagging or in drilling into wall or roof panels. (c) One disease caused by exposure to asbestos is mesothelioma, a cancer that develops in the mesothelium, a lining covering major organs. It most commonly develops around the lung lining though the abdominal lining (peritoneum) may also be affected. Other diseases are cancer of the bronchus (lung cancer) and asbestosis, pneumoconiosis where scar tissue is irreversibly formed. Signs and symptoms are generally common to all the diseases and include chest pain, coughing, shortness of breath and emphysema. An additional symptom of lung cancer is spitting up blood while those of asbestosis are a progressive reduction in lung capacity and a pre-disposition to lung cancer. As far as latency is concerned, symptoms may not be apparent for some time. (d) The equipment that should be used to determine the level of asbestos fibres in the air of a workplace comprises a controlled flow sampling pump fitted with a filter head with cowl and a membrane filter to capture fibres. The method used follows a published standard and involves the calibration of the pump and drawing a known volume of air (calculated from time and the pump flow rate) through a membrane filter. The filter is removed after sampling and mounted on a microscope slide and the number of fibres counted. The concentration is calculated as fibres per ml from the fibres counted and the calculated volume of air used in obtaining the sample.

8 (a) Give the meaning of the following AND give an example: (i) carcinogen; Marks:2 (ii) mutagen. Marks:2 (b) A health and safety practitioner and an occupational health nurse are preparing a training presentation to be

given to workers who could be exposed to carcinogens in the workplace. Describe control measures specific to carcinogens that should be included in the presentation. Marks:6

(c) Other than assisting health and safety practitioners outline additional functions an occupational health nurse may have in a large organisation. Marks:10

July, 2010

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ANS (a) Carcinogen is an agent which has the ability to produce malignant tumours and which may attack the cell

reproduction mechanism. It causes changes in the cell’s DNA such as the production of abnormal cells with uncontrollable growth and its effects are irreversible, continuing well after exposure to the agent has taken place. A mutagen causes mutations or changes in the DNA of cells and the damage caused can be passed on to future generations. The damage to the cell may kill it and there is always the danger that it can in addition lead to cancer.

(b) it would be beneficial to begin the presentation (to workers be exposed to carcinogens) with An explanation of the nature of carcinogens such as their special properties and how they differ from

normal toxins. Information should also be included as to how they might be identified such as through labels with

reference given to warning phrases and hazard symbols that might be used. As for control measures, these would include limiting their use to a level as low as reasonably practicable

and by using a totally enclosed system. It would also be necessary to provide appropriate storage including the use of closed/sealed containers

which should, for transfer be labelled and securely closed. Areas where the carcinogens are used should be designated with identifying signs to indicate their

boundaries. Precautions should also be taken against contamination including the prohibition of eating and drinking in

contaminated areas and the provision of adequate washing facilities. While personal protective equipment such as overalls and gloves should be worn, Workers should be made aware that the equipment is only useful as a secondary control in combination

with other controls. (c)

The occupational health nurse would have an important part to play in carrying out a General assessment of health risks in the workplace, Preventing health problems and Promoting healthy working conditions.

The nurse’s functions might include among others, Health screening and surveillance; Providing first aid treatment or training others to carry this out; Interviewing workers following periods of sickness or on their rehabilitation; Taking part in pre-employment assessments; and Very importantly offering counselling and support when this is needed.

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9

RRC-IB4-

SAQ2

Describe the control measures that should be adopted when, because of the nature of the work, it is not possible to eliminate a carcinogen or substitute it with an alternative substance. (16) Specific control measures that should be adopted when it is not possible to eliminate a carcinogen or substitute it with an alternative substance include Reducing exposure to a level as low as reasonably practicable by minimising quantities used and/or

changing the physical form; The use of a totally enclosed system or automation of the process to physically separate workers from the

process and, where this is not possible, the use of a partial enclosure in the workplace or appropriate local exhaust ventilation.

It would also be necessary to provide appropriate storage including the use of closed/sealed containers and recognition that it may be better to store one large quantity in a controlled manner than to deal with frequent supplies of smaller amounts.

Materials would have to be correctly labelled and the areas of use restricted with identifying signs to indicate their boundaries.

Any waste carcinogenic products should be labelled and stored in a secure area pending removal by a specialist contractor.

The numbers working in the restricted areas should be minimised and non-essential personnel excluded. Precautions should also be taken against contamination including prohibiting eating, drinking and applying

cosmetics in contaminated areas; Providing appropriate warning signs to demark these areas; and Providing adequate washing facilities.

10.July, 2008 + carcinogen

/ mutagen def (4m)

RRC – IB4 – SAQ1

Outline a hierarchy of control measures which would be applied to carcinogens in the workplace. (10) Plan Eliminate, substitute, minimise amounts, total enclosure, LEV, control exposure, procedural controls, PPE, health surveillance, emergency. Suggested Answer A hierarchy of control measures that would be appropriate when using carcinogens in a workplace would be:

Eliminate the carcinogen where reasonably practicable. Prevent exposure, preferably by substitution for a non-hazardous substance or a considerably less

hazardous substance. Design and use work processes, systems and engineering controls so as to minimise the amounts of

carcinogens needed or produced as by- products.

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Control at source, by using totally enclosed systems or by the use of local exhaust ventilation systems. Use organisational measures to control numbers exposed and level/duration of exposure and

quantities used/stored in the workplace. Control the working environment (including using general ventilation). Prohibit eating/drinking/smoking in potentially contaminated areas. Clean surfaces (walls, etc.). Designate potentially contaminated areas and use warning signs. Use safe storage, handling and disposal methods (includes using closed and labelled containers). PPE (e.g. RPE) as a last resort (in addition to all the above). Health surveillance for exposed workers. Develop emergency and spillage procedures.

10 (a) Outline, using a relevant example, why and how a retrospective case control study is carried out. Marks:5

(b) Outline factors that affect the reliability of this type of study. Marks:5

Jan, 2008

11

RRC - IB2-

LAQ2

As part of a foam manufacturing process, a resin is mixed with a hardener that contains toluene di-isocyanate (TDI). Pre-employment screening is undertaken in order to exclude susceptible individuals. (i) Identify the possible health effects of TDI. (6) (ii) Identify the type of health screening that is likely to be conducted and outline the signs and symptoms that might lead to the exclusion of potential employees from the process. (4) (iii) Describe measures that could be taken to reduce the employees’ exposure to TDI. (10) ANS (i) Isocyanates can cause eye irritation, allergic dermatitis and respiratory sensitisation (leading to asthma). Allergic dermatitis is where the skin becomes sensitized to the isocyanate. This occurs over time, as a result of over-exposure to the solvent. Once sensitized, exposure to the solvent will lead to a whole skin reaction, i.e. the skin all over the body may become red, inflamed, itchy and this may lead to cracked skin, flaking, suppuration, etc. Respiratory sensitisation involves the same process occurring to the lungs through inhalation of solvent vapours. Once sensitised, any exposure to isocyanate vapour may bring on an asthma attack. (ii) Health screening – questionnaires (skin, breathing function), medical examination, health assessment (lung

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function). Signs/symptoms – existing allergies, asthma, predisposition to asthmatic conditions, depressed lung function. (iii) In order to reduce employee exposure to the TDI there are a range of options that might be considered:

Eliminate TDI and all other forms of isocyanate from the workplace. This might be done by moving to a totally new production process, or by buying in foam pre-manufactured, so that the isocyanate-dependant part of the process is avoided.

Substitute TDI for less harmful forms of isocyanate solvent, such as MDI or HDI. Apply an engineering solution and totally enclose the part of the process where TDI is handled and solvent

fumes are generated. This might be done by direct dosing of the solvent (rather than hand dosing) and by automation of plant.

If total removal of workers from the process is not possible, then total enclosure in a handling booth (so that workers who do not need to be exposed are not exposed) should be considered. In this instance, any workers who have to come into contact with TDI must wear PPE which would include appropriate gloves, apron, face protection and respiratory protection.

Minimisation of the quantities of TDI being handled is a very practical step. Local exhaust ventilation (LEV) must be applied to any enclosures where TDI is handled/exposed. This LEV must

be maintained, cleaned, inspected and tested. Training must be given to all employees on the hazards associated with TDI and the precautions to follow. This

would be particularly important, of course, to the employees who actually work with the solvent.

12

RRC-IB2-

LAQ2

A small motor vehicle repair workshop uses paints known to contain isocyanates. (a) Outline the health effects from exposure to isocyanates. Marks:3 (b) Outline the factors to consider when assessing the risks arising from using these paints. Marks:7 (c) Outline the practical measures to control exposure to the isocyanates when spray painting the vehicles in the

workshop. Marks:10

Q8 Jan 2013 Jan, 2011

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Element IB2: Hazardous substances and other chemicals – assessment of risk

IB3: HAZARDOUS SUBSTANCES – EVALUATING RISK

1

RRC-IB3 – SAQ1

(a) Use the data below to calculate the 8-hour Time-Weighted Average (TWA) exposure to a solvent for a factory worker. Your answer should include the detail of calculation to show your understanding of how the exposure is determined. Marks:7

Assuming that exposure is zero during all other times Also assume that a legally enforceable Exposure Limit (8 hours TWA) of 100 ppm is applicable to the solvent

(b) The factory decides to change the working patterns so that each worker does a single job for a 12-hour shift. A

factory worker is assigned the job of charging the mixers for his 12-hour shift. Within the shift he is allowed two 45 minute breaks where the exposure is assumed to be zero. (total break is 1.5 hours) Using the relevant data above, recalculate the equivalent 8-hour TWA exposure in the worker’s new role AND outline the legal implications of this change. Marks:3

ANS

(a) How the 8 hour TWA exposure to the solvent for the worker could be calculated: Firstly by multiplying together each time period and exposure including the periods of zero exposure, then adding the results of the calculations together and finally dividing by eight (8). This would give an answer of 75 ppm.

Numerically, this could be expressed as: ((140 x 2.5) + (0 x 0.25) + (100 X 2) + (0 X 1) + (25 X 2) + (0 X 0.25))/8 = 350 + 0 + 200 + 0 + 50 + 0 = 600 600/8 = 75 ppm. This is below the legally enforceable exposure limit of 100 ppm.

Working Period (Total shift time = 8 hours) Tasks undertaken by worker Exposure to

solvent (ppm) 08.00 – 10.30 Weighing ingredients 140 10.30 – 10.45 Break 0 10.45 – 12.45 Charging the mixers 100 12.45 – 13.45 Lunch 0 13.45 – 15.45 Cleaning equipment 25 15.45 – 16.00 Assisting maintenance staff 0

July, 2010 Jan, 2009

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(b), a similar calculation would have shown an exposure of 131.25 ppm viz: ((100 x 10.5) + (0 x 1.5))/8 = 1050/8 = 131.25 The change in the mode of working has increased the individual’s exposure so it is now more than the legal exposure limit and accordingly the employer is no longer adequately controlling exposure and must introduce additional controls.

2 Workers in a chemical plant are provided with gloves to protect against the possible effects of the chemicals. In recent months, there has been an increase in the number of hand and lower arm skin complaints amongst these workers. OUTLINE possible reasons for this increase in skin complaints. Marks:10 The possible reasons for the increase in skin complaints such as

- An incorrect initial selection of the protective gloves both as far as their material was concerned and their size and fitting;

- The fact that the gloves had degraded over time and had not been replaced or had been damaged either accidentally or intentionally with workers cutting off the finger ends to increase their dexterity / skill;

- The possibility of workers having an allergy to materials such as latex or the presence of excess perspiration following long periods of use;

- The failure to give the workers training in the methods to be adopted in putting on and removal of the gloves, and in the importance of self-examination, personal hygiene and the use of after-care products;

- A failure to clean gloves after use and to store them away from contaminants; - The absence of a system for reporting defects and replacing the protection; - Inadequate levels of supervision to ensure workers used the gloves at all times and finally the possibility that a

new chemical together with a change in process and work methods has been introduced.

1.Jan, 2011 JULY 2013

3

RRC – IB3-

SAQ2

Safety Data Sheets (SDSs) provide important information to employers who are required to assess exposure to hazardous substances in their workplace. A typical SDS is divided into sections that contain different types of information. Identify FIVE different types of information contained in a SDS, AND for EACH, outline how the information could contribute to the assessment of risk or control of exposure. Marks:10 (a) A SDS would include information on:

The substance name.

Jan, 2012

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Information on the hazardous nature of the product (its classification, such as toxic, together with Risk and Safety phrases) and toxicological data (such as LD50, carcinogenicity).

Information on the hazardous ingredients/composition (as opposed to the overall product). Physical and chemical properties (such as boiling point, volatility, physical form). Information on exposure controls/personal protection and standards (such as applicable occupational

exposure limits, glove breakthrough times and measures normally recommended to reduce exposure). Stability and reactivity data (such as identification of incompatibles). Measures to be taken in emergencies (spillage, first aid, fire).

(b) When assessing exposure to hazardous substances, the assessment must take account of numerous factors including How the task is carried out (e.g. pouring/spraying), Frequency and duration of exposure, Amounts used, Inherent properties (health, physical and chemical), Potential for accidental release (when exposure may be considerably greater) and the efficacy of any

existing controls.

The SDS is no substitute for a risk assessment, but it can provide some base data for it. Information on hazards will help to identify the inherent nature of the harm that can be caused in the first place (such as irritation or rapid destruction of skin) and the basic sites of attack (e.g. “harmful by inhalation”, “harmful if swallowed”). Physical data (such as form and volatility/dustiness) can help identify the realistic exposure potential for various routes (high volatility/dustiness means easily inhaled). Data on standards such as occupational exposure limits, etc. defines limits on what constitutes acceptable control for airborne contaminants (so gives a concrete exposure target to aim for). Recommendations on controls/PPE help choose appropriate controls to reduce/avoid personal exposure or compare with existing controls. Reactivity data informs decisions about how to avoid/limit potential higher exposure from unplanned releases (from undesirable reactions).

4

RRC IB3–

Operators use a range of solvents in a manufacturing process. Describe a monitoring strategy that could be used to measure the exposure of the operators to solvent vapours. Marks:10

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LAQ-01

HSG173 describes a three-stage approach to a monitoring strategy. In this case the strategy might consider people/areas to monitor, timing and duration of monitoring, how to monitor. There would need to be some basic data so that an initial evaluation of exposure level might be made. This initial evaluation might make use of simple grab- sampling data (stain tubes or other methods), and possibly other techniques might be used, to get quantitative data on exposures (including personal monitoring and biological monitoring). There would also be the need to consider the analysis methods to be used. This would require reference to MDHSs (Methods for the Determination of Hazardous Substances) and other recognised sources of standard methods

5 Workers manufacturing lead-acid batteries may be exposed to a range of hazardous substances.

(a) Identify the main hazardous substances likely to be in use. Marks:2

(b) Outline the control measures that should be in place to reduce the risks of exposure to the main hazardous substances in use in this process. Marks:8

ANS

(a) The hazardous substances likely to be used such as lead, lead oxide, lead dioxide, lead trioxide (red lead), lead sulphate and sulphuric acid

(b) Having established that elimination or substitution of the hazardous substances was not an option, the control

measures may be included Prohibiting vulnerable groups such as pregnant women, those of reproductive capacity and young workers

from working with lead; Designing work systems and processes, for example automation, to minimise exposure; The use of engineering controls such as exhaust ventilation and ensuring the controls were maintained and

their performance monitored at regular intervals; Prohibiting eating and drinking in contaminated areas and providing facilities free from lead for this purpose

and also for washing and changing; The provision and use of respiratory protective equipment to counter exposure to acid mist and lead fume; The provision of acid resistant gloves, goggles and face shields as a protection against acid splashes;

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Carrying out regular atmospheric monitoring for the presence of lead and acid mist; Introducing procedures for medical surveillance including testing for the presence of lead in blood and

providing workers with information, instruction and training on the risks associated with the process and the control measures that should be taken.

There were only a few candidates who seemed to have any understanding of the process of manufacturing lead acid batteries and those who did have the knowledge, did not outline all the control measures necessary often omitting to refer to vulnerable groups, minimising exposure and the reasons for providing RPE.

6 A factory produces a range of painted and varnished furniture. Outline the factors to be considered when assessing the health risks to employees from exposure to solvents in this factory. Marks:10

The health risks from exposure to solvents are determined initially by how the substances can enter the body (eg inhalation, skin absorption) and by the effects that they might cause (eg dermatitis, toxic effects). The physical properties of the materials (volatility in particular), the quantities used, the frequency and duration of exposure, and the work methods employed will determine the level of exposure or dose. In the scenario given, it is foreseeable, for example, that the range of painted and varnished finishes may be applied by brush or by spraying and each method will result in differing levels of exposure and therefore present different levels of risk. When making any assessment of risk it is necessary to consider who is being affected. This is in terms of the number of individuals exposed and also whether there are any individuals who are at particular risk. In this scenario, those with certain pre-existing health conditions and pregnant workers may require special consideration. An assessment of health risks needs to be based on good information. Much of this can be found in written form from manufacturers’ material safety data sheets but other sources (eg published guidance) may also need to be referred to, in particular to identify whether any of the solvents in question have been assigned exposure limits.

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If there are multiple exposures to different solvents, then additive effects will need to be taken into account. Synergistic effects may also be a possibility, although more difficult to determine. Analysis of health records and recorded incidents of ill-health will also form part of a proper assessment. Finally, the assessment should consider existing control measures in terms of their nature and adequacy. However, this is only one issue amongst a wide range of other risk factors.

7

RRC – IB3 – LAQ2

Workplace Exposure Limits (WELs) are a type of Occupational Exposure Limit (OEL) used in the UK. (a) Define what is meant by a WEL and outline the criteria upon which they are set. (8) (b) Discuss the limitations of accepting the control of hazardous substances solely on the basis of minimal compliance with a WEL.(12)

(a) A WEL is defined as the maximum concentration of an airborne substance, averaged over a reference period, to which employees may be exposed by inhalation. Two reference periods are used - either 15 minutes or 8 hours, referred to as the short-term exposure limit (STEL) and the long-term exposure limit (LTEL) respectively. A WEL value is set at a level at which no adverse effects on human health would be expected to occur, based on the known and/or predicted effects of the substance. This prediction is based on animal studies in most instances and sometimes on human epidemiological data. Where such a level cannot be identified with reasonable confidence, or is not reasonably achievable, then the WEL value is based at a level corresponding to what is considered to represent good control, taking into account the severity of the likely health hazards and the costs and efficacy of control solutions. Wherever possible, the WEL is not set at a level at which there is evidence of adverse effects on human health. (b) Simply achieving minimal compliance with the WEL will not guarantee legal compliance and it will not guarantee that employees are not being overexposed to hazardous substances that may be damaging their health. There are many reasons why simply working to minimal compliance cannot guarantee health and they vary depending on the nature of the substances and the exposed individual. The reasons are detailed below:

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WELs take into account inhalation only, i.e. they are intended to act as OELs for airborne contaminants only. If a substance is able to enter the body through alternative routes, then compliance with WELs will not guarantee safe exposure. For example, phenol can be absorbed into the body through the skin. Phenol concentration in the atmosphere may be so low as to remain below WELs on all occasions. However, if phenol is splashed onto the skin, the skin absorption route may be enough to deliver a lethal dose to the worker.

In other instances there is no known safe level of exposure. This is the case for carcinogens, mutagens and

asthmagens. Where these chemicals are concerned the only safe level of exposure is zero; above zero risk exists (albeit very low risk). Consequently the law clearly indicates that control of exposure to carcinogens, mutagens and asthmagens will only be considered under control if the exposure by inhalation is to the lowest level reasonably practicable (not just under the WEL).

There can be great variations in individual susceptibility to hazardous substances. Consequently, adopting the

WEL approach may not ensure protection for all employees. Asthmagens are an example where low levels of exposure can severely affect a susceptible individual. In these instances, that individual will have to be removed away from any potential exposure. Another issue to consider is that these standards are all set based on the available scientific evidence. There is not complete agreement on the scientific evidence and consequently it must be recognised that WELs are not perfect standards.

There will also be inevitable variations in control within a workplace. Controls may be very good one day and then not work as well the next. If monitoring and assessment is carried

out during good periods and exposure is just below the WEL; then during times when controls are not working so effectively the WEL will be exceeded.

Any determination of exposure levels will be subject to variation (it is not possible to apply laboratory precision in most real world workplaces) consequently there are inherent inaccuracies in readings taken in the workplace. Finally, there are issues associated with possible synergistic effects of different substances (where one exposure causes a greater effect from a simultaneous exposure). Since these possible synergies are not considered when setting

WELs, they may go unnoticed in the workplace despite the fact that independent WELs are being adhered to.

8

RRC – IB3 – SAQ1

(a) Describe the physiological effects of carbon monoxide on the body and identify the symptoms that may be experienced by an exposed person. (4) (b) Outline the control measures that could be used to reduce levels of carbon monoxide in motor vehicle premises. (6)

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Plan (a) CO and haemoglobin; headache, weariness, unconsciousness. (b) Eliminate, substitute, reduce production, LEV, workplace ventilation, PPE, maintenance of controls. Suggested Answer

(a) Carbon monoxide is an invisible gas which forms part of the exhaust fumes from vehicles. The initial symptoms are

giddiness, a sense of oppression in the chest and loss of power in the lower limbs, then the victim will fall to the ground and lose consciousness.

Concentrations of about 5% will cause immediate unconsciousness. Coma and death will follow rapidly. The gas is inhaled into the lungs and then absorbed into the blood stream, where it combines with hemoglobin carried within red blood cells. Carbon monoxide molecules bind to the active site of each haemoglobin protein molecule, thus preventing the haemoglobin from carrying oxygen. In this way the blood becomes saturated with carbon monoxide and cannot carry any oxygen around the body. Asphyxiation follows rapidly.

(b) The usual method of controlling the exhaust fumes is by Local exhaust ventilation; a flexible hose is fitted over the exhaust pipe and the fumes are sucked away by fans and ducts to atmosphere. This system requires:

o Training for workers on correct use; o Development of procedure to ensure that it was used at all appropriate times and o Regular inspection, maintenance and testing to ensure ongoing effectiveness.

Other methods of control are to provide plenty of general workplace ventilation, e.g. having the garage doors wide open, or having powered fans fitted to the building to force fresh in or exhaust air out of the building.

The length of time that vehicles are left with engines running should be minimised. A carbon monoxide alarm would give early warning of increasing carbon monoxide levels.

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Element IB3: Hazardous chemicals – engineering controls and personal protective equipment

IB4: HAZARDOUS SUBSTANCES – PREVENTIVE AND PROTECTIVE MEASURES

1 When respiratory protective equipment is in use, it may not provide the level of protection stated by the manufacturer. Outline the possible reasons for this. Marks:10 The possible reasons include

- An inadequate initial assessment which did not take into account work rate, duration of wear required and the anticipated level of contamination;

- A poor air flow or a loss of battery power; - The fitting of incorrect cartridges or a failure to replace them before saturation; - Poorly fitting equipment or incompatible with other personal protective equipment being worn; - The presence of other contaminants resulting in a decrease in saturation time; - Inadequate training in its use and particularly in the care that should be taken in its removal; - Poor maintenance and inadequate storage resulting in the face piece being left exposed; - Damage occurring during use and inadequate monitoring and supervision to ensure the equipment was

always used when required and - The fact that the equipment might not have been manufactured to the appropriate standards, - The considerations to be taken when selecting respiratory protective equipment rather than why,

once selected, it might not provide the stated level of protection.

July, 2011 July 2007

2 RRC-IB4 – SAQ3

An airborne contaminant has an Occupational Exposure Limit (OEL) of 10ppm, 8-hour time-weighted average (TWA). Engineering controls have been introduced but the airborne concentration of the contaminant in a workshop has been measured at 180ppm, 8-hour TWA. The occupational hygienist has selected a piece of respiratory protective equipment (RPE) with an assigned protection factor (APF) of 20, which is to be worn temporarily by all workers in the contaminated area.

(a) Using the data above outline how the hygienist could have calculated the APF AND whether the hygienist made an appropriate selection. Marks:4

(b) OUTLINE other factors that should be taken into account when selecting appropriate RPE. Marks:6

(c) When RPE is used it may not provide the level of protection stated by the manufacturer. Outline the possible reasons for this. Marks:10 ANS of Q1

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ANS (a) The assigned protection factor (APF) of an item of respiratory protective equipment is the concentration of contaminant in the air divided by the concentration in the face piece. In the scenario described, the maximum concentration in the face piece to which a worker should be exposed would be the occupational exposure limit (OEL) – 10ppm. Therefore the minimum APF required would be 180/10 =18. An alternative way to arrive at the same answer was to recognise that an APF of 20 would result in a concentration of contaminant in the face piece of 180/20 = 9 ppm which is within the OEL of 10 ppm. The hygienist has therefore made an appropriate selection though respiratory protective equipment with a higher APF might be chosen to provide an increased factor of safety. (b) Lots of factors must be taken into account when selecting RPE. For example:

The nature of contaminant; is it a dust, vapour, etc., is there an occupational exposure limit, is the contaminant a carcinogen, mutagen or asthmagen and is it toxic on inhalation?

What is the expected duration of use of the RPE? Short duration use might allow the selection of a lower quality item whereas long–term or continual use will require a much higher specification item to be used.

What is the type and nature of the work being carried out when wearing the RPE? Is it heavy or light work, what degree of movement is needed, are there space constraints that might prevent the use of larger bulky items?

Are there compatibility issues with other PPE needed? If so, how can these issues be overcome without compromising the effectiveness of all PPE items?

What about ease of maintenance? Some items of RPE require a high level of maintenance and therefore should only be selected where this maintenance is available and adequately resourced.

What standards exist for the RPE and does it meet those standards? i.e. certified to the relevant international standard.

What is the nature of the workforce? Are they capable of using the chosen items to an acceptable standard and have they been consulted and involved in the selection (user acceptability)?

3 A slightly corrosive solution is used as a treatment in part of a manufacturing process. The solution is applied by hand brushing. For this process, other methods of application are not practicable.

(a) Outline the factors that should be considered in the selection of personal protective equipment to adequately protect the skin and the eyes of those involved in the process. Marks:10

(b) Outline the content of a training programme that will assist workers to use the personal protective equipment

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correctly. Marks:5

(c) Identify a range of practical measures (other than training) that can be taken to encourage the use of the personal protective equipment and maintain its effectiveness. Marks:5

ANS (a) The factors to be considered in the selection of personal protective equipment firstly for the hands, then for the face and eyes and finally for the rest of the body. For the selection of protective gloves, relevant factors were

The chemical resistance to the corrosive solution and the chemical breakthrough time; The length of time that the gloves had to be worn; The level of dexterity required for the task; The length of the glove to afford adequate protection; The durability of the gloves; The need to ensure that a suitable range of sizes is available for the various users; and any worker allergies to

the glove material or any other skin problems. In the selection of eye protection, relevant factors were

The risk of splashing the face as well as eyes; The provision of advice on the use of goggles or a face shield with the appropriate level of chemical resistance

and not glasses; and Their compatibility with other protective equipment if this was required.

In the selection of body protection,

Aprons and/or overalls and appropriate footwear. Consultation and user trials; Comfort of the equipment;

Reference to legislation and ILO guidance and ensuring that that all personal protective equipment provided met the appropriate standards. (b) Workers should receive training in topics such as:

The health risks of the chemical in use; The type of personal protection to be used and the reason for its use; The methods to be used for putting on and taking off the equipment without causing contamination including

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decontaminating or discarding gloves after use; The methods of examining the equipment for damage or degradation, particularly gloves, and The methods for reporting defects and obtaining replacements; How to store the equipment correctly and Finally how to carry out self-examination of the skin and the action to be taken if problems were to occur.

(c) Practical measures to be taken to encourage the use of the personal protective equipment and maintain its effectiveness such as :

Management leading by example; Workers being involved in the selection of the equipment; Ensuring the availability of a range of sizes in gloves and fully adjustable face shields; Ensuring workers were required to sign for their equipment and maintaining records of issue; Issuing the equipment on a personal basis and providing adequate storage facilities; Using propaganda, signs and posters and incentive schemes; Monitoring compliance in the use of the equipment with a recognized code of discipline for non-use; and Finally monitoring the effectiveness of the equipment issued and replacing it with an alternative type if

problems were encountered.

RRC-IB4 – LAQ1

Describe the factors to consider when selecting, using and maintaining personal protective equipment to protect the hands and arms against a degreasing solvent. 20 M

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4 RRC-IB4 – LAQ2

(a) Outline the routes of entry and the possible effects on the body when someone is exposed to high levels of lead. (6)

(b)Outline the risk control measures that a lead-acid battery manufacturer should have in place to adequately control the risks of exposure of their employees to lead. (14) (a)Inorganic – inhalation.

− Nausea, vomiting, headaches. − Anaemia, muscle weakness, kidneys. Organic – inhalation and skin. − Muscles, mania, coma.

(b)

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(b)In order to adequately control the risks of exposure of employees to lead, first of all a risk assessment must be done. Elimination/ substitution of the lead should be considered, though it is very likely that it is not reasonably practicable in this scenario. Lead-acid battery manufacture may involve exposure to lead through: manipulation of lead oxides; mixing/pasting; casting/melting of lead; trimming/abrading of pasted plates. Controls will include (in no particular order):

Enclosing the process where possible. Changing work methods so that they minimise the generation of lead dust/fumes. Arrangements for safe handling, storage and transport of lead and lead waste (e.g. sealed containers). Reducing numbers of people exposed and their level/duration of exposure to a minimum. Minimise inventory of lead held at the workplace. Use of general dilution ventilation and LEV to control airborne concentrations. Regular cleaning of workplace (so lead dust doesn’t accumulate). Hygiene measures (washing hands before eating – use of nail brushes, facilities for laundering and changing

clothes (contamination)). Prohibiting eating/drinking/smoking in contaminated areas. Provision of PPE (RPE, gloves, etc.) where necessary. Enforcing use of control measures. Monitoring airborne concentrations (where exposure is likely to be significant). Medical surveillance with blood/urine lead levels and action taken if limits exceeded. Maintenance. Training/information. Emergency procedures. Young people and pregnant workers should not be permitted to work with lead in lead-acid battery

manufacture processes.

5

Workers cutting and finishing stone are exposed to stone dust. Stone dust has been assigned a legally enforceable Occupational Exposure Limit (OEL).

(a) Give the meaning of ‘Occupational Exposure Limit’ (OEL). Marks:3

(b) Explain the factors to be considered when undertaking a suitable and sufficient assessment of the risks from exposure to stone dust. Marks:11

(c) Outline a suitable range of control measures that could reduce the risk to these workers from exposure to

stone dust. Marks:6

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ANS (a) An occupational Exposure Limit (OEL), is the maximum concentration of a substance to which workers may be

exposed by inhalation. The concentration is measured in mg/m3 or ppm and is averaged over a reference period, either long term over a period of eight hours intended to control effects by restricting the total intake by inhalation over one or more work shifts, or short term, usually fifteen minutes, to control effects that may be seen after a brief exposure. For the control of stone dust to be adequate the OEL should not exceeded and the principles of good hygiene practice should be followed.

(b) In undertaking an assessment of the risks from exposure to stone dust, factors to be considered include

The health effects of the dust such as irritation to the skin, eyes and respiratory tract (physical structure such as crystalline or amorphous may also have a bearing on longer term health effects);

The number of persons exposed, the level, duration and frequency of their exposure and the susceptibility of individuals such as to asthma;

The routes of entry of the dust such as through inhalation or ingestion; The particle size of the dust which will determine how far into the body the dust will pass; The way in which the work is carried out whether by hand or power tool; The level and effectiveness of existing control measures and results from the monitoring of

airborne contaminants and their comparison with the OEL together with the results of health surveillance.

(c) As for suitable control measures, for operations carried out in a workshop,

The use of local exhaust ventilation would be required but for outside work damping down would be the measure that would have to be used.

Controls to be used in both situations include the use of cutting tools with in-built extraction or a damping spray;

The provision and use of respiratory protective equipment (RPE) which should be comfortable to wear for extended periods of use, and compatible with other personal protective equipment such as eye and hearing protection, gloves and overalls; and

Facilities both for washing, changing and for the laundering and storage of overalls. RPE users should also be subject to face-fit testing and the RPE itself properly cleaned and

stored when not in use. Training for workers on hazards and precautions was also relevant.

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RRC-IB4-

LAQ 3

Stonemasons are exposed to irritant limestone dust in the course of their work. Limestone dust has been assigned a workplace exposure limit (WEL) in accordance with UK legislation.

(a) Explain the term Workplace Exposure Limit (WEL) in this context.(3) (b) Stonemasons’ work involves both cutting and finishing of limestone. Explain the factors to be considered when undertaking a suitable and sufficient assessment of the risks from their exposure to limestone dust. (11) (c) Given that stonemasons are required to work both in a workshop and out on site, suggest a range of control measures that would be suitable in each of these situations. (6)

6 It is often necessary to monitor a worker’s personal exposure to hazardous substances using a variety of methods including: gravimetric analysis; microscopy; chemical analysis. For EACH of these three measurement principles:

(a) Identify a type of hazardous substance, AND suggest a typical workplace situation, where such a measurement may be necessary; Marks:6

(b) Outline the type of equipment and the methodology used to determine the worker’s personal exposure to the hazardous substance. Marks:14

(a) The gravimetric method for measuring personal exposure to hazardous substances may be used for measuring total inhalable or respirable dusts for instance in a woodworking workshop or in the manufacture of chemicals. Microscopy would be used for the measurement of fibers such as following the accidental disturbance or planned removal of asbestos. Chemical analysis is used in the measurement of gases, vapors, fumes and some dusts in workplaces such as laboratories or those involved in the manufacture of chemicals. (b) With gravimetric, a filter on a sampling head attached to a pump is used. There are various types of sample head depending on the type of dust being determined (e.g. 7 hole, IOM and the cyclone). The filter is weighed before and after sampling and the concentration, expressed in mg/m³, is determined from the weight gain and the volume of air drawn through the pump during the sampling period. With microscopy, a membrane filter fitted on an appropriate sampling head (e.g. cowled) is attached to a pump. After sampling is completed, a phase contrast microscope is used to count the fibers. The number of fibers in a known

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proportion of the sample is calculated and extrapolated to the whole sample with the result being expressed as fibers per milliliter of air (f/ml). As far as chemical analysis is concerned, there are numerous active and passive collection devices. For example, a tube or sampling head with a filter impregnated with an adsorbing material such as charcoal, tenax or silica attached to a pump. After sampling it is desorbed and analyzed in a laboratory. Analysis techniques include mass spectrometry, spectrometry and gas chromatography. Concentrations are expressed in parts per million or milligrams/m³. General points associated with each monitoring method include the necessity: to calibrate the pumps used; to draw a known volume of air through the filter or tube; to take a number of samples to minimize errors in measurement; and to ensure the sampling head was placed in the breathing zone.

7 A company is considering substituting a solvent it currently uses for one that is thought to be more effective. Outline the factors that should be considered before a decision is taken to make the change. Marks:10 The information that would enable a comparison to be made between the risks from the proposed substance with those of the existing one.

- Much of this information might be gained from the manufacturers’ safety data sheets for both substances. - Specific information on the proposed substance would relate to:

The physical form of the substance (eg whether aerosol or liquid); The possible routes of entry of the substance into the body; Its flammability and volatility; Its short and long term health effects; Applicable exposure limits such as WELs; the quantity of the substance that would be used; The number of persons likely to be exposed and the level and frequency of their exposure; Personal susceptibilities of those involved with particular reference to workers who might be especially

vulnerable such as young persons or workers with a liver or heart condition; Additional control measures that might be required; Storage arrangements for the solvent particularly in the light of its potential flammability and

combustibility; The procedures that might have to be introduced for the disposal of the substance and for dealing with

any emergency; and Financial issues such as the cost of providing adequate protection such as respirators and gloves.

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8 Outline the main design features of the following parts of a Local Exhaust Ventilation (LEV) system: (a) inlet/hood; Marks:2 (b) ducting; Marks:3 (c) fan; Marks:2 (d) outlet / exhaust. Marks:3

ANS (a) It should have considered features of the inlet or hood such as its shape and size, the material of its construction, its capture and face velocity and its positioning in relation to the contaminant source. (b) As for ducting, there would be a need to address its internal finish and the nature of its bends, the material of its construction, its transport velocity and the access provided for testing and maintenance. (c) The type of fan required whether centrifugal or axial and propeller giving reasons for the choice, the speed and power required and the possibility of the level of noise it might produce. (d) As for the outlet or exhaust, design features include its positioning, the avoidance of cowls, its ability to achieve environmental standards at the point of discharge and again the level of noise that might be produced.

July, 2010

9 RRC –

IB3 LAQ3

In a chemical process, workers use a mixture that contains two organic liquids, MMA and PPO. Table 1 below shows the average personal exposure levels to the organic liquids for one worker measured over an 8-hour day and Table 2 shows the exposure limits for the two components (MMA and PPO). Table 1 Assume that exposure is zero at all other times.

Task undertaken by worker Duration of task

Exposure to MM (PPM)

Exposure to PPO (ppm)

Measuring out and adding mixture

to process vessel 15 minutes 70 200

Adding other components to the mix

1 hour 20 200

Supervision of mixing 2 hours 35 200 Transfer of product to containers 2 hours 40 200

Q9. July 2012 JULY 2013

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Substances in a mixture may interact in different ways to cause harm.

(a) Outline what is meant by independent, additive and synergistic interactions. (4)

(b) Using the information in Table 1, calculate the 8-hour Time- Weighted Average (TWA) exposure of the worker to BOTH MMA AND PPO. (8)

Your answer should include detailed working to show you understand how the exposure is determined.

(c) Using relevant information from Tables 1 and 2, explain what actions might be required by the employer to control exposure. Assume that the components have independent toxic action. (8)

a) Independent means the action is on different organs or tissues (or different mechanism); additive means they act on the same organs/tissues (or similar mechanism); and synergistic is where the combined effect is considerably greater than the sum of the individual effects. had few problems with the calculations in part (b), easily evaluating the MMA concentration as 23.4ppm and PPO as 131.25ppm. For part (c), candidates needed to note that neither the MMA nor the PPO time weighted average concentrations exceeded their respective exposure limits (long-term or short-term). It was important to explain this by reference to the data in the tables. That established, other actions may still be needed. For example, more detailed/extensive measurements to confirm the result was true for other areas and employees. The assumption of independent action may also be invalid, so may require investigation. Other components are also mentioned (in the second step) and these might need to be measured. In any case, routine periodic monitoring should be undertaken going forward.

Substance Exposure limit Long-term exposure

limit (8-hour TWA limit reference period)ort-

term exposure

Short-term exposure limit (15-minute

reference period) 15-minute

MMA 50 100 PPO 200 250

10 (a) Outline why it is important to measure transport (duct) velocity when assessing the efficiency of a local exhaust ventilation (LEV) system. Marks:2

(b) Outline the methods that can be used to measure transport velocity in an LEV system. Marks:5 (c) Identify other measurements that can be used to determine if the LEV system is working as designed. Marks:3

Q6. Jan 2013 Jan, 2011 Jan, 2009

11 Outline the mechanisms by which the body may defend itself against harmful exposures to chemical substances. Marks:10

Q2. Jan 2013 July, 2007

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Element IB4: Monitoring and measuring

IB5: HAZARDOUS SUBSTANCES – MONITORING AND MAINTENANCE OF CONTROL MEASURES

1

RRC-IB4-

SAQ1

Outline the tests that could be used to assess the efficiency and effectiveness of local exhaust ventilation systems. (10)

LEV depends on the flow of air into the hoods, up the ducts and through any filters; The clean air is then passed out to the atmosphere. The presence of the airborne contaminant that is supposed to be controlled by the LEV might be assessed. This might be done by conducting static sampling or personal dosimetry in the work area that the LEV extracts from. Visual assessment of the areas might also be made (e.g. by looking for excessive build-up of dust on surfaces in a workroom which would indicate the LEV is not working well). Qualitative assessment of the LEV infeed efficiency might be made by either using a Tyndal beam to visualize particulates, or using a smoke generator to track air flow into the hoods. Pitot-static tubes and manometers can be used to measure the static pressure at the hoods and in ducts. The velocity of the flow of air can be measured to ensure that the particulates are not sticking to the sides of the ducts. This might be done using anemometers of various types (e.g. heated head or hot wire type). Flow meters can be used to measure the volume of air passing through the fans. Other tests can be carried out to test the effectiveness of the filters. This might be done using simple manometers to ensure those filters are not going blind (becoming clogged). Tests might be carried out on the purity of the cleaned air on the exhaust side of the ducts.

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2

RRC-IB5-

SAQ3

You have been sent a copy of a “local exhaust ventilation (LEV) examination report” conducted by an external organisation and relating to an LEV system in one part of your company’s production area. You have been asked by the production manager to comment on the suitability of this report, before the company goes ahead and commissions further LEV examination work throughout the rest of the factory. Outline the issues you would need to consider when assessing the adequacy and quality of the report in order to provide relevant comments to the production manager. (10) A record of LEV inspection and test should at least cover:

Identification of the LEV plant, process and substance(s) being controlled with some reference made to the appropriate local standards.

The date of last examination and test. The LEV’s intended (design) performance specification. The current LEV performance (as ascertained by a range of techniques, with results; e.g. static pressure, face

velocity, dust lamps, visual inspections, etc.).

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A clear indication as to whether any improvements/repairs are needed (which will depend on an analysis of current performance relative to design and taking account of any standards).

The date of examination/test. The name of person (and their employer) doing the test, along with any relevant credentials (qualifications,

accreditations). Reference to appropriate methodologies, standards and details of any calibrations carried out on technical

equipment used. The requirement to keep the record for an appropriate period of time. All of these factors would be used to

assess the adequacy of the LEV report, along with general impression of the report and whether it was legible or not.

3

Organic solvents, which are classified as harmful and sensitising, are used as a thinning agent for paints which will be used by workers.

(a) Outline the principles and methodology of the following air monitoring techniques used to assess the workers’ exposure to the organic solvents:

(i) grab sampling using a direct reading instrument; Marks:4 (ii) active static sampling; Marks:4 (iii) active personal sampling. Marks:4

(b) Outline the strategy to be used in the prevention and control of exposure to the organic solvents. Marks:8

(a) (i) Grab sampling with a direct reading instrument, a stain tube detector connected to a bellows or hand piston pump and specific to the contaminant being sampled, would be used. A known volume of air would be drawn across a chemical reagent in the tube and the organic solvents in the air sampled would react with the reagent causing the stain colour to change. The concentration of organic solvent in the sample area may be read off directly from the degree of colour change. (ii), The technique of active static sampling can be used to assess the general level of organic solvents in the environment and may also assist in assessing the effectiveness of any engineering controls provided. A mains/battery operated pump is used with the solvent being absorbed onto or into a suitable sorbent and it is important to place the equipment in strategic positions around the workshop. (iii) The technique of active personal sampling is used to estimate a worker’s level of exposure during a shift. A sampling device connected to a low or constant flow sample pump is worn in the worker’s breathing zone.

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(c) The organic solvents are absorbed onto an absorbent medium whether liquid or solid, and chemical analysis is used to measure the quantity of organic solvent absorbed. In devising a strategy for preventing or controlling exposure to organic solvents,

Consideration would have to be given to the substitution of the solvents with substances that are less hazardous and to changing the method of applying the paint particularly if it is currently sprayed.

It might also be possible to isolate the process and to minimise the number of workers exposed to the solvents by reducing both the quantity of paint used and the exposure time of the workers.

A local exhaust ventilation system could be fitted in the application area and Procedures introduced to deal with any spillages that might occur. Workers could be provided with respiratory protective equipment and other personal protective

equipment such as overalls and gloves and Given instruction and training in the hazards associated with the process and the control measures to

provided, particularly in the use and fitting of the protective equipment and clothing. Additionally it would be necessary to provide adequate washing facilities and facilities for the storage

of clothing and to prohibit eating and drinking in the work area.

4

Construction workers regularly use cement. Several of the long-term workers and one of the new recruits have complained about red and sore skin on their hands.

(a) Explain the possible reasons for the symptoms they are experiencing. Marks:6 (b) Outline control measures that could be used to minimise these symptoms in this situation. Marks:4

ANS

(a) The symptoms suggest that the workers are suffering from dermatitis caused by a chronic or repeated exposure to an irritant or irritants. Cement is a known irritant which can cause allergic contact dermatitis through contact with a sensitizer - chromium compound impurities in the material-that produces an overreaction from the body’s immune system. Sensitization can occur on first contact such as with the new recruit or after some time in the case of the long term workers. The effect of contact with the irritant de-fats and degreases the skin and overcomes the skin’s own defense and repair systems. Friction and abrasion from general floor lying will not help the condition.

(b) The control measures that could be used to minimize the symptoms such as

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Using a non- cement based compound, for example, a polymeric compound;

Wearing gloves to protect the skin and minimizing contact by the use of hand tools; Providing washing facilities so that contaminants can be washed from the skin as soon as possible

with the hands dried thoroughly after washing; Using pre-work and after work moisturizing creams to replenish the natural oils in the skin; Giving information to the workers on the importance of carrying out their own skin inspections and

encouraging them to report any problems with their skin; and Arranging for supervisors to carry out regular skin inspections of the workers.

Jan, 2012 July, 2009

5 A contractor is hired to fit a noticeboard in a small meeting room in an office block. This task involves drilling through some asbestos insulating board. (a)Outline the diseases caused by exposure to asbestos including their health effects. (7) (b)Outline the issues the contractor should consider when assessing the risk of exposure to asbestos arising from this task. (5) (c)Outline control measures the contractor should take when carrying out this task. (8) (a), Four main asbestos-related diseases were

(Mesothelioma, asbestosis, diffuse pleural thickening and cancer of the bronchus), Together with their associated health effects, such as chest pain, breathing difficulties and spitting up blood.

(b), The risk assessment should consider a wide range of issues including

The type of asbestos, whether it was likely to become airborne (and in what concentration) and The steps needed to prevent or control exposure. These and others are nothing more than standard risk factors in any hazardous substance assessment.

Some misinterpreted this part of the question and instead provided a method statement or a list of controls rather than risk factors.

(c), Range of items from the hierarchy of control but often did not give sufficient detail for the marks available. Control measures would include:

Limiting numbers of people exposed (various methods to achieve this); Limiting contamination spread; limiting fibre emission at source (work methods) and Capturing fibres that did escape; and use of specific PPE.

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Decontamination and training were also relevant.

6 RRC – IB5 – LAQ3

Contractors have been engaged to carry out re-cabling work in an office. During this work a small area of ceiling board is removed. At this point the office manager raises a concern that the ceiling material may contain asbestos and office staff and the contractors working in the area may become exposed to asbestos. (a)Outline the steps that should be taken to deal with this immediate problem. (8) (b)Describe the features and principles of operation of the equipment that should be used to determine the airborne concentration of asbestos fibres. (8) (c)Suggest steps that could be taken to prevent a similar situation arising during any future work of this nature.(4) ANS (a) The steps that might be taken, on discovering that contractors may have disturbed a possible asbestos containing material (ACM), would be to:

Stop work immediately (assume it is asbestos). Keep everyone else out of the area (to remove people from potential exposure). If dust/debris is present on the clothing of the worker (or anyone else) make sure that the clothing is removed

and bagged and that the person washes/showers immediately (leaving the shower clean too). Inform the person in charge (e.g. site manager). Place warning signs in the area “possible asbestos contamination”. Arrange for a sample to be taken and sent for analysis to discover if it is asbestos.

If the results show it is not asbestos, then no further action is required. However if it is, then depending on the size of the job, a competent contractor will be needed for removal. (b) The airborne concentration of asbestos fibres is determined in the following manner. Using the MDHS 39/4 method, a measured volume of air from a controlled flow sampling pump is drawn through a membrane filter held in a cowl filter head. After sampling, the filter is mounted on a microscope slide and made transparent using solvent. The fibres in a measured area are counted under the microscope and the concentration of fibres per volume of air is calculated from the fibre count and the measured volume. (c) There would be a need to find out if there is asbestos on/in the premises, what state it is in and what to do about it (if anything) in a planned, systematic way. A risk assessment, as to whether asbestos is, or is liable to be, present in the premises, should be undertaken. It should take into account the condition of the asbestos and

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7 The guidance document HSG173 “Monitoring Strategies for Toxic Substances” advocates a three stage strategy for exposure monitoring consisting of an initial appraisal, a basic survey and a detailed survey.

(a) For EACH of these THREE stages explain the circumstances under which that type of monitoring would be appropriate and 5

(b) Outline the methods and equipment that could be used in the monitoring. (10) (c) Indicate how the data obtained from the monitoring could be used to determine the adequacy of the

current controls that may be in place. (5)

(a) / b An initial appraisal is suitable in all circumstances. It helps establish the need for, and extent of, any exposure monitoring. It helps you decide if you need more information, like actual monitoring data. Information is gathered on substances, activities, exposure frequency/duration, existing controls, applicable exposure limits.

Simple qualitative methods are all that is required, e.g. smoke tubes (which show air flows); smell (unreliable); dust lamp (makes fine dust visible and identifies leaks/emission sources). A basic survey is what you do if your initial appraisal is inconclusive and you need more information to help you decide; i.e. the extent of the risk is uncertain. You would also do a basic survey when there have been major changes since the last assessment (such as changes to a process, procedures, controls), or if you have planned an unusual operation, are commissioning a new operation or if a new occupational exposure limit is in force. The basic survey is more detailed than the initial appraisal and attempts to estimate employees’ personal exposure and the effectiveness of controls. In this case, you would focus on the staff most likely to be exposed and the worst-case scenarios (such as peak exposure times). You could then use relatively crude, semi-quantitative methods to estimate their “worst- case” personal exposure (stain tubes and photo-ionisation detectors) or measure it using more rigorous, quantitative methods (bubblers, absorption tubes, particulate sampling heads, etc. that need to be sent off to a laboratory). You can also measure things like face velocity (using hot wire anemometers, etc.) to check local exhaust ventilation (LEV) is performing to the required standard. The detailed survey is used for complex cases where the basic survey leaves you with some doubt that things are normally well controlled (or as well controlled as they should be!). For example, exposure between employees may be highly variable; you may be dealing with carcinogens, mutagens or respiratory sensitisers (where a higher standard applies); estimates from initial appraisal and basic surveys suggest you are working very close to the occupational exposure limit or you need more evidence/data to justify the expense of putting in extra controls. Monitoring techniques would be similar to those already used in initial appraisals and basic surveys but would be a more detailed

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look at exposure patterns and more extensive quantitative personal monitoring (larger numbers of samples at different times, etc.). You might even need to do some biological monitoring. c) Control would be considered adequate if principles of good practice were being applied, the occupational exposure limit was not being exceeded and for carcinogens, mutagens and respiratory sensitisers, exposure was reduced to the lowest level reasonably achievable. Your surveys give you semi-quantitative and quantitative estimates of personal exposure (such as 8 hour time weighted average (TWA)), which can be compared with occupational and biological exposure limits to identify if control is adequate. Measurements of controls such as LEV can establish if it is underperforming compared to design intent which, even though you may be below the occupational exposure limits, may therefore be inadequate if you are required to maintain your controls to the lowest level reasonably achievable.

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Element IB5: Biological agents

IB6: BIOLOGICAL AGENTS

1

RRC – IB6 – SAQ3

(a) Define the term ‘biological agent’. (2) (b) Give FOUR examples of diseases caused by biological agents at work, stating for EACH case the causation agent and an occupation particularly at risk. (8) (a) A biological agent is a micro-organism, or microscopically small agent of biological origin, such as; bacterium, virus, or fungus that may cause disease or infection in humans. Bacteria, fungi and viruses can all be biological agents, as can other similar types of biological material such as; cancer cells, DNA and single cell parasites. (b) Four diseases that are caused by biological agents in workplaces are: Legionnaire’s disease (Legionellosis) caused by the Legionella bacteria which can be contracted by people passing near to infected cooling towers (parts of air conditioning units). Weil’s disease (Leptospirosis) is caused by the bacteria Leptospira. This disease can be contracted from the urine of rats, so sewer workers, people who take part in water sports, excavations, etc. can be at risk. Acquired Immunodeficiency Syndrome (AIDS) caused by the fluids of infected individuals and is transmitted by direct body fluid transfer, so paramedics, doctors and nurses are likely to be at risk. Hepatitis B, a liver disease, caused by the Hepatitis B Virus (HBV) again transmitted by body fluid contact. Again doctors, nurses and ambulance teams, as well as firemen and refuse disposal operators, are at risk.

2 (a) Outline the typical signs and symptoms of Legionnaire’s disease. Marks:5 (b) Outline the conditions under which legionella bacteria may grow. Marks:3 (c) Outline the means of controlling the growth of legionella bacteria. Marks:12

(a) Signs and symptoms of Legionnaire’s disease include

Fever, chills, shivering, headache and muscle pain; dry cough and breathing difficulties; Diarrhea or vomiting; confusion and even delirium and Ultimately respiratory failure leading to death. The Incubation period for the disease is between two and ten days.

(b) Factors which may have contributed to the worker contracting the disease include

Inhaling airborne droplets of water containing viable legionella which proliferate in warm stagnant water and in environments containing organic material, sludge and algae which feed the bacteria;

Coming into contact with hot and cold water systems, water systems incorporating an

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evaporative condenser or wet air conditioning unit, humidifiers and air washers that create a spray of water droplets, spa baths and pools where water is deliberately agitated or with other systems that release sprays or aerosols during operation;

The worker’s age since the disease is more likely to be prevalent in those between 40 and 70; State of health since persons suffering from cancer, or kidney and chronic respiratory disease are at

higher risk and his lifestyle involving the use of tobacco and an excessive amount of alcohol. There was occasional confusion shown between Legionnaire’s and Weils disease with the suggestion that exposure to rats’ urine might have been a contributory factor.

(c) The initial action the company should take to minimise the risk of future outbreaks would be

To carry out a risk assessment to identify the potential sources of bacteria such as cooling towers, humidifiers and showers, the potential for water droplet and sludge formation, and

The persons at risk. Control measures would then involve regular disinfection of water systems with biocides; Inspection and cleaning of water storage tanks, covering them and using drift eliminators or

shields to prevent mists; Maintaining hot water storage temperatures at temperatures greater than 60 degrees C and

cold water below 20 degrees C; Regular inspection of water systems and clearing them of organic materials, sludge and algae; Maintaining a flow of water to prevent stagnation with static systems being flushed on a regular basis; Replacing wet air conditioning systems with dry air systems or ensuring their maintenance on a

regular basis; Undertaking regular monitoring of temperature and chlorine or biocide levels and periodically sending

water samples for analysis. While reference was made in answers to some of the above control measures, there was little mention

of the need to carry out an initial risk assessment.

3 An employee working for a large engineering company has recently been diagnosed with Legionnaire’s disease. Describe the content of a presentation that might be given to the workforce to inform them about the disease and the controls adopted by the company to address any concerns they may have. Marks:20

- An introduction how legionella is contracted, and the conditions the bacteria can be found in and proliferates. - Typical symptom of legionella such as fever, chills, shivering headache, diareiah and vomiting - The major at risk groups – prevelance among 40-70 years age group, smokers, alcoholics and persons with

cancer

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- Measures that company could take to prevent and control the legionella would be to – Undertake risk assessment to identify potential sources And those at risk Routine testing of the water system Treating water system with bactericides Maintaining water temperature between 20 c or above 65 c, Ensuring water systems are cleared of organic materials and Keeping water tank covered

4

RRC – IB6 – LAQ2

(a) Explain how the hepatitis B virus may be transmitted to workers AND identify the types of occupation where workers may be at risk of infection. Marks:5 (b) Outline control measures to minimise the risk of hepatitis B infection. Marks:15 The virus might be transmitted through direct contact with infected blood or body fluids arising from infected instruments such as needles and may spread through broken or damaged skin. Additionally there is the possibility that the virus may be transmitted by splashes of infected blood or other body fluids to the eyes, nose and mouth. The examples given of occupations at risk should have included amongst others healthcare workers and those involved in the provision of social care and also those involved in refuse collection or cleaning services. This part of the question was competently answered by most candidates though there was a suggestion made that the disease might be contracted from animals and that therefore abattoir workers could be at risk. Control measures to minimise the risk of hepatitis B infection:

The use of litter picking sticks to minimise the risk of puncture wounds; The prohibition of eating and drinking where there is a risk of contamination; The use of PPE such as goggles, gloves and footwear; covering up wounds with a waterproof

dressing; The safe disposal of sharps; The introduction of procedures for the collection and disposal of contaminated waste and for

cleaning up body fluids and blood and the importance of frequent hand washing. In addition to the practical elements of a safe system of work, other measures such as

The Consideration of an immunization programme for particularly vulnerable workers; The introduction of clear procedures for actions to be taken in response to a needle stick or similar

type of injury such as the encouraging of bleeding, rinsing under warm water and seeking prompt medical advice and

The provision of information on hepatitis and training in systems of work to high risk and other workers and

July, 2010

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The importance of ensuring that special precautions are taken by first-aid personnel such as the use of mouth shields.

There was a suggestion that a programme of health surveillance should be introduced for those workers who were at risk.

5

RRC – IB6 - SAQ2

The risk of contracting Weil’s Disease (Leptospirosis) is a concern to windsurfers at a local water sports centre. Provide advice to these windsurfers which outlines: (a) The ill-health effects associated with this disease. (2) (b) Why windsurfers might be at risk. (2) (c) Practical steps that instructors can take to minimise the risks to themselves. (6)

(a) Leptospirosis is a bacterial infection of the blood (initially) which results in flu-like symptoms in the first instance (headache, fatigue, fever).

It can lead to more severe effects in some cases; Abdominal pain, jaundice and liver damage as the bacteria move out of the blood and invade

internal organs. It can be fatal if left untreated.

(b) The causative bacteria (Leptospira genus) are carried by rats (and other rodents) which continuously

urinate and live close to water. The bacteria is carried out of the rat in urine and so may find its way directly into water where it can survive longer than if allowed to dry out. If a windsurfer touches contaminated water, or wet urine, then they pick up the bacteria which can then enter the body through cuts and grazes, and through the nose and mouth.

(c) Practical steps that might be taken by windsurfing instructors to minimise the risk of infection would

include: Staying out of the water when instructing (supervising training from land or from boat). Good personal hygiene practices such as showering after immersion in water and always washing hands

before eating. Avoiding swallowing the potentially contaminated water. Washing hands thoroughly before eating Protecting the skin against water contact by wearing protective footwear, wet suit and covering existing

cuts/abrasions with waterproof plasters. Disinfecting cuts received whilst in the water before dressing the wound. Seeking medical assistance in cases of illness and informing doctor about occupation/carrying card. Looking for the sign of rat infestation and applying appropriate pest control methods.

3. Jan 2008

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5 (a) Outline the health effects associated with the human immunodeficiency virus (HIV). Marks:3 (b) Outline control measures to protect against occupational exposure to the virus. Marks:7

(a) HIV is a virus which attacks the body’s immune defence mechanism, weakens an individual’s ability to fight infections and may cause AIDS. It affects appetite, inducing the AIDS wasting syndrome, and may lead to a risk of opportunistic infections such as hepatitis B, TB or thrush. b. The control measures include to protect against occupational exposure to the virus such as

Pre-employment medical screening and the identification and protection of high risk workers; Procedures for handling sharps and for dealing with spillages and the provision of an adequate disposal

facility both for sharps and waste; The provision of micro-biological cabinets for handling samples; The cleaning and disinfection of surfaces; The provision of suitable personal protective equipment such as overalls, gloves and masks; Ensuring that workers are given a high level of supervision together with adequate instruction and

information on the risks involved and the precautions to be taken including the need for a high level of personal hygiene;

Introducing procedures for dealing with possible bodily contact from violent patients and ensuring that adequate facilities are provided for working outside controlled environments such as in a patient’s home.

Jan, 2011 JULY 2013

6 According to current veterinary and medical opinion the bacterium E. coli O157 should be assumed to be carried by all ruminants (cattle, sheep, goats and deer). In addition, this bacterium can exist for long periods of time outside of the animal (in soil and faces).

(a) Identify ways in which school children visiting a farm might be exposed to E. coli O157 bacterium. Marks:4 (b) Explain a range of practical control measures that should be put in place in order to reduce this risk of

exposure. Marks:6 ANS

(a) The bacterium was transmissible through hand to mouth contact. Such as touching animals and contaminated surfaces, which could then be transferred to the mouth when eating.

(b) There was a range of control measures that could be put in place.

One of the most important is handwashing (ensuring facilities are provided in specific locations and that children wash their hands properly, especially before eating).

Providing advice on precautions to schools prior to the visit would be a good idea to make sure children are briefed before arrival.

Supervision and signs around the farm would reinforce this message. Other measures would include

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cleaning and disinfection and segregation of eating areas.

7

3 RRC – IB6 – SAQ1

A research laboratory undertakes necessary work with biological agents. These biological agents are categorised as extremely hazardous, being placed in the highest hazard group. Outline a range of technical controls that should be used to minimise the risks to those working in the laboratory, where elimination or substitution of the hazard is not possible. Marks:10 or Outline the means of controlling exposure to biological agents in a pathology laboratory. (10) The methods of controlling exposure to biological agents in a pathology lab would include: Limiting the number of employees exposed and restricting access to authorised persons only by the use of security measures.

Minimising the potential for release of biological agents; through task design and engineering controls. Displaying biohazard signs at lab entrances and on storage units. Preparing emergency plans to deal with accidental release, spillage and worker contamination. Decontamination and disinfection regimes and procedures that would be carried out both routinely and in the

event of accidental releases. Constructing rooms and surfaces for ease of cleaning. Ensuring the safe collection, storage and disposal of waste; including sharps bins for all needles and incinerator

disposal for all clinical and biohazard waste. Safe handling and transport of samples, where necessary within containment. Appropriate personal protective equipment; such as gloves, coats, overalls, eye protection and respiratory

protective equipment. Vaccination programmes where appropriate and health surveillance. Hygiene measures; such as washing facilities and the prohibition of eating, smoking and drinking in the

laboratory. An appropriate containment level assigned to the laboratory and adherence to the criteria implied (a minimum

of containment level 2). Competent and trained personnel.

Jan, 2012

8 A research laboratory undertakes intentional work with biological agents such as Ebola and Lassa viruses.These biological agents are categorised as extremely hazardous, being placed in the highest hazard group. Outline a range of technical controls that should be used to minimise the risks to those working in the laboratory, where elimination or substitution of the hazard is not possible. Marks:10

Jan, 2009

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9 (a) The risk of contracting Leptospirosis is a concern to users of a local water sports centre. Provide advice to these users which outlines: not in syllabus

(i) The ill-health effects associated with this disease; Marks:2 (i) Why users might be at risk. Marks:2

(b) Outline the practical steps that the centre’s instructors can take to minimise the risks to themselves.

Marks:6

Jan, 2008

10 (a) Outline what is meant by the term ‘biological monitoring’ AND give examples where such monitoring may be appropriate. Marks:6

(b) Outline the practical difficulties that an employer must overcome when introducing a programme of biological monitoring. Marks:4 (a) Biological monitoring is concerned with the measurement or assessment of hazardous substances or their metabolites in tissues, secretions, excreta or expired air. It is complementary technique to air monitoring or sampling and can be used to determine if existing controls are adequate; when information is required on the accumulated dose in a target organ; when there is a specified guidance value against which a comparison might be made (such as in EH 40); when there is significant absorption by non-respiratory routes; in circumstances when there is significant reliance on personal protective equipment and where the monitoring is required by law. (b) Concerning the practical difficulties an employer should take into account when introducing a programme of biological monitoring. Apart from the monitoring required by statute, it would normally be conducted on a voluntary basis. Consequently the informed consent of those involved would have to be obtained and their concerns overcome. Other difficulties include the availability of suitable facilities or a location to carry out the monitoring especially if this has to be done at the end of the shift; the availability of specialists to carry out the monitoring for example if blood samples are to be taken; maintaining the integrity of samples to avoid cross contamination and ensuring there was no possibility of cross infection; maintaining the confidentiality of the individual; the cost involved in carrying out the exercise; and finally the fact that there are few guidance values available for comparison – a point that was absent in many answers..

Q6. July 2012 Jan, 2010 July, 2008

11 (a) Describe the difference between workplace atmospheric monitoring and biological monitoring of an individual’s exposure to toxic substances. Marks:4

(b) Compare and contrast the use of atmospheric and biological monitoring in the control of exposure to toxic substances. Make reference to the role of relevant benchmark standards and exposure limits in your answer. Marks:16

July, 2009 July, 2007

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Element IB6: Physical agents 1 – noise and vibration

IB7: PHYSICAL AGENTS 1 – NOISE AND VIBRATION

1 Workers driving vehicles on a construction site may experience whole- body vibration (WBV). (a) Explain the meaning of WBV. Marks:2

(b) Outline the health effects of WBV. Marks:2

(c) Outline measures the drivers could take in order to reduce the effects of WBV. Marks:6

(a) The meaning of whole body vibration is shaking, jolting or vibration of the human body due to transmission to the worker through a contacting or supporting structure such as a seat or the floor which itself is vibrating. (b) The health effects of WBV include

Fatigue and insomnia, Headache, shakiness shortly after and/or during exposure, Stomach problems such as motion sickness and muscular or back disorders.

(d) Measures that drivers could take in order to reduce the effects of WBV include Following worksite routes to avoid driving over rough ground and avoiding driving over holes or loose

material to reduce bumping and jolting; Adjusting vehicle speed to suit ground conditions and operating it smoothly without sharp or sudden gear

changes or braking; Adjusting the seat suspension to suit their individual weight and to avoid “bottoming out”; Adjusting seat position to make hand and foot controls easier to operate; Taking regular breaks away from the machine and undertaking relevant daily vehicle checks, particularly of tyre

pressures.

July, 2011

2 Bulldozer drivers at a large construction site have reported back pain which they believe is caused by exposure to whole body vibration (WBV).

(a) Outline a range of control measures that could be used to minimise the risk of the drivers experiencing back pain caused by exposure to whole body vibration. Marks:7

(b) Identify THREE other possible work-related causes of the back pain being experienced by the bulldozer drivers. Marks:3

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(a) Control measures include

Selecting a vehicle with the size, power and capacity best suited for the terrain and task; Ensuring that an individual’s exposure to whole body vibration (WBV) is kept below the recommended

threshold; organising traffic routes used by vehicles to avoid rough and uneven surfaces wherever possible and maintaining both the site roadways and the vehicles’ suspension;

Fitting suspension seats with vibration damping characteristics and adjusting these to suit the weight of individual drivers to avoid “bottoming out”;

Organising work patterns including job rotation to ensure that drivers have breaks away from the vehicle and

Advising them on how to minimise exposure to whole body vibration by avoiding jolts and shocks.

(b) The other possible work related causes for the back pain include Poor posture; Sitting for long periods of time; The poor layout of controls requiring the driver to stretch and twist to reach a particular control or to

obtain good vision; No method provided for adjusting the seat which could make hand and foot controls difficult to

operate; The repeated climbing into and jumping down from a high cab and carrying out other

construction related activities such as the manual handling of heavy loads.

3

RRC – IB7 – LAQ3

A newspaper printing company that employs 80 workers operates several printing presses in a large open-plan area. Noise is considered to be a problem.

(a) Identify the information that should be obtained before undertaking a noise survey in the open-plan area. Marks:6

(b) Explain how the noise survey should be undertaken and the type of equipment that could be used to assess workers’ noise exposures. Marks:14

Answer: (a) The information needs to be obtained include

Before undertaking a survey of the print shop, a visit to the work area would be advisable in order to determine if there is a noise problem; if you cannot hear normal speech at a distance of two metres, then there is.

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Persons who are at risk and, in particular, any individual susceptibility to noise (for example pre-existing noise induced hearing loss).

The duration of worker exposure to the noise would be another factor; this might be determined by work patterns and shift patterns and might mean that certain groups of workers were not at risk whilst others might be.

The site layout and the location of the machines; The identification of noisy machines, processes, operation times, and Manufacturer’s data of all noisy

machines; The number and location of machine operators; A review of previous surveys; An assessment of existing controls; Legal requirements and legal limits; A review of existing audiometry records, any previous complaints and a review of maintenance

records to identify problem machinery.

(b) A suitable framework could be based upon a basic survey, followed by a more detailed survey. Discussion of measurement equipment, frequency analysis and personal noise exposure monitoring would

also be of relevance. Before the survey is started, there should be consultation with the workforce, a competent assessor

should be appointed, The equipment to be used should be calibrated before and after measurements have been taken, and

results used to plot a noise map on a plan of the printing area. A basic survey would involve the use of a simple sound level meter for spot checks as well as integrating

sound level meters. Measurement of noise levels at planned points around the factory would enable identification of areas

where noise exposure is at or above action levels and a record should be made of what machinery was operational at the time the readings were made.

The detailed survey would involve the use of integrating sound level meters; o A selection of appropriate sample times over which to measure Leq; o The measurement of noise levels at operator positions averaged over typical time periods and the

use of a calculation method or a sonogram to determine exposure. o The survey should include the measurement of peak noise levels and results would be plotted on a

noise map. The frequency analysis is useful for deciding on noise control measures such as the provision of enclosures

for example and the selection of hearing protection and should have formed part of the survey. Representative personal noise exposures should be measured for a sample of operators and peripatetic

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workers, using dosimeters or microphones close to the ear. These noise measurements, combined with exposure duration, enable daily (or weekly) equivalent

personal exposure to be estimated for these workers.

4

RRC – IB – 7 – LAQ

1

(a)Identify the different types of equipment that can be used in the measurement of noise in the workplace and comment on their respective features and roles in assessing worker exposure to noise. (12) (b)Review the benefits and limitations of audiometry as part of a hearing conservation programme. (8) ANS (a)Basic sound level meter – for spot checks. A simple sound level meter which would be capable of measuring sound pressure level on the A- weighting and C-weighting matrices. With analogue or digital readout. Useful for carrying out spot checks and initial surveys to spot problems, but not very useful for detailed surveys. Integrating sound level meter – for integrating exposure to noise over the exposure period; A-weighting mode; equivalent daily noise exposure calculated from these measurements (and duration of exposure); peak action level; used to make noise measurements for purposes of noise regulations (must be at least Class 2 or Type 2). Octave band integrating sound level meter (or ISLM with an octave band attachment) – important for analysis of sound for choosing ear protection and designing noise abatement controls. This type of meter can give the noise contributions at various frequency bands across the human hearing spectrum. Dosimeters – personal noise exposure over working day; worn by worker, often data downloaded wirelessly. This meter is usually small and portable and may not have any form of read-out for the wearer to look at. Useful for assessing the exposure in workrooms where workers move around a lot, or fluctuating noise levels make ISLM use difficult. All must be calibrated and therefore a calibrator is essential. (b) The benefits of audiometry (Measuring sensitivity of hearing)are:

Pre-employment baseline testing for new or prospective employees. Identification of early signs of noise induced hearing loss so as to be able to remove affected workers from

high noise areas. Monitoring the effectiveness of any hearing conservation programme on the basis that if the programme is

working, then audiometry will show no significant NIHL (noise-induced hearing loss) cases. The limitations of audiometry are:

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Making sure operators are not exposed to high noise levels prior to test (causes Temporary Threshold Shift which skews the results).

It is an inherently reactive technique – the damage has already been done. The results of audiometry may be used to support claims of noise induced hearing loss.

5 A motorcycle courier is exposed to high levels of noise and vibration as he rides his motorcycle. The vibration originates in the engine and wheels and is transmitted to the rider through the vehicle seat, handlebars and foot pegs. The high noise level arises mainly from wind turbulence around the rider’s crash helmet. (a) Outline the ill-health symptoms related to noise and vibration that the rider is likely to experience from prolonged

and repeated riding. Marks:4 (b) Outline how you might assess:

(i) The noise level experienced by the rider; Marks:4 (ii) The level of vibration experienced by the rider. Marks:4

(c) OUTLINE the range of practical measures that can be taken to reduce the risk of ill-health effects to the driver.

Marks:8 ANS

(a) The ill-health symptoms related to the noise include Induced hearing loss, Permanent threshold shift, Permanent loss of hearing and tinnitus.

As for vibration, these would include

Tingling, Pins and needles, Pain in the hands and wrists, Reduced dexterity and sensitivity in the hands, Blanching of fingers and Backache caused by jarring.

(b) (i)An assessment of the noise level experienced by the rider could be made by the use of a miniature

microphone or probe forming part of a calibrated instrument within the helmet and placed near to the

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rider’s ear canal. This would enable measurements to be made which would need to be representative taking account of the riding style, the roads and the exposure time. Octave band analysis would indicate the frequency make up of the noise. The initial noise measurements would be converted to an equivalent ‘undisturbed field’ value (as if the rider’s head was not there) and the 8 hour A-weighted equivalent calculated. A comparison might then be made with standards and exposure limits. (ii)As for the level of vibration experienced by the rider, this should be measured at the interface between the body and vibrating surfaces such as the handle bar grips and seat, using an accelerometer which measures acceleration in 3 orthogonal dimensions, with measurements being taken over different riding conditions. The level and duration of exposure would be recorded and compared with the exposure limits for hand-arm vibration and those for whole body vibration.

(c) The practical measures include

Providing the rider with a helmet of more aerodynamic design modified to reduce turbulence and ear plugs selected for their correct attenuation characteristics;

Fitting a wind shield and mounting foot pegs on vibration damped mountings, and Checking the wheel balance and pressure of the tyres; Adjusting the suspension and replacing the seat with one with better damping properties; Modifying or replacing the handle bars to reduce the transmission of vibration and replacing the handle

bar grips with others with better vibration damping; Using rubber mounts for the engine and checking the tightness of the mounting bolts; Making sure that the engine is properly maintained and tuned; Providing warm gloves and clothing for the rider to maintain circulation and reducing the duration of

his exposure by route planning and job rotation. Instructions to the rider (such as not to grip the handlebars too tightly) will also help reduce vibration

transmission

6 A small printing company operates a number of printing machines which are located in an open-plan workshop. Following a noise survey, the company discovers that their workers are being exposed to high average daily noise levels. The noise levels exceed regulatory exposure limits.

(a) Describe the acute and chronic physiological effects of exposure to high noise levels on the individual. Marks:4

(b) Explain what steps the company should take to protect workers. Marks:16

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In your answer clearly explain the range of technical and organisational control measures that could be introduced.

(a) The effects by high exposure noise levels include Tinnitus, A ringing sound in the ears that may be chronic or acute; Threshold shift which can again be temporary or permanent; and Noise induced hearing loss where those affected suffer a loss of sensitivity to sounds in the speech

range.

(b) The steps to be taken to protect workers include

The technical controls by replacing older/noisier equipment with machines that emitted lower levels of

noise; Isolating the noisier machines in a separate area of the workshop and building a noise enclosure of

suitable noise attenuating material around them; Mounting the noisy equipment on rubber strips or dampers; Lining the walls and floor of the workshop with acoustically absorbing material and applying

damping to metal panels on machines; and Creating a noise haven for the employees. If, even after taking the above measures, the provision of hearing protection was found to be

necessary, it should be chosen based on an octave band analysis measurement of the noise emitted in order to provide the best overall reduction in exposure.

Organizational controls include

Reducing exposure times by job rotation; Designating hearing protection zones; Providing training to employees on the risks associated with exposure to noise and on the fitting and

maintenance of hearing protection; Ensuring hearing protectors, once issued, were used and introducing disciplinary procedures to deal

with those employees who did not wear them

7

RRC – IB – 7 – SAQ

(a) Identify the risk factors associated with hand-arm vibration syndrome (HAVS). (4) (b) Outline a strategy for assessing the risk of HAVS amongst workers exposed to vibrating equipment. (6)

(a) The risk factors associated with hand-arm vibration syndrome include:

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1

Actual exposure to vibration, The magnitude of that exposure, The direction of the vibration put into the hand, The frequency range of the vibration, The duration of exposure (i.e. The length of time that an individual worker actually spends with their

hands on the handles of the vibrating equipment with the equipment working), The need to use force to grip tools, Any exposure to cold and wet conditions, Any pre- existing circulatory problems (perhaps caused by previous exposures to vibration, or as a

result of other conditions such as reynaud’s phenomenon).

(b) A strategy for assessing the risks of HAVS amongst workers exposed to vibrating equipment would require, In the first instance, that all of the equipment held in the hand with significant vibration magnitude

should be identified. The workers at risk, i.e. the workers who actually use the identified hand-held vibrating equipment,

must be identified. These workers’ exposure to vibration must then be reliably estimated by assessing the magnitude of

risk (looking at tasks being performed, vibration frequency, duration of use, work methods, etc.). This estimation might make use of manufacturer’s data, but it may also require physical measurement

of vibration magnitude using accelerometers. These estimated vibration doses must then be compared to exposure limits. For any employees identified to have an exposure at or above the relevant exposure limit health

surveillance may be necessary and exposure reduced below the limit.

8

Hand-Arm Vibration Syndrome (HAVS) can be caused by frequent and prolonged use of hand-held power tools. (a) Identify the signs and symptoms of Hand-Arm Vibration Syndrome. (2) (b) Outline a range of control measures that could be used to minimise the risks to workers of developing HAVS when using such power tools. (8) Answer :-

(a) Symptoms of Hand-Arm Vibration Syndrome include: Loss of feeling,

Q5. JULY 2012

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Numbness, Tingling and loss of dexterity in the tips of the fingers; Blanching (white finger); An increase in the severity of the symptoms during cold weather and the progressive nature of the

condition, affecting more fingers or parts of fingers and leading possibly to gangrene.

(b) Organisational and technical control measures relevant to the use of hand-held power tools and presented them in an appropriate hierarchy. Technical control measures would start with

The consideration of alternative work methods to eliminate the task, but if this was not practicable, to automating or mechanising the work;

Avoiding tools that are too small and not powerful enough since these prolong the task and of course the exposure;

Replacing the equipment with a lower vibration model and introducing a system of regular maintenance to ensure vibration was kept to its designed level.

Organisational control measures would include

Ensuring the organisation’s purchasing policy takes account of vibration emissions (as well as other requirements);

Changing workstation design to minimise loads on hands, wrists and arms, for instance by the use of jigs or suspension systems to grip heavy tools;

Planning work schedules to limit time of exposure to vibration; Providing warm clothing and a warm environment to encourage good blood circulation; Referring those experiencing early symptoms to the occupational health department and having a

health surveillance programme in place and Finally ensuring that workers receive adequate information and training on the risks associated with

the process, the symptoms of the syndrome and the control measures that should be followed.

9 The figure below shows an audiogram for an adult worker. Q4. July 2012 July, 2009

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(a) Explain what is meant by ‘threshold shift’. Marks:2 (b) Outline the significance of the shape of the audiogram. Marks:2 (c) Outline the benefits AND limitations of audiometry as part of a hearing conservation programme. Marks:6

Part (a) Temporary Threshold Shift (TTS) Exposure to a high noise level; hearing acuity returns with time. (Caused by fatigue of the hair cells in the cochlea.) A dip in hearing acuity occurs at 4,000 Hz. Permanent Threshold Shift (PTS) A non-reversible condition; usually follows from continual TTS exposure. For part (b), there was a tendency to describe the shape of the graph rather than identify its significance. 4 KHz notch is typical of noise-induced hearing loss. For part (c), Short / or The benefits of audiometry include:

Evidence of effectiveness of hearing conservation programme.

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Pre-employment identification of pre-existing problems. Identification of early signs of noise induced hearing loss. Basis to defend claims of noise induced hearing loss.

Limitations of audiometry include: Not preventative. Information may precipitate claims. Possible inaccuracies in data. Doesn't identify source of noise induced hearing loss.

10 A noise assessment carried out at a manufacturing plant has revealed that personnel, working in the vicinity of machinery, are exposed to noise levels in excess of acceptable limits. It has been decided to investigate engineering methods of reducing noise exposures. Explain the purpose and design features of:

(a) an acoustic enclosure: Marks:10

(b) an acoustic haven : Marks:10

(c) Hearing protection may also be required to further reduce exposure to the noise, OUTLINE factors should be considered when selecting hearing protection. 6

Q10 Jan 2013 (a)

July, 2007

Q10 Jan 2013 (b)

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Element IB7: Physical agents 2 – Radiation

IB8: PHYSICAL AGENTS 2 – RADIATION AND THERMAL ENVIRONMENT

IB7.1 Outline the nature of the different types of ionising and non-ionising radiation IB7.2 Explain the effects of exposure to non-ionising radiation, its assessment and control, including for the special case of optical lasers IB7.3 Explain the effects of exposure to ionising radiation, its measurement and control.

1 (a) Identify FIVE workplace sources of ionising radiation. Marks:5

(b) Outline control measures that should be in place when persons may be exposed to ionising radiation at work. Marks:15 Describe the possible health effects from exposure to ionizing radiation: Marks:5 (July, 2010)

(a), Sources such as

The use of nondestructive testing (NDT) equipment; The medical/dental use of x-rays; Re-processing nuclear fuels and the presence of radio-active isotopes in nuclear power stations; The presence of ionising radiation albeit in small quantities for instance in smoke detectors and luminous

articles; and The use of ionising radiation for process measurement and control and in laboratories for research projects.

Jan, 2012

Jan, 2010 July, 2010 July, 2008

1

RRC – IB 8 – SAQ2

(a) Identify THREE different workplace situations where ionising radiation may be encountered AND state the source of the radiation. Marks:3

(b) Describe the possible health effects from exposure to ionising radiation. Marks:5

(c) Outline the control measures that should be in place when persons may be exposed to ionising radiation at work. Marks:12

(a) (b) The possible health effects from exposure to ionising radiation will include (5)

Radiation sickness (nausea, vomiting, and hair loss), Dermatitis, Burns either superficially to the skin or more penetrating burns causing cell damage, Cataracts, Temporary or permanent infertility, Decreased immunity and cancer induction.

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Radiation sickness and decreased immunity were scarcely mentioned. Or Long The possible health effects from exposure to ionising radiation depend on timescale and can be categorised as acute, chronic and genetic. Acute effects include reddening of the skin (erythema) skin burns, or on a milder scale, dermatitis. Radiation sickness results from cell death in the GI tract and hair loss is also a symptom. Changes to DNA may occur which may lead to cancer or hereditary damage. There is also likely to be decreased immunity which makes it more difficult to recover from acute exposure. Chronic effects include cataracts resulting from radiation exposure to the eye, cancer induction with a long latency period, and possible sterility. Genetic effects affect future generations and may result in hereditary damage and harm to the unborn foetus. (c) Control measures that should be in place where persons may be exposed to ionising radiation at work include –

Limiting the time of exposure with the exclusion of particularly vulnerable groups such as young persons and pregnant women;

The use of sealed sources whenever possible; Increasing the distance between the radiation source and those at risk to reduce the level of exposure; Using shielding between the radiation source and those likely to be exposed with the amount of shielding

required dependent on the energy of the source; Containment for example by the use of glove boxes; Prohibiting eating and drinking in areas where unsealed radioactive sources are used together with the need

for a high standard of personal hygiene to prevent spread and The covering of all breaks in the skin with protective material; The provision, use and, where applicable, laundering of personal protective equipment such as gloves, lab

coats and over shoes; the availability of competent advice; The provision of training and information to workers on the health risks involved and the control measures to

be applied; Personal monitoring by means of film badges; Regular monitoring of the work area for example by means of a geiger counter and ensuring the safe disposal

of all contaminated materials.

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2 (a) Identify the way in which lasers are classified according to their hazard. Marks:2

(b) Low power lasers are widely used to read bar-code labeled products at checkouts in retail premises. Outline:

(i) the design features; Marks:4 (ii) the procedural controls: Marks:4

that should be in place for the safe operation and maintenance of the equipment. or (a) Identify the way in which lasers are classified according to their hazard. Marks:6 (b) Low power lasers are widely used to read bar-code labeled products at checkouts in retail premises. Outline the design features that should be incorporated into these laser products to ensure their safe operation and maintenance. Marks:4 (a) The classification of lasers is defined in an IEC standard - IEC 60825 (also EN 60825). The classifications are based on accessible emission levels with the power of the lasers measured in milli watts (mW). There are seven different classifications - 1, 1M, 2, 2M, 3B, 3R, and 4 and marks were awarded to those who additionally identified the graduation in the level of hazard associated with each class from Class 1 - the lowest level to Class 4 lasers which pose the greatest hazard. (b) The design features that should be incorporated into the laser products to ensure their safe operation and maintenance include the laser having no greater power than Class 1; the use of embedded systems; the fitting of a protective housing with trigger operation on the hand held version; incorporating a key control with interlock to the power source; the provision of signage and the appropriate positioning of the laser, including hand-held equipment, to avoid eye-level exposure.

Jan, 2011 JUL 2013

Jan, 2009

3

RRC – IB 8 – SAQ1

Outline the precautions needed to prevent accidental exposure to a high power laser used for cutting metals. (10)

Prior to the use of the laser a risk assessment, focusing on the risks associated with the use of a class 4 laser, would be necessary, as would the development of a safe system of work on the safe use of the laser.

The room or area that the laser was in would have to be designated a Laser Protection Area and appropriate warning notices should be displayed.

One of the most important precautions that would be taken, to prevent accidental exposure to a high powered laser used for cutting metal, would be the total enclosure of the laser, the beam and the metal item being cut. This would be achieved by the use of metal enclosures (guards) around the machine and its workbench.

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Any openings into the enclosure, such as access doors, material feed hatches, etc. should be interlocked in such away that electrical power is isolated from the laser itself until the guards are in place. In some instances this total enclosure is possible.

In other instances it is not and then partial enclosure of as much of the laser and work area as possible must be achieved using fixed and interlocked guards.

Access to the laser must be restricted to authorised personnel with suitable training to understand the risks and precautions of the device.

Eye protection would have to be worn in the vicinity of the laser to prevent damage from UV radiation emitted by the cutting process.

With a high powered laser, there is also the risk of reflected laser light scattering off rough dark surfaces, so the eye protection should totally enclose the eye so as to protect against this laser scatter.

Warning signs should be displayed during the actual operation of the laser, perhaps with a visible warning at the same time.

Training for operators and their supervisors would have to be given on the various risks inherent with the device and the precautions necessary to ensure safety

4

RRC – IB 8 – SAQ1

An organisation that provides sports facilities for employees and their families is about to install ultra-violet sunbeds and lamps. Identify the risks associated with the use of such tanning equipment and the precautions that should be taken. (10)

The risks associated with the UV radiation given off by the tanning equipment are: UV rays video

Skin cancer or melanoma, which can prove fatal. Burns to the skin (same condition as sun-burn). Eye damage such as cataracts or conjunctivitis. Weakened immune system. Premature aging of the skin, due to breakdown of the elastic collagen in the skin. Photosensitization whereby other chemicals in the body are activated by the UV to produce skin irritation and

pigment changes. The precautions that would be appropriate would include:

Physical screening of tanning equipment to prevent non-users from any exposure to the UV light. Provision and enforcement of the use of goggles to protect the eyes. Training for all staff in the use of equipment, safety controls and the importance of exposure times.

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Having safety features, such as timers and emergency alarms, fitted to the equipment to prevent overexposure from occurring.

Maintenance of the equipment with special attention given to the correct types of UV tubes fitted to the tanning equipment.

Information and advice to users on the need to limit or avoid exposure, especially for high risk individuals such as those with fair skin.

5

A new leisure centre is planning to install ultra-violet (UV) tanning equipment. The equipment uses UV sources with a higher intensity than normal sunlight to accelerate tanning.

(a) Outline control measures that should be put in place for BOTH workers and customers for the safe operation of this facility. Marks:12

(b) Identify BOTH the acute and chronic effects that could result from exposure to UV radiation. Marks:4

(c) Outline TWO other examples of occupational exposure to UV radiation. Marks:4

ANS (a) Control measures that should be put in place both for workers and customers would initially taking into

account The customer’s risk factors such as skin type, medication, age, pregnancy and family skin cancer

history and recommending and restricting their time of exposure. Workers would need to be made aware of the risks of exposure to UV radiation and then instructed in

the operation of the equipment including the safety controls and features fitted such as the timer and emergency alarm and the importance of carrying out pre-user checks and cleaning between each customer.

Dealing with the customers would also be important and workers would need to advise them on the risks associated with UV exposure,

The recommended duration/frequency of their exposure and the precautions to be taken such as wearing goggles and sun screen products.

Other control measures that should be put in place include o The screening or enclosure of the tanning equipment, o The siting of worker workstations away from stray UV radiation, o The provision of suitable goggles and ensuring their use, o Carrying out regular maintenance on the equipment such as changing tubes,

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o Maintaining records of customer exposure and displaying safety advice to customers.

(b) The acute effects that could arise from exposure to UV radiation are erythema or sun burn and eye irritation or arc eye. The chronic effects could well be premature skin ageing, cataracts and skin cancer.

(c) The examples of occupational exposure to UV radiation include

Construction or agricultural workers from exposure to the sun; Welders undertaking arc welding; dentists using uv light sources for dental treatments; Laboratory workers using uv light sources to sterilize equipment; Workers undertaking research using high powered lasers and printers using uv radiation to cure inks

and lacquers.

6 RRC – IB 8 – LAQ2

A research company is proposing to use small amounts of unsealed radioactive chemicals to act as tracers in the monitoring of the uptake and progress of chemical substances in micro-organisms. Describe the key risk control measures that should be considered with respect to the risk from radiation. (20)

A risk assessment would be necessary, undertaken by a competent person appointed by the employer (the research company). This competent person might be a Radiation Protection Adviser (RPA) or they might be a person with sufficient knowledge, training and experience of this sort of work to be considered competent in their own right. However, they would still work under the scrutiny of an RPA.

The design and specification of the laboratory where the experiments would be carried out would have to

be considered. o Floors and workbenches would have to be of a non-absorbent nature and easy to clean in the event

of accidental spillage or contamination. o Suitable lockable storage facilities would have to be provided. This would have to be clearly signed as

containing radioactive sources. o Containment facilities would have to be provided for the handling of the radioactive sources during

experimentation. This might be in the form of fume cupboards (partial enclosures with extraction) to prevent any vapour, mists or aerosols formed during handling from escaping into the laboratory air environment.

o Total enclosure might be necessary in some instances.

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Other containment might also have to be provided, for example incubators for growing up the micro-organism once the radioactive source has been added. These would have to be appropriately labelled so as to indicate the radioactive nature of the experiments being carried out.

The laboratory would have to be suitably designated, signed and kept secure against unauthorised access. If significant doses of radiation are anticipated, then the laboratory might have to be classed as a Controlled

Area. If doses are anticipated to be lower, then it might be classed as a Supervised Area. In either case, a set of procedures and rules would have to be developed to govern the radiation risk in the lab. This might be done by a designated Radiation Protection Supervisor (RPS) under the control of the RPA. The RPS would be responsible for the day to day running of the radiation protection controls.

Handling of radioactive sources would always be done whilst wearing lab gloves, might be done using forceps to maximise finger distance from source and might, in some instances, be done remotely using manipulators.

Workers within the lab might have to be designated as Classified Workers. Dosimetry would have to be carried out for workers in the lab in order to ensure that relevant dose limits

were not exceeded. Dosimetry would usually be carried out using dose badges, worn on the lab coats (or fingers) of workers.

These badges are then collected and analysed by an accredited service routinely to give a reliable estimate of exposure.

This dosimetry would be organised by the RPS. Radiation detection equipment, such as a Geiger counter, would also be present in the lab as would spill and decontamination equipment.

Arrangements would have to be made for the safe storage and disposal of waste materials. General good hygiene rules would apply in the lab, such as no eating, drinking (or smoking) and the

requirement to remove gloves and wash hands on finishing work with radioactive materials.

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Element IB8: Psycho-social agents

IB9: PSYCHO-SOCIAL AGENTS

1 Hospital nurses are at risk from work-related violence when they are required to visit patients in their own homes.

(a) Outline a strategy that the hospital management should have in place in order to manage work-related violence. Marks:10

(b) Describe a range of practical measures that the nurses can take to minimise the risk of violence when making

visits to patients. Marks:10 ANS

(a) The key elements of a strategy that the hospital management should have in place to manage work related violence (WRV) include

The preparation of a written policy defining the term, stating the management’s zero tolerance attitude to violence to their staff and indicating their support for legal action should this occur;

The identification of groups particularly at risk; The provision of adequate resources to control and minimise the risks associated with wrv; The introduction of procedures for reporting, recording and investigating incidents of violence; The identification of personnel with particular responsibilities for managing wrv such as carrying

out the risk assessments, receiving reports of instances of violence and monitoring compliance with control measures introduced as a result of the assessments made;

The provision of training to workers on how to deal with situations where violence might occur and Introducing a mechanism to support those who have been the victims of wrv such as counselling and

maintaining confidentiality.

(b) There are many practical measures that nurses might take to minimise the risk of violence including: Informing colleagues of the location and time of visits with appointments being made for the

hours of daylight and leaving a written record in the office with the anticipated time of return; Checking out the history of the patient prior to the visit for violent marker flags on the records and

dependent on the level of risk, either visiting in pairs or requiring the patient to come to the hospital; Carrying a mobile phone, radio or personal alarm and agreeing a code word when calling for assistance; Wearing appropriate clothing and refraining from wearing or carrying items of value; Planning the journey route to minimise risk and parking the vehicle in a way and in a location to

facilitate a speedy exit if required; and Training employees to spot the early signs of violence and to ensure that confrontation is avoided.

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2 Outline the meaning of the term „work-related violence‟. (2) (b) Outline a range of practical measures to help reduce violence towards a nurse who is required to visit patients in their own home. (8) Most candidates were able to answer part (a). Part (b) required practical measures such as

- familiarising with patient notes prior to the visit to identify previous incidents or indicators that violence might be more likely. Violence avoidance measures would include courteous behaviour, diffusing aggression and not carrying valuables. Violence may escalate, so making provision for a quick exit (vehicle parking, exit routes) as well as carrying means to call help were also relevant. Some candidates gave high level, strategic measures, such as policy and procedure development, rather than practical measures.

3 RRC - IB9 – SAQ3

Outline appropriate procedures to minimise the risk of violence to local authority employees required to make official visits to people’s homes. (10) Procedures to minimise the risk of violence to local authority employees required to make official visits to people’s homes would include:

The identification of risk factors through the risk assessment process. This might be done at a strategic level within the organisation to start with. However, local procedures might

be developed that require a risk assessment for each home visit. Development of an organisational policy on violence within the workplace in general and violence associated

with home visits in particular. The provision of information about risks to employees, so that they are aware of policy and procedures and

are able to make informed decisions as to their own work. Various types of training for employees. This would include training to enable the employee to provide a

good service, hence avoiding frustration and annoyance on the part of the client, one of the triggers for violence in the first place.

Training might also include interpersonal skills, to allow employees to moderate their own behaviour to avoid trigger points and reading the tell-tale signs of building anxiety or annoyance in others.

This type of training can be taken a step further into diffusion training, where active aggression recognition and handling skills are taught. Break-away training might also be taught, to allow an employee who is physically attacked to get away from their attacker with the use of reasonable force.

Communications equipment would have to be provided and some form of calling-in protocol developed. This is usually carried out just prior to and immediately after each visit. This may require the logging of intended

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routes and remote supervision of lone workers out in the field. Lone-working should be avoided where possible and in some instances may be banned (in certain areas or

with certain clients). Staffing levels will have to be maintained so as to permit these kinds of visits to be done in pairs.

Client inspection will be appropriate and notes kept on clients who do have a history of violent incidents. This might also be done in liaison with other agencies.

Reporting procedures and paperwork will have to be developed and broadcast, so that incidents are brought to the attention of management.

Emergency procedures would have to be developed, so that an immediate planned response can be carried out in the event of incidents such as hostage taking. This might include the use of key words or phrases to alert supervisors of risk without alerting attackers.

Valuables such as cash, laptops, etc. should not be carried as they act as a trigger for robbery. Attention must be paid to the clothing worn by employees, avoidance of loose clothing that is easy to grab

and hold and use of clip on ties. Simple rules such as visiting during the hours of daylight, parking in publicly visible areas, parking so as to be

able to drive straight out of the parking bay, etc. should be developed and communicated.

4 (a) Outline the physical, mental and social effects of stress at work. (3) (b) Identify a range of information sources an employer could use to determine the extent of employee work-related stress within an organisation. (7) (a) The physical, mental and social effects of stress at work can be considered using the following sub-headings: Physical Stress increases heart rate and blood pressure. As a consequence, headaches are often experienced. In the long term, heart disease and hypertension can occur. Muscle tension is another common symptom, along with increased sweating. Mental Chronic stress can lead to loss of self-confidence and self-esteem. This in turn can lead to depression. A sufferer may find mental processing difficult and may struggle to make simple decisions. Their ability to control their emotions may suffer with the effect that they may become withdrawn or suffer mood swings and perhaps be prone to aggression. Social As mentioned above, sufferers may become socially withdrawn, may turn to alcohol, prescription drugs or non-prescription drugs. Absenteeism from the workplace may increase. Family breakdown may occur.

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(b) There are a range of information sources that an employer can use to determine the extent of employee work-related stress within an organisation.

A key indicator is the level of sickness absence, assumed to be related to stress levels, and also the level of productivity in terms of volume and quality.

Accident data may also cite stress as an underlying cause. Performance appraisals will allow staff to raise stress issues, as will return to work and exit interviews. Discipline problems, grievance issues and staff complaints may all give indications of a stressed workforce, as

will comparatively high staff turnover statistics. Health surveillance data will provide direct evidence of stress related symptoms and poor or erratic

timekeeping is also another indicator. Finally, responses from staff questionnaires and also informal discussions with staff will allow feedback from

staff on potential stress situations. Measures of productivity (such as volume or quality of work), data on accidents and incidents and levels of

sickness absence; Records of staff turnover and poor or erratic timekeeping; Information available from the completion of staff questionnaires or from performance appraisals or return

to work or exit interviews and the results of an assessment of performance carried out against published stress management standards.

5 Managers are concerned at the increase in stress-related absence.

(a) Identify a range of information sources that can be used to assess the levels of stress experienced by their workers. Marks:6

(b) Outline organisational and personal factors that can contribute to the incidence of work-related stress.

Marks:14 ANS

a) Source of information could have included: - Face to face discussion between staffs and line managers or supervisor, either informally or formally at, for

example, performance appraisal - Discussion at safety committees or team briefings - Sickness and / or absence data and return to work interview; - Formal or informal complaints - Staff turnover data and exit interviews

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- The use of a structured staff questionnaire with the appropriate analysis - And published external guidance and standards

(b) The factors that could increase the probability of stress occurring and apply them to a bank scenario.

The demands of the job ( for example work overload or under load, monotony, poor physical environment, threat of violation);

The amount of control that staff have over the way they carry out their work (citing lack of communication and consultation)

The degree of support offered by the organization and management and colleagues Work relationships (bullying, harassment, mistrust) Role – conflict , lack of clarity etc Mismanagement in organizational change leading to insecurity

5 You have been asked by the Board of a multi-national bank to provide advice on occupational stress. Prepare a briefing note for the Board of the bank that describes:

(a) the sources of information that may be used to assess the risk of high levels of stress; Marks:8

(b) The occupational factors that can contribute to the incidence of stress- related problems amongst bank employees. Marks:12

Jan, 2008

6 RRC - IB9 – SAQ3

Identify: (a) FIVE major causes of stress at work. (5) (b) FIVE strategic management issues to be addressed in order to reduce or eliminate the causes of stress at work. (5) (a) The major causes of stress at work include:

Unreasonable pace of work – being asked to meet unrealistic deadlines with inadequate resources and support.

Lack of control over work – not having the power and authority to make changes to the type of work done, the work methods used, work priority or even environmental factors associated with the workplace, such as workstation layout, temperature, etc.

Inadequate managerial support – poorly developed management policies and poor support on a day to day basis.

Demanding work schedules – shift work, shift patterns and changes of shift pattern, in combination with long

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hours of work and inadequate rest breaks. Feelings of isolation – notable social isolation within the workplace, which may result from physical isolation or

may result from workplace culture. Bullying and harassment – either overt or covert of any employee by any other employee, though this is

usually the bullying and harassment of a junior worker by a more senior worker. Physical work environment factors – such as lighting, temperature, noise, space, etc.

(b)

Positive organisational culture (objectives, communication, staff involvement). Careful management of change (flexibility, openness, fairness). Clear role definition (clear responsibilities, role in the organisation). Job design and staff selection (job should match skills and abilities, need for training). Work schedules (flexible, agreed, and reasonable). Work relationships (interpersonal skill training, grievance procedures).

7 RRC - IB9 – LAQ1

Outline the factors to consider when undertaking an assessment on the moving and handling of patients in a hospital. Marks:10

Jan, 2008

8

RRC-ib9 – LAQ 2

b

In your role as a health and safety advisor you have been asked to prepare a company policy on drug and alcohol misuse. Explain the key points that such a policy should include. Marks:10 A health and safety policy on drugs and alcohol misuse should contain the following key points:

A statement of general intent, i.e. the aim of the drug and alcohol policy. Usually something like; ‘Prevent risk to employees and others and prevent detrimental impact on business performance through the misuse of drugs and alcohol within or outside of work’.

An indication of roles and responsibilities; i.e. the responsibilities of senior management, human resources, health and safety department, managers and employees with regard to this policy.

Definitions of drugs and alcohol misuse so that employees are clear about the meaning of the terms and phrases and understand that the policy does not just cover drug and alcohol taking within work hours or on work premises.

Clear statements of what the rules are with regards drug and alcohol misuse. Here there needs to be absolute clarity about what constitutes unacceptable behaviours (such as drinking on work premises, drinking during breaks, drinking at works parties) and clarity about what constitutes drug issues (with clear rules about illegal

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drug taking and prescription drug misuse). A clear policy commitment must be made to workers who wish to admit to misuse and require help.

Counselling and rehabilitation should be offered. A clear policy statement on the disciplinary consequences of misuse must be made. Possession of illegal drugs

should be treated as gross misconduct. Possession of alcohol might be treated in the same way (depending on the nature of the workplace). Failure to cooperate, in any counselling or rehabilitation service offered on identification of a problem, should

also be treated as a disciplinary offence. If drugs and alcohol testing is to be made a feature of company policy, then some very clear policy statements

need to be made about this. o The reasons for testing will need to be explained clearly. o The methods of testing, and substances to be tested for, will need to be explained and the

consequences of positive results, or failure to supply a sample, must be explained. o Confidentiality must be assured.

9 Outline the occupational factors that can contribute to stress-related problems amongst call centre workers. Marks:10

Occupational factors that can contribute to stress-related problems in the scenario described include work overload or underload with unacceptable work patterns;

An adverse working environment with overcrowding and unacceptable levels of lighting, temperature and noise; a lack of consultation and participation in how the work is carried out;

A lack of encouragement from management and colleagues with little opportunity given to raise any problems that might arise;

A lack of support given by the organisation for further training or education; Cultural differences such as language, religion and ethnicity; Being required to cope with unacceptable behaviour such as bullying, harassment and violence leading

to a lack of trust in colleagues; A lack of understanding of their role in the organisation since this has never been made clear by management

with the result that several workers have conflicting roles; and Excessive organisational change with the resulting fear of job security and redundancy fuelled by a lack of

communication by management of the nature of the changes that are to or have been made.

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10 R9 –

LAQ 2 c

(c) Identify the types of circumstances in which an employer may consider using drug screening and testing as part of their approach to managing drug and alcohol issues. (3) The occasions when an employer might consider using drugs and alcohol testing or screening might be:

When required to do so by statute law (e.g. law governing the operation of trains and railways). On suspicion of a problem either because of employee behaviour or because of information that has been

supplied by other concerned persons (anonymous tip-offs are common in these circumstances).

Where the work is safety critical and, therefore, impairment of workers might result in risk to themselves, others and the public (e.g. a crane operator).

After an event, where post incident investigation has shown that drug and alcohol misuse was a significant causative factor.

As a part of an individual’s rehabilitation into the workplace, when they are known to have had a problem with misuse and have agreed to screening as an alternative to dismissal

Q7. Jan 2013 (b)

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Element IB9: Musculoskeletal risks and controls

IB10: ERGONOMIC FACTORS

1 (a) Give the meaning of the term ‘ergonomics’. Marks:2

(b) Outline the effects on health and safety which can arise from poor ergonomic design. Marks:4

(c) Lifting and handling aids are frequently used to reduce the risk from manual handling when lifting loads.

Outline the factors to consider when selecting lifting and handling aids. Marks:4

(d) Outline the factors which should be considered to minimise ergonomic risks to their workers when

purchasing and then using the laptops. (10)

ANS (a) The term ergonomic principles is defined as designing the workplace, work methods and work equipment to suit the worker or ensuring a good fit between the person and their workplace as far as tools, equipment and workstation are concerned. (b) The effects on health and safety from poor ergonomic design include physical harm in terms of discomfort, fatigue, back strain and work related upper limb disorders (WRULDs) as well as mental harm as evidenced by increased stress, lack of motivation and an increase in error leading to accidents or incidents. (c) Factors to be considered would include seeking advice and information from suppliers, occupational health nurses and hygienists;

Observing solutions in use from similar industries and if possible trying out a variety of aids before purchase. It will be important to check that the aid is in conformity with the relevant standards; That its safe working load is suitable for the work to be done; To ensure that it can be used where there may be space constraints and to enquire as to its maintenance

requirements; The suitability of the safe working load or conformity to standards; The influence the selection process on the lifting and handling aids.

(d) The initial selection and purchase of the equipment is of prime importance if the computer is to be used on the move where consideration would need to be given to the provision of as large a screen as possible;

To the weight of the equipment which should be as small as possible; To the provision of light weight carrying cases or trolleys and to the provision of friction pads to stop the

computer slipping during use. During home use consideration would have to be given to the provision of a separate mouse and keyboard and

a separate screen or docking station as well as the provision of other workstation equipment such as a chair

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and desk.

2 Operatives on a food manufacturing production line have to pick up rectangles of pasta from a delivery conveyor and place them into foil trays on a separate conveyor. This involves 8 hour shifts and is carried out standing in front of the conveyor. or Workers on a food production line have to pick up rectangles of pasta from a delivery conveyor and place them into trays on a separate conveyor. This involves 8 hour shifts and is carried out standing in front of the conveyors. Following complaints from a number of workers about pains in their arms and shoulders, you have been asked to carry out an ergonomic assessment for this operation.

(a) Outline the ergonomic risk factors to be taken into account when making such an assessment AND outline how these may be contributing to the problems experienced by the workers in this situation. Marks:5

(b) Total automation of the process is not possible.

Outline other control measures that could be taken to reduce the ill-health effects being experienced by the workers. Marks:5

ANS

(a) In carrying out an ergonomic risk assessment of the operation described in the scenario, the factors that would need to be taken into account include

The individual factors, such as worker height; The repetitive nature of the task involving frequent movements of the upper body to pick up the pasta

and place it in foil trays; The continuous nature of the operation over an eight hour shift; The posture adopted by the operators including standing and reaching from one conveyor to another; The expected work rate and the speed of the conveyors; The height of the conveyor in relation to that of the individual workers and the total pattern of

continuous work with the number and length of the breaks allowed. (b) Control measures to reduce the ill-health effects include

Adjusting the height of the conveyors and re-positioning them in parallel; Arranging the work so that it might be carried out from both sides of the conveyor to prevent

over reaching;

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Providing seating for the operators to enable them to change their position from time to time; Reducing the speed of the feed conveyor; Using scoops or other tools to pick up the pasta; Introducing job rotation with other less demanding tasks; Providing information to the workers on the benefits of changing their posture and stretching on a

regular basis; carrying out pre employment health screening to determine existing problems which might make applicants unsuitable for the task and introducing health surveillance and encouraging workers to report any problems that might arise.

3 A worker on a production line is required to stand in front of his workbench, which is 750mm deep and set at waist height. The worker must frequently lift a 20kg item of equipment from his workbench onto an unpowered roller conveyor which is behind it. The conveyor is set slightly higher than the workbench (see diagram).

(a) Explain why the current method of working is not acceptable. Marks:4

(b) Outline practical measures that might be considered to reduce the ergonomic related risk to the worker.

Marks:6

Q5. Jan, 2012

JULY 2013

4

A parcel sorting depot is experiencing a high number of manual handling related injuries. The employees handle a large number of different parcels and packages each day.

(a) Identify the different types of hazard that may be inherent in the loads being handled. Marks:6 (b) In order to reduce the level of manual handling required, the employer has decided to invest in a range of

non-powered handling devices, (trolleys, trucks etc). Describe the steps that should be taken when selecting such devices and introducing their use. Marks:10

(c) Outline a range of additional control measures that could be introduced to minimise the risks associated with manual handling. Marks:4

(a), the different types of hazard that could have identified included:

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Weight of load and the fact that the weights would be unknown; Parcels may be difficult to grasp, as they are likely to be smooth with no handholds with unstable contents

which are likely to move or with the centre of gravity not in the centre of the parcel; Awkward shapes would be common or parcels that are too large for the handler to see over; Sharp edges or corners and the possibility that the contents might spill out, some of which could be hazardous.

(b)

Splitting the parcels into two sections dealing first with the selection of the devices and then with their introduction. The selection of the handling devices requires consultation with the employees both in the selection and the trials; seeking advice from suppliers on suitability;

Requesting equipment on a trial basis to check whether it solves the problem without creating new Ones; Observing the equipment in use at other organisations; Considering the requirements for maintenance; Ensuring the proposed use will be within the safe working load of the device; Ensuring there is sufficient room to manoeuvre; Ensuring the suitability of the device in the light of the stability and surface of the terrain on which it was to be

used; Checking that braking controls were adequate and that the handle height was adjustable between waist and

shoulder; and That the design of the equipment was such as to prevent parcels from falling off. As far as introducing the use of the devices, this would require consideration of operator training, storage

when not in use, maintenance arrangements and a procedure for reporting defects; and Ensuring there are a sufficient number of devices available which are readily accessible.

5

RRC-IB10- SAQ1

Outline the factors that should be considered in relation to the job, the individual and the work environment when carrying out an assessment of ergonomic risks in a workplace. Marks:10 Plan Job – duration, posture, force, movements, repetition, pace. Individual – physical attributes (height, weight, age, reach); mental abilities and skills; specific groups (young workers, etc.); level of training received. Environmental – space, temperature, humidity, lighting, etc. Job factors relating to ergonomics include

Consideration of the demands of the task, such as the duration, repetition, the work rate and the

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opportunity to take breaks. The equipment that a person uses as part of the job can affect the ergonomic risks in a number of ways such as

the amount of force or effort required to operate the equipment as well as the design and layout of the controls.

The postures that are adopted when carrying out the job, whether or not equipment is involved, can increase the risks, especially if these postures are awkward or involve frequent twisting, stretching or prolonged stooping.

The individual factors include

The stature, shape, strength, and general fitness and mobility of the individual; Gender, age and sensory abilities such as hearing and vision An individual’s mental capabilities, level of experience, knowledge and level of training should also be taken

into account. Finally, the physical aspects of the working environment, such as lighting, temperature, noise, humidity, space and floor conditions also need to be considered as part of any ergonomic assessment. Many candidates provided good answers for this question though there were some who perhaps did not read the question with sufficient care and described how a risk assessment for the use of display screen equipment should be carried out.

6 Outline the specific measures that a company should put in place in order to minimise the risks of ill-health associated with the use of Display Screen Equipment. Marks:10 or (a) Outline the ill health effects that might arise from use of display screen equipment. (6) (b) Outline the key factors to be considered in assessments of workstations for users of display screen equipment. (14) Plan (a) Musculoskeletal injury and discomfort Eye and eyesight effects Fatigue and stress

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(b) Equipment – screen, keyboard, mouse, document holder, desk, chair, footrest. Standards for each. Environment – heating, noise, radiation, lighting. a) The ill-health effects that might arise from the use of display screen equipment can be broadly grouped into three areas. The first arises from poor ergonomics and includes musculoskeletal injury and discomfort arising from excessive periods of continuous intensive keyboard work at a badly designed workstation. The second includes eye and eyesight effects such as sore eyes and headaches produced by poor position and legibility of display screen equipment screens. The third effect results from poor job design and organisation and can cause fatigue and stress. b) The factors to be considered in undertaking a workstation assessment for a DSE user are listed in the Schedule to the Regulations and cover the equipment, the environment, ergonomic factors and the systems being used. The equipment includes the screen, keyboard, mouse, document holder, desk, ancillary equipment on the desk, chair, footrest, etc. An important factor here is that the equipment should be suitable for the user in question and should be appropriate to the type of work undertaken. Thus, a pool typist may have a document holder to allow easy transfer from paper to screen. However, an accountant may rely on spreadsheets so no document holder would be necessary in this instance. There are minimum standards for many of the items of equipment listed. The screen for instance should tilt and swivel and should have a stable, focused image. The desk should have enough space to be able to arrange all of the equipment on it in an ergonomic manner. (For example; mouse to front of desk, not tucked over the back of the keyboard. The chair must have a stable five-star base, adjustable height seat, adjustable height backs and adjustable tilt for the back too. The desk must be the right height for the user to adjust their chair to give a proper sitting position. They should be able to get their feet on the floor. If not, they will need a foot rest. The user should be able to position the screen straight in front of them, with the top of the screen at eye height. There must be sufficient room to position the keyboard between the screen and user, with space for a wrist rest if desired. With regards the environment there are various factors mentioned here – heating, noise, radiation, but by far the most important factor is the availability of properly designed workplace lighting. This may be in the form of daylight, or strip light or lamps. However the lighting is supplied, it must be appropriately

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positioned or adjustable to avoid reflection and glare on the screen. Windows should have blinds.

7 A company has decided to provide home workers with portable (laptop) computers for use at home and on their daily visits to customers. Outline the factors which should be considered to minimize ergonomic risks to their workers when purchasing and then using the laptops. Marks:10 When selecting a laptop for use on the move, major considerations are size, weight and ease of transporting. When it is used at home, there are more opportunities to improve comfort by providing a separate keyboard, mouse, screen and other items. Since this would be a significant change, relevant risk assessments would need to be reviewed. Any training provided should focus on assessment of the ergonomic risks likely to be encountered (on the move and at home) and the associated control measures to be adopted.

Q3. July 2012 Jan, 2009

8

RRC - IB10 SAQ2

Work Related Upper Limb Disorders (WRULDs) can develop whilst carrying out work including assembling components on a production line, preparation of filtered coffees in coffee shops or supermarket cashiers handling and packing shopping items.

(a) Identify the signs and symptoms of WRULDs. Marks:2 (b) Outline control measures that could reduce the risk to workers of developing WRULDs. Marks:8

(a) The signs and symptoms of WRULD includes tenderness or pain in the shoulder, arms and even neck; stiffness and weakness and tingling, numbness and cramp. (b) Control measures that could reduce the risk to workers of developing WRULDs include reducing repetition by breaking up the periods of work and introducing several short breaks; reducing the amount of force required to complete an operation by the provision of lightweight tools; reducing the distance an item has to be moved and eliminating the need to lift the item by using alternative methods such as sliding; maintaining handles and controls to avoid the need for unnecessary force; providing supports, jigs and counterbalances; and ensuring that the correct tools are used for the operation and that they are maintained on a regular basis. Additional measures would involve finding the correct working position by designing work equipment for workers of differing size and build and those who are left handed and providing adjustable chairs and footrests and tools with a suitable size grip; improving the work environment by ensuring the working temperature is comfortable and that workers do not have to work in close proximity to air vents and air conditioning system outlets, and ensuring a good standard of lighting avoiding reflection and glare and using local lighting or personal lamps where these are thought to be necessary. Finally the possibility of job or worker rotation should be considered with the introduction of warm up activities before starting work.

Q3. Jan 2013 Jan, 2010

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RRC-IB10-SAQ-1

Identify the ergonomic factors associated with the risk of injury to airport baggage handlers and outline how the level of risk can be reduced. (20) Jan 2013, UNIT C Factors: Task – lift, move, place, frequency breaks. Load – size, shape, weight, centre of gravity. Environment – indoors/outdoors, weather, space constraints, lighting, noise, temperature. Individual – physique, fitness, health, ability. Controls: Elimination – trucks, roller or belt conveyors. Mechanical handling aids – motorised pallet trucks, hoists, etc. Manual handling aids – trolleys, sack truck, etc. Training – team lifting, labels, staff selection. Occupational health policies.

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Element IB10: Work environment risks and controls

IB10.1 Explain the need for, and factors involved in, the provision and maintenance of thermal comfort in the work environment IB10.2 Explain the need for adequate and appropriate lighting in the workplace, units of measurement of light and the assessment of lighting levels in the workplace IB10.3 Explain the need for welfare facilities and arrangements in fixed and temporary workplaces IB10.4 Explain the provision for first aid in the workplace.

1 The most widely used and accepted index for the assessment of heat stress in industry is the Wet Bulb Globe Temperature (WBGT) index.

(a) Identify the measurements that need to be taken to determine the WBGT index. Marks:3

(b) Outline the principle of operation of the instruments that should be used to make the measurements. Marks:7

(a) The measurements that would need to be taken include the wet bulb temperature, the air or dry bulb temperature and the radiant or globe temperature. (b) The principles of operation for the wet bulb temperature, a thermometer with the bulb wrapped in a wetted cloth or sock is used.

The water evaporates from the bulb causing it to cool. The bulb cools to below the ambient temperature giving a measured wet bulb temperature. Air temperature is measured using an alcohol/mercury or digital thermometer. The liquid in the tube expands as the temperature rises and a reading obtained from a marked scale or digital

display. A black globe thermometer is used to measure radiant temperature. A mercury filled thermometer is encased in a black painted copper sphere and the radiant heat is absorbed

without being influenced by air currents.

July, 2011

2

RRC – IB8-

LAQ2

(a) Identify the possible health effects from working in a cold store at sub-zero temperatures. Marks:4

(b) Outline control measures to minimise the risks to persons who work in a cold store at sub-zero temperatures. Marks:6

ANS

(a) There are many possible health and safety risks associated with work in sub-zero cold stores.

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The health effects include: Frost bite – where tissues freeze as a result of the extremely low temperatures. These types of injury can lead to loss of extremities such as fingers and toes. Hypothermia – where the core temperature of the individual drops below 35°C, leading to difficulty with physical and mental processes, erratic behaviour and ultimately loss of consciousness. Chilblains – where the skin becomes red, inflamed and sore.

The safety hazards include:

Slipping on icy floors and all of the resultant injuries. Being locked in the freezer and suffering hypothermia as a result, perhaps coupled with inability to raise an

alarm. Slowness of mental processing (torpor) as a result of hypothermia. Inability to handle objects in thick gloves and the inability to move easily when kitted up in all of the PPE that

would be required. The materials used may be affected, especially metals; these could be subject to brittle fracture.

(b) The precautionary measures that may be taken to protect people working in sub-zero environments include:

Warm clothing such as hat, balaclava, quilted jacket with layers underneath, quilted trouser, thick thermal socks, thermally insulated boots, insulated gloves.

Frequent rest periods outside the freezer in a warm atmosphere. Hot drinks and access to hot food, or food heating facilities. Limits on the time of working in the cold, perhaps in association with job-rotation. The provision of, and storage facilities for, clothing. Equipment and procedures for the removal of ice from the floor. Emergency lighting inside the sub-zero area. An entrapment alarm that can be activated from within the freezer, but is audible to staff outside the freezer. Quick release handles to open doors from both sides. Health surveillance for workers.

3 A process in a textile mill produces high levels of heat and steam. RRC-a The possible adverse effects on health from working in such an environment.

(a) Identify FOUR parameters that could be measured when making an assessment of the thermal environment stating in EACH case the name of an instrument that can be used to measure this parameter. Marks:4

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(b) Outline the ways of reducing thermal stress amongst employees in the textile mill, with reference to both the thermal environment AND other controls. Marks:6

RRC-a: (a) The possible adverse health effects that could occur from working in the thermal environment present in the mill would include:

Increased pulse rate leading to higher blood pressure. Dehydration; as a result of increased sweat rate. Dehydration will lead to loss of water from the blood, making

the blood thicker and consequently harder to pump around the circulatory system (hence increased blood pressure).

Muscle cramp; as a result of loss of sodium from the body in sweat (sodium is important for the correct functioning of muscles).

Fatigue, dizziness and fainting; as a result of dehydration and heat stress In extreme examples, core temperature spirals out of control and the casualty will suffer from heat stroke; loss

of consciousness as a result of overheating. This is a dangerous condition that can lead to coma and death. Skin irritation; as a result of high humidity levels and excessive sweating. This can in turn lead to dermatitis

and fungal infection of the skin. (b) The parameters associated with the thermal environment that should be measured would include: Ambient temperature – the temperature of the air within the workplace, discounting any contribution from radiation. This would be measured simply using a dry bulb thermometer (usually mercury bulb type). Air velocity – the rate of movement of air within the workplace. Measured using an anemometer or kata thermometer (a larger alcohol filled thermometer that measures the cooling influence of air movement). Relative humidity – the amount of water vapour in the air measured relative to the total amount of water vapour that could be held in saturated air at the same temperature. This might be measured using a whirling hygrometer – also known as a sling hygrometer or a psychrometer – (a device rather like a football rattle with a wet bulb and a dry bulb thermometer mounted on it). Radiant heat – a measure of the amount of infra-red radiation that is present in the workplace, which makes a contribution to heat gain. Measured using a globe thermometer; a matt black metal sphere with a dry bulb thermometer in it.

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(c) Precautions to reduce thermal stress. The risks associated with working in this type of environment could be managed, in the first instance, by paying attention to controlling heat generation at source. This would be done by shielding workers from infra-red heat sources (radiant heat sources), lagging all hot surfaces (such a steam pipes), preventing the escape of steam from process machinery into the work environment and, where steam escape cannot be prevented, by extraction of that steam. If it proves impossible or impractical to prevent the escape of heat and steam into the work environment, then that environment should be managed by engineering controls to try to reduce the impact on workers. This could be done using adequate workplace ventilation and de-humidification. Attention will also have to be paid to providing adequate fluids for workers so that they can drink freely and easily to avoid dehydration. Drinking water may have to be supplemented with isotonic fluids and/or salt tablets. Suitable clothing that allows workers to sweat freely, yet provides them with adequate protection from other workplace hazards, must be sourced and supplied. The number of workers exposed to the more extreme thermal environments in the workplace must be kept to a minimum. Job rotation and the provision of adequate breaks is another key control. Pre-employment screening in combination with health surveillance may be required, especially for workers in the more extreme environments and those with known health problems. Training must be provided to all workers, to include the health issues associated with working in a hot and steamy environment and the various controls and precautions necessary. Workers may need to be given the opportunity to acclimatise gradually to the more extreme parts of the workplace. Adequate supervision must be maintained through-out.

08-IC1 - 05

A vegetable packing plant employing 200 men and 60 women is about to open. OUTLINE the specific welfare arrangements that need to be provided before the plant opens. Marks-10 / 20

Sanitary Conveniences: Sufficient numbers of well-lit and ventilated sanitary conveniences - Maintained in a clean and tidy condition. - Provision of Toilet paper, a coat hook - Separate rooms or blocks for men

and women (or capable of being locked from inside if the sanitary conveniences in the same room). Washing Facilities: Sufficient numbers of well-lit and ventilated washing facilities - Changing rooms and Showers to be provided

and maintained in a clean, tidy condition - Supply of hot and cold or warm running water, - Soap and a means of drying

Drinking Water: An adequate supply of drinking water with cups - Readily accessible, located away from sources of contamination

- Marked conspicuously

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Accommodation for Clothing / Facilities for Changing Clothing: Clothing accommodation with a hook/peg located in a clean, warm, dry, ventilated place should be provided for each worker to hang their own clothes if not worn during the working day.

- Changing facilities separate for men and women and contain means of drying wet clothing and separate storage of contaminated clothing - Decontamination facilities with shower and a clear division between clean and dirty areas

Facilities for Rest and to Eat Meals: Rest and eating facilities - Readily accessible, contain adequate seating and tables - Be maintained in a clean condition - Arrangement for preparing and heating food and for boiling water - Means or procedure for preventing contamination of the area where food and drinks are taken - Rest rooms and areas should be arranged to ensure that non-smokers do not have to be exposed to smokers -

separate rooms/areas, prohibition. - Adequate Facilities for nursing mothers and pregnant women to rest. First aid facilities including trained personnel taking into account the number of persons employed and the

proximity of emergency services

2-IC1-05

(a) OUTLINE the possible health and safety effects of inadequate workplace lighting. Marks-4 (b) OUTLINE the factors that should be considered to ensure that lighting in a workplace is adequate. Marks-16

a). Health effects includes: headache, visual fatigue , eye strain, blurred vision; -inadequate posture creating neck and backache to get adequate VIEW for the tasks to be performed. - Safety implications : likely to increase the incidents such as slip, trip and fall, striking with objects because of insufficient

lighting arrangements causing unidentified objects – wrong type of lightings which are creating stroboscopic effects - Human error which may put others at risk

- Factors that should be considered: - The type of work to be taken - The amount of precision required and whether tasks require general, local and/or localised lighting - The level of natural light available - The workplace layout giving attention to the effects of screens, furniture or racking - the considerations of those objects casting shadows - The different types and level of lightings required for stairs, corridors and outside security lights. - The level of lighting in adjacent areas in order to avoid the effects of moving from a strongly lit area to one which is dimly lit and vice versa; - The individual needs of the employee whether on account of age or disability - The possibility of glare on display screen - The colour and type of lighting fitted o prevent stroboscopic effects - The need for emergency lighting particularly for fire escape routes - The need for portable lighting when work has to be carried out in confined space - The ease of maintenance whether replacing spent bulbs or cleaning the light fittings for probable - All glazed windows and skylights used for the lighting of workrooms shall, so far as is practicable, be kept clean on both the inner and outer surfaces and free from obstruction, OUTLINE the health and safety issues which should be identified during a lighting audit of a factory which includes production, maintenance workshops and offices

Jan, 2012 Jan, 2009

JULY 2013

4 (a) (i) Identify SIX factors that can affect the thermal comfort of an individual. Marks:6 (ii) Outline the role of heat indices when assessing a thermal environment. Marks:3

(iii) Give an example of a heat index AND identify the parameters that contribute to this index. Marks:3 (b) Catering staff prepare chilled meals for reheating. A significant part of their working day is spent in an area where the ambient

temperature is between 3° and 5°C. Describe the control measures that could be used to minimize the risks associated with working in this cold environment. Marks:8

Q11 Jan 2013

July, 2009

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Element IB11: Managing occupational health On completion of this element, candidates should be able to demonstrate understanding of the content through the

application of knowledge to familiar and unfamiliar situations and the critical analysis and evaluation of information presented in both quantitative and qualitative forms. In particular they should be able to: IB11.1 Outline the nature of occupational health IB11.2 Outline the principles and benefits of vocational rehabilitation including the role of outside support agencies IB11.3 Outline the management of occupational health (including the practical and legal aspects).

01 Dental practitioners often work alone or with small teams. (a) Identify the health hazards to which a dentist and those who work with dentists may be exposed. Marks:10

(b) Outline how the risks to a dentist and those who work with dentists can be reduced. Marks:10

Plan for All types of hazards: Fire, Hazardous substances, biological, mechanical / drill, electric, vibration, X-rays, violence, stress, gen – slip, trip fall

(a) The health hazards to which the dentist and their working staff may be exposed include Chemical, Biological and Ergonomic. Chemical hazards arise in the use of sterilizing agents, pain killers anesthetics, dental / filling materials for

example mercury and photographic chemicals used in developing x-rays. Biological hazards may be inherent in the work undertaken. Patient may carry blood borne pathogens such as

hepatitis or HIV that present a serious risk of infection to staff and to other patients. This may also arise from contact with body fluids and/or clinical waste and from accidental inoculation whilst using sharps.

Vibration hazards will be present in the workplace, though small, dentists’ drills vibrate at high frequency and because they are pinched firmly between thumb and forefinger, the potential for localized injury exist (VWF).

Ergonomic / Musculoskeletal problems are inherent in sitting at a workstation typing in data. This may be a risk of particular importance to reception and office admin staff

The possibility of ergonomic hazards would arise from positions necessarily adopted over the dental chair, from handling elderly patients and from the use of display screen equipment.

Radiation hazards presented by x-ray equipment in the practice. Health hazards also include those created in the use of x-rays or ultraviolet light, allergy to latex gloves, stress

from overwork and the possibility of violence from aggressive patients.

(b) The hazards identified can be controlled by using some general management principles. Such as Risk assessment (identifying the hazards, the persons exposed, an evaluation of the risks involved and the

control measures that should be introduced) should be carried out to verify these hazards and correctly evaluate the risks presented and the control necessary.

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The development of safe system of work and operating procedure is an important requirement that would have special relevance to some of the hazards identified (e.g.; operation of the x-ray generator, and ssws to control the risk from violence)

Staff selection and training would be critical to control many of identified risks. The dentists, their technicians and ast would all have to be suitably qualified and experienced. They must have specific training in order to adequately control the risk inherent in certain operations – such as use of x-ray equipment or the administration of anesthetic drugs.

In the case of control measures consideration would have to be given to the substitution of hazardous with less hazardous materials where this was possible and practicable;

The provision of adequate ventilation and suitable and adjustable seating which would eliminate the need for standing and bending for long periods;

Introducing controls for the use of x-ray equipment such as time, distance or the provision of barriers; Personal monitoring would be of great importance in the control of personal radiation dose. Ensuring adequate facilities were provided for the sterilization of equipment and the disposal of contaminated

sharps; Introducing policies to deal with the problems of stress and violence; Providing and wearing suitable PPEs such as overalls, masks and non-latex gloves etc. to control the biological

pathogens. The provision of training to all members of the team in safe working practices such as those connected with

manual handling, infection control, ionizing radiation and the handling of clinical waste.

2 Outline the four stages of occupational health and hygiene practice. Marks:4 An organisation is concerned about the level of absence arising from work related injuries and ill-health. Outline practical ways in which the organisation’s occupational health department could assist in the management of this problem. Marks:6 Answer:- The FOUR stage in occupational health and hygiene practice are

- Identifying factors that can cause harm in the workplace. - This would be followed by taking measurements to determine who might be affected and to what extent. - Once the measurements have been completed, an evaluation of the level of risk posed by the identified

hazards will have to be carried out and this will point to the need to - Introduce control measures to eliminate or minimize the risk.

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There are a number of practical ways in which the organisation’s occupational health department might assist in managing the problem described such as:

Using pre- employment screening to identify potential workers who would be at a greater risk of suffering ill-health resulting in absence;

Carrying out regular health surveillance of existing workers engaged in activities with known health hazards for example those exposed to lead;

Collecting data on sickness absence, analyzing it to identify trends or reasons for absence and training managers in the importance of monitoring absence from work;

Liaising with medical practitioners, arranging vaccination or immunization programmes and providing rapid access to treatments such as physiotherapy and counseling which will aid return to work;

Assisting managers to arrange phased return to work in certain circumstances and providing practical advice on adaptations to work practice to minimise risk of repeat injury; and taking an active part in carrying out risk assessments at the workplace.

3

Outline the role and functions that an occupational health service could have within a large chemical processing company. Marks:20 Or Draft a report to the Board of Directors of a large chemical processing company which outlines the role and functions that an occupational health service could have within the company. Marks:20 The role and functions an occupational health service might perform in the given scenario include

Carrying out pre-employment medical examinations and health screening and examinations of workers exposed to specific health hazards such as audiometry, skin examinations, lung function tests and lead in blood levels;

Return to Work Examinations for those workers returning to work after accidents or periods of sickness and o examinations connected with competencies for performing certain operations such as driving, and o Immunisation against for example TB, tetanus, flu and hepatitis; o Rehabilitation involving a physiotherapist or ergonomist;

Giving victim an immediate medical assistance following an accident and Assisting in the training and assessment of first aid personnel; Carrying out specific risk assessments with respect to

o the vulnerability of certain groups such as pregnant women and young persons, o new processes such as those involving potential ergonomic hazards such as manual handling, and

Specialist monitoring and testing involving airborne hazardous substances, noise and vibration;

Jan, 2010 Jan, 2009

July, 2007

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Providing training and counseling for manual handling, stress management, personal hygiene issues and post-traumatic stress conditions;

Keeping records of and analysing the reasons for sickness absences; and Providing an advisory service including health promotion, ill health and retirement, advice for travellers, advice

to management on the need for workers to be given restricted duties or re-deployment, liaising with appropriate external authorities and medical specialists and providing a medical input into emergency plans covering events such as major accidents and pandemics.

4

R1-SAQ1

OUTLINE the possible functions of an occupational health service within a large manufacturing company. 10 MARKS Plan Pre-employment, return-to-work assessments, biological monitoring, health surveillance, policies, risk assessments, health promotion, absence monitoring, records, first-aid, immunisation, counselling. Suggested Answer The possible functions of an occupational health service might include:

Pre-employment health screening for some or all workers. Return-to-work assessments where absence has been the result of injury or illness. Biological monitoring such as the carrying out of routine drugs and alcohol testing that may be a requirement

of company policy. Health surveillance, such as lung function tests of workers exposed to asthmagens, audiometry for workers

exposed to noise, etc. Contributing to the development of health and safety policies. Providing specialist input to risk assessments such as those for chemicals, manual handling and ergonomics. Health education and promotion, some of which may fall within the workplace remit, but some of which

might simply be the promotion of healthy lifestyle. Sickness absence monitoring. Keeping health records for employees, including ex-employees, for the required periods of time. Managing first-aid provision within the workplace, by involvement in the assessment of first aid need,

management of first aider training and performance. Liaising with enforcement officers. Management of any immunisation programme, such as Hepatitis, oversees workers, etc. Provision of a counselling service for workers experiencing psychological distress associated with work or home

life.

JULY 2013

5 A large manufacturing company is to introduce a health promotion programme. Jan, 2012

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(a) Outline the purpose of a health promotion programme. Marks:2 (b) Identify issues the health promotion programme should address AND outline the way in which EACH issue

could be promoted. Marks:8 (c) Identify FOUR occupational health specialists who may be involved in the health promotion programme, AND

outline how EACH specialist could contribute to the programme. Marks:10

7

RRC – SAQ - 3

A distribution company employs 300 workers as drivers, warehouse operatives and office staff, processing

telephone and internet orders. (a) Identify the possible functions of this company’s occupational health department:

(i) When recruiting new workers; (4) (ii) When a worker returns to work after ill-health. (5)

(b) Outline other ways in which the occupational health department can assist the management team to improve health and safety within this organisation. (11)

(You do not need to consider those functions you have already addressed in part a). Answer :- (a) (i) During the recruitment of new workers, the occupational health department would have an important

part to play in

Carrying out screening of the applicants and reviewing their health history so that they might be in a position to advice management on their suitability for employment.

In particular they would need to check the fitness and ability of potential warehouse staff to

undertake manual handling tasks, Check the eyesight of applicants for positions as drivers whether of road or internal vehicles

and also screen them for evidence of the possible misuse of alcohol or other substances. Additionally it would be important to carry out eyesight tests on those who would be employed in

the office to use display screen equipment. (ii) As for those workers preparing to return to work after a period of ill-health, an assessment of their current health condition would enable recommendations to be made to management on whether the return should be phased or whether the employee should be redeployed on other or lighter duties. This would necess i tat e l i a i s o n w i t h t h e employee’s GP and where necessary arranging for or even

providing counseling and rehabilitation treatment in house. Risk assessments may also need revising.

(a) Q1. Jan 2013

Jan, 2011 July, 2009 Jan, 2008

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RRC – SAQ - 3

(b) The ways in which the occupational health department could assist management in improving health and safety in the organisation include

- Maintaining health records of workers and carrying out monitoring of sickness absence; - Providing first aid treatment and training for workers appointed as first aid personnel; - Providing information and advice to workers on weight management, exercise and smoking

cessation; - Undertaking immunisation, health surveillance and environmental monitoring; - Providing training, for example in manual handling and the management of stress; - Providing an input to the development of policies and procedures and participating in

management team meetings and meetings of the health and safety committee; - Making a specialist input to risk assessments and liaising with the enforcement authority on

health issues

b Jan, 2011 July, 2009 Jan, 2008

RRC – LAQ3

Question 3 A soft drinks manufacturer employs 400 people undertaking a range of different jobs including production, warehousing, delivery and administration. It has been noted that there are significant risks to staff from noise, manual handling/ergonomic issues and pressure of work and also high levels of sickness absence. (a) Outline the benefits, composition, role and possible functions of an Occupational Health Service within this organisation. (12) (b) What contribution could an Occupational Health specialist make in addressing the risks to staff from stress, manual handling/ ergonomic issues and noise? (8) ANS a The benefits of running an occupational health department within this organisation would include:

Legal compliance (where health surveillance required). Better management of sickness absence (potential financial savings – increased productivity, reduced absence,

reduced claims). Expert contributing to risk assessments. Access to specialist (and perceived as independent) Occupational Health advice.

The composition of the Occupational Health Department would depend on a range of issues (not least of which would be resources available) but might foreseeably include

an occupational health physician (probably part time, e.g. one day a week),

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an occupational health nurse (fulltime), a physiotherapist (or perhaps access to one through a referral scheme), an occupational hygienist (again, part time or access to one); access to trained counsellors (this might be

through a referral system or might involve training for in-house personnel) and perhaps access to an ergonomist (though this might be one of the roles of the occupational health nurse).

Role/function of the department would include training for staff on various occupational health controls; pre-employment screening, health surveillance, record keeping, return to work/fitness assessments, sickness

absence reviews; counselling; testing/monitoring (such as audiometry); immunisation; health promotion.

b) The occupational health department might make some significant contributions to the management of various risks within this workplace. For example, their stress contribution might include

rehabilitation of workers after a period of stress related absence; counselling for staff undergoing psychological stress or trauma (whether work-related or not); risk assessments of high risk occupations or high risk individuals; assessing the adequacy of controls.

The contribution to the manual handling/ergonomic issues might include

risk assessments of manual handling operations or activities involving ergonomic risk (e.g. DSE workstation assessments).

Identifying appropriate control; the assessment of physical ability; eye sight screening; rehabilitation of workers back into work following physical injury or ill-health into at-risk activities.

Their contribution to the management of noise hazards might include

noise risk assessment (including undertaking noise surveys where necessary) and the identification of suitable controls; audiometry of at-risk staff; training for staff on use of controls (e.g. PPE).

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20 Describe, with the aid of diagrams, the features and principles of operation of sampling equipment that could be used to collect the following airborne contaminants for subsequent quantitative analysis in a laboratory:

(a) total inhalable dust; Marks:5 (b) respirable particulate; Marks:5 (c) organic solvent vapour; Marks:5 (d) asbestos fibres. Marks:5

Jan, 2008

54 Personal dust monitoring has been carried out on five workers who all work in the same factory area where dust is released. The five workers were sampled at the same time and for an equal duration. Four of the results were similar but the fifth was significantly higher. Outline the possible reasons for this difference. Marks:10

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70 (a) Outline the principles of a prospective cohort study, as used in epidemiology. Marks:4 (b) National public health monitoring has recorded several hundred cases of an illness. In at least half the cases

the cause has been confirmed, by laboratory tests, as a new strain of virus. Marks:10 Outline the possible data AND data sources that could be used for a prospective cohort study of this outbreak.

(c) Outline factors that may affect the reliability of such cohort studies. Marks:6

Jan, 2010