Section B Questions Deck 1

Question 1

(a) Identify the typical signs AND symptoms of Legionnaires ‘disease. (5)
(b) Outline the conditions under which legionella bacteria may grow. (3)
(c) Outline the means of controlling the growth of legionella bacteria. (12)

Answer 1

a) The typical signs and symptoms of Legionnaire’s disease include:

• flu symptoms such as fever, chills, shivering, headache, and muscle pain.
• dry cough and breathing difficulties.
• Diarrhoea or vomiting
• confusion and delirium
• ultimately respiratory failure leading to death.

The Incubation period for the disease is between two and ten days.

b) conditions under which legionella bacteria may grow 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 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, where the temperature is between 20 and 45 degrees Celsius.
• 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.

(c) The initial actions to take in order to control the risk of growth 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.
• include identification of a responsible person to manage legionella control
• 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.
• avoiding ‘dead legs’ in transfer pipe work
• keeping shower heads and taps clean and free
• from scale and running showers and taps for several minutes each week
• avoiding the use in systems of susceptible materials such as wood or rubber

Question 2

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 carrying out a noise survey in the open-plan area. (6)
(b) Explain how the noise survey should be carried out AND the type of equipment that could be used to assess workers ‘exposure to noise. (14)

Answer 2

a) The information that 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.
• 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, simple sound level meter for spot checks and integrating sound level meters for the detailed survey, the 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;
  
  • A selection of appropriate sample times over which to measure Leq;
  • 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.
  • 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 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.

Question 3

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. (6)
(b) Outline organisational and personal factors that can contribute to the incidence of work-related stress. (14)

Answer 3

a) Source of information could have included:

• performance appraisal data can be sued.
• 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
• The use of a structured staff questionnaire with the appropriate analysis
• published external guidance and standards
• reports following the investigation of accidents and complaints.
• the rate of staff turnover with the information provided at exit interviews.
• information from informal discussions with workers or with members of management who have been trained in assessing the risk or presence of stress;
• the information gained from surveys and questionnaires
• and that available in external guidance and standards

(b) The factors that could increase the probability of stress occurring:

Organisational factors that may contribute to the incidence of work-related stress include:

• organisational change with the resultant uncertainty and threat of redundancy;
• work overload or conversely under-load;
• unrealistic deadlines or targets which often demand an unreasonable pace to complete the work;
• long work hours and/or difficult shift patterns resulting in a poor standard of work-life balance;
• a lack of consultation with workers on work planning;
• uncertainty over the role or objectives of the job often caused by a lack of training;
• the absence of a system for raising concerns and grievances and even when one is in existence, a failure to address the issues that are raised;
• poor working relationships with managers or colleagues and the presence of bullying, harassment, violence and aggression;
• and a poor working environment, often causing a feeling of isolation from colleagues, whether physical or psychological. To

personal factors such as:

• bereavement, divorce, child care issues and caring responsibilities.

Question 4

(a) Give the meaning of the term ‘ergonomics’. (2)
(b) Outline the effects on health and safety which can arise from poor ergonomic design. (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. (4)
(d) 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 minimise ergonomic risks to their workers when purchasing and then using the laptops. (10)

Answer 4

(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;

(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 in order to prevent eye strain;
• 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 and desk.
• Other factors which would have to be considered would be the involvement of the users in the selection of the equipment;
• revising the DSE and manual handling risk assessments to reflect the new mode of working
• and providing training on the use of the portable machines with reference to carrying out risk assessments on workstations created at home or on the move; on
• minimising the ergonomic risks associated with correct set-up and use, for example on the importance of taking regular breaks and on minimising the manual handling risks associated with carrying the laptop.

Question 5

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. (4)
(b) Outline other factors that should be taken into account when selecting appropriate RPE. (6)
(c) When RPE is used it may not provide the level of protection stated by the manufacturer. Outline the possible reasons for this. (10)

Answer 5

(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 considered 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)?

c) 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.

Question 6

(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. (5)
(b) Outline control measures to minimise the risk of hepatitis B infection. (15)

Answer 6

a) 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.

occupations at risk include amongst others:

• healthcare workers and those involved in the provision of social care and also those involved in the refuse collection or cleaning services.
  (b) Control measures to minimize the risk of hepatitis B infection:
• The use of litter picking sticks to minimize 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 program 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 the importance of ensuring that special precautions are taken by first-aid personnel such as the use of mouth shields.

Question 7

(a) Give the meaning of the following AND give an example:
(i) carcinogen; (2)
(ii) mutagen. (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. (6)

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

Answer 7

a) i) 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.
ii) 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

• 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.

Question 8

A small motor vehicle repair workshop uses paints known to contain isocyanates.

(a) Outline the health effects from exposure to isocyanates. (3)
(b) Outline the factors to consider when assessing the risks arising from using these paints. (7)
(c) Outline the practical measures to control exposure to the isocyanates when spray painting the vehicles in the workshop. (10)

Answer 8

a) 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.
b) The health risks from exposure to these paints 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, type of isocyanates 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 paints 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 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 paints in question have been assigned exposure limits.

If there are multiple exposures to different solvents, then additive effects will need to be considered. 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.

c) In order to reduce employee exposure to the isocyanates there are a range of options that might be considered:

• Eliminate isocyanate from the workplace. This might be done by moving to a totally new production process.
• Substitute the isocyanates for less harmful forms of isocyanate paint, such as MDI or HDI.
• Apply an engineering solution and totally enclose the part of the process where isocyanates 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 apray booth (so that workers who do not need to be exposed are not exposed) should be considered. In this instance, any workers who must come into contact with isocyanates (Paint) must wear PPE which would include appropriate gloves, apron, face protection and respiratory protection.
• Minimisation of the quantities of isocyanates (Paint) being handled is a very practical step.
• Local exhaust ventilation (LEV) must be applied to any enclosures where isocyanates (Paint) is handled/exposed. This LEV must be maintained, cleaned, inspected, and tested.
• Training must be given to all employees on the hazards associated with isocyanates (Paint) and the precautions to follow. This would be particularly important, of course, to the employees who work with the solvent, valuable information can be found on the SDS of the paint.

Question 9

You are a health and safety advisor to a bus operating company. You have been asked to prepare a company policy on drug misuse. Outline key points the policy should include. (20)

Answer 9

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 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.
  
  • The reasons for testing will need to be explained clearly.
  • 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.
  • Confidentiality must be assured.

Question 10

(a) Explain the meaning of the term ‘toxicity’. (2)
(b) Describe the physical characteristics of asbestos and give TWO occupational examples where it is likely to be encountered. (4)
(c) Outline the diseases caused by exposure to asbestos AND their signs and symptoms. (7)
(d) Outline the equipment and method that should be used to determine the level of asbestos fibres in the air in the workplace. (7)

Answer 10

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.