(a) Describe the structure of the skin and how hazardous substances may enter the body by this route. (6)
(b) Explain how contact (primary) dermatitis can occur. (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. (10)
(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.
(b) 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).
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 SDSs, 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 referral for workers with symptoms.
In certain instances, workers with a pre-existing condition may have to be prevented from working with dermatitic agents.
(a) Describe the possible health effects from exposure to ionising radiation. (5)
(b) Outline the control measures that should be in place where persons may be exposed to ionising radiation at work. (15)
(a) the possible health effects from exposure to ionising radiation will include:
- radiation sickness (nausea, vomiting, hair loss),
- dermatitis, a skin irritation. and usually involves itchy, dry skin or a rash.
- burns either superficially to the skin or more penetrating burns causing cell damage, cataracts, temporary or permanent infertility,
- decreased immunity and cancer induction.
(b) 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 using 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.
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).
(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 advise 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) 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 necessitate liaison with the employee’s GP and where necessary arranging for or even providing
counselling and rehabilitation treatment in house. Risk assessments may also need revising.
(b), other ways in which the occupational health department could assist management in improving health and safety in the organisation such as:
- 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.
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. (10)
(b) Outline how the risks to a dentist and those who work with
dentists can be reduced. (10)
(a) the different types of health hazard such as for example:
chemical, biological, and ergonomic, to which members of the dental team might be exposed.
Chemical hazards arise in the use of sterilising agents such as glutaraldehyde, dental materials for example mercury and methyl methacrylate and photographic chemicals used in developing x-rays.
Biological hazards may arise from contact with body fluids and/or clinical waste and from accidental inoculation whilst using sharps
while 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.
Further possible health hazards such as 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) how the risks to the dental team might be reduced.
- The first action would be to complete a risk assessment (identifying the hazards,
- the persons exposed, an evaluation of the risks involved and the control measures that should be introduced).
- 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.
- ensuring adequate facilities were provided for the sterilisation of equipment and the disposal of contaminated sharps;
- introducing controls for the use of x-ray equipment such as time, distance or the provision of barriers;
- introducing policies to deal with the problems of stress and violence.
- providing and wearing suitable personal protective equipment such as overalls, masks and non-latex gloves where these have been found to cause a problem and the provision of training to all members of the
- team in safe working practices such as those connected with manual handling, infection control, ionising radiation and the handling of clinical waste.
A large manufacturing company is to introduce a health promotion
(a) Outline the purpose of a health promotion programme. (2)
(b) Identify issues the health promotion programme should address
AND outline the way in which EACH issue could be promoted. (10)
(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. (8)
(a) the purpose of a health promotion programme is to help workers to improve their own general health and well- being and its intention is to improve the health and well-being of people at work through the combined efforts of employers, workers, and society.
(b) the programme could address:
- the general issue of health awareness by using posters and notice boards to link the promotion with national health awareness days.
- Similarly, the issue of well-being at work could be promoted by offering the possibility of working flexible hours or working from home
- while the subject of healthy eating could be supported by making information available on diet and nutrition and by changing the menu of the works canteen to include the suggested healthy foods.
- Other issues such as smoking, the consumption of alcohol and the need to take exercise could again be promoted by the use of posters, videos and leaflets whilst workers might be encouraged to engage in exercise if membership of a local gymnasium could be arranged at preferential rates.
- other issues such as health monitoring, the benefits of vaccination and/or inoculations, counselling and individual factors such as ageing or pregnancy could be promoted through posters, videos, and arranging wellness days for the particular subject such as pregnancy etc.
- an occupational health physician would be competent to deal with occupational health problems and might refer workers for specialist consultation when this was thought to be necessary
- an occupational hygienist could assist in preventing ill-health from work by anticipating, recognising, evaluating, and helping to control health hazards.
- an ergonomist could assess employees workstations and make recommendations on changing layouts, equipment etc. in order to ergonomically enhance the work environment and thus assist in preventing ill-health.
- a dietician can assess employee diets and make dietary recommendations to employees to promote a healthier lifestyle.
(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
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 bronchioles 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.
- Use of appropriate handling techniques to minimise dust creation when emptying sacks was also relevant.
(a) (i) Identify SIX factors that can affect the thermal comfort of an individual. (6)
(ii) Outline the role of heat indices when assessing a
thermal environment. (3)
(iii) Give an example of a heat index AND identify the
parameters that contribute to this index. (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°C and 5°C.
Describe the control measures that could be used to minimise
the risks associated with working in this cold environment. (8)
- air temperature
- radiant temperature
- air velocity
- metabolic or activity rate
- sweat rate
- duration of exposure
- age, weight, and fitness
- the degree of acclimatisation.
(ii) Heat indices are an objective measure of a thermal environment and provide a single number representation of several different parameters. They give an indication of the severity of a thermal environment and can be used in comparisons to recommend standards as part of a risk assessment.
(iii) an example of a heat index is WBGT (Wet Bulb Globe Temperature) and is measured in degrees Celsius (°C) ,The WBGT unit takes into account environmental factors, such as air temperature, humidity and air movement, which contribute to perception of hotness by people. WBGT values are not the same as humidex values. In some workplace situations, solar load (heat from radiant sources) is also considered in determining the WBGT.
(b) measures such as regular:
- carrying out pre-employment examinations to identify susceptible individuals
- allowing new workers to become gradually acclimatised to the working environment.
- providing thermal clothing such as insulated suits or jackets with gloves, head covering and insulated safety footwear with accommodation and drying facilities for the clothing.
- minimising the amount of effort needed to carry out the work to avoid sweating.
- providing insulated mats for workers to stand on and minimising the amount of time they spend standing or sitting still.
- restricting time spent in the cold store by arranging job rotation and providing hot drinks and a warm rest room.
- introducing precautions to avoid workers being locked in the cold store by ensuring doors can be opened from the inside and by providing alarms.
- carrying out regular health surveillance and providing training and information for the workers on the risks involved in the work and the precautions to be taken.
A company that operates hotels and health spas recognises the risks associated with the legionella bacteria.
(a) In this scenario identify specific sources of potential exposure to legionella for BOTH employees and guests. (5)
(b) Describe the control measures that this company should implement to minimise people being exposed to legionella bacteria. (15)
- water storage and transfer systems (including showers and taps) where the temperature is between 20 and 45 degrees.
- spa baths, saunas, steam rooms and pools
- water features such as fountains and cascades
- fire and garden sprinkler systems
- laundry rooms.
- and pipe work where dead legs exist and stagnation may occur.
(b) control measures that should be implemented are:
- identification of a competent person for overseeing Legionella control;
- regular disinfection of hot water systems with biocides
- annual cleaning and disinfection of calorifiers
- inspection and cleaning of water storage tanks;
- avoiding ‘dead legs’ in transfer pipe work;
- maintaining hot water storage temperatures at temperatures greater than 60 degrees C and cold water below 20 degrees C;
- keeping shower heads and taps clean and free from scale and running showers and taps for several minutes each week in unoccupied rooms;
- running showers and taps immediately prior to occupation of a room;
- treating spa pools continuously with chlorine or biocides and cleaning them on a regular basis;
- avoiding the use in systems of susceptible materials such as wood or rubber;
- Training all relevant employees in risk factors and controls;
- minimising biofilm formation, for example by covering water tanks and the use of chemicals,
- and introducing regular monitoring procedures and record keeping.
Workers can be monitored to estimate their individual exposure to toxic and corrosive substances.
(a) Describe the meaning of the following terms:
(i) toxic; (2)
(ii) corrosive; (2)
(iii) workplace atmospheric monitoring; (3)
(iv) biological monitoring. (3)
(b) Outline the advantages and disadvantages of biological monitoring compared with atmospheric monitoring. (10)
(a) (i) toxic relates to substances that cause harm to living tissue, specifically that at low levels they can cause death or acute or chronic damage to health when inhaled, ingested, or absorbed through the skin
(ii) corrosive substances can rapidly destroy living tissue if inhaled, ingested or splashed on the skin or eyes
(iii) atmospheric monitoring is the monitoring of airborne workplace contaminants, usually by personal sampling though on occasions static monitoring can be used, is based on the inhalation route, and its measurements are averaged over a time scale to give a time-weighted average.
(iv) biological monitoring is a form of health surveillance concerned with the measurement or assessment of hazardous substances or their metabolites in, for example, blood, urine, or expired air to prevent health impairment; and that it takes account of uptake by all routes including skin absorption and ingestion and not only by inhalation.
(b) the advantages and disadvantages of biological monitoring (BM) as opposed to atmospheric monitoring (AM).
advantages of BM are:
- that it measures uptake of a substance by all routes of entry,
- takes account of individual variation when assessing dose,
- and monitors both occupational and non-occupational exposure while AM measures only the atmospheric level.
- BM is particularly relevant where there is a high dependency on personal protective equipment.
Disadvantages of BM are:
- However, there are relatively few techniques and standards available for BM in comparison with the number available for AM.
- BM may involve invasive techniques, can cause confidentially issues, and also may raise ethical issues involved in retrospective monitoring particularly with suspected carcinogens.
- Real-time monitoring is possible with AM but more difficult with BM which is better at pinpointing sources of exposure.
Workers in carpentry workshops and sawmills may be exposed to hardwood dust.
(a) Outline the risks to health from hardwood dust. (5)
(b) Identify types of respiratory protective equipment (RPE) that
could be used by the workers. (3)
(c) Other than providing RPE, outline control measures that should be considered in order to protect those who are exposed to hardwood dust. (12)
(a) Exposure to wood dust has been associated with health issues due to the natural chemicals in the wood, or substances in the wood such as bacteria, moulds, or fungi.
Wood dust is considered carcinogenic to humans (Group 1) according to the International Agency for Research on Cancer (IARC). IARC states that wood dust causes cancer of the nasal cavity (nose area) and paranasal sinuses (spaces in and around the nasal cavity) and of the nasopharynx (upper part of the throat, behind the nose).
Wood dust is also associated with toxic effects, irritation of the eyes, nose and throat, contact dermatitis, sensitisation dermatitis and respiratory system effects which include decreased lung capacity, allergic reactions as well as asthma.
(b) RPE’s that could be used are:
- disposable respirators,
- reusable respirators,
- powered masks and hoods.
- provision of information to workers on the dangers,
- the use of LEV,
- the enclosure of the process
- personal hygiene measures.
- Because wood dust causes asthma any health effects must be picked up early. This can be done using health surveillance, For most woods, low-level health surveillance will do. When someone first starts in a job where they are exposed to wood dust they should fill in a questionnaire. After six weeks they should then complete a follow-up questionnaire and this should then be repeated every year. These questionnaires tell you what to do if you think someone has been affected
- warning signs to designate hazardous areas,
- the setting aside of separate areas for eating,
- vacuum cleaning of machinery/workplace
- and monitoring airborne concentration levels.