Section B Questions Deck 2

Question 1

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 levels

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. (4)
(b) Outline how you might assess:
(i) the noise level experienced by the rider; (4)
(ii) the level of vibration experienced by the rider. (4)
(c) Outline the range of practical measures that can be taken to reduce the risk of ill-health effects to the driver. (8)

Answer 1

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 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

Question 2

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. (10)
(b) Describe a range of practical measures that the nurses can take to minimise the risk of violence when making visits to patients. (10)

Answer 2

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.
• Violence avoidance measures would include courteous behaviour, diffusing aggression.
• Violence may escalate, so making provision for a quick exit (vehicle parking, exit routes)

Question 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; (4)
(ii) active static sampling; (4)
(iii) active personal sampling. (4)
(b) Outline the strategy to be used in the prevention and control of

exposure to the organic solvents. (8)

Answer 3

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.
b) 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 provide, 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.

Question 4

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. (10)

(b) Outline the content of a training programme that will assist

workers to use the personal protective equipment correctly. (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. (5)

Answer 4

(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 are:

• The chemical resistance to the corrosive solution and the chemical breakthrough time;
• The length of time that the gloves have 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 are:

• 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 meet 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 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.

Question 5

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. (4)

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

In your answer clearly explain the range of technical and

organisational control measures that could be introduced.

Answer 5

(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

Question 6

(a) Identify FIVE workplace sources of ionising radiation. (5)
(b) Outline control measures that should be in place when persons

may be exposed to ionising radiation at work. (15)

(c) Describe the possible health effects from exposure to ionising radiation.

Answer 6

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

(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 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.

(c) 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.

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 fetus.

Question 7

A new health club 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) Identify BOTH the acute AND chronic effects that could result from exposure to UV radiation. (4)
(b) Outline control measures that should be put in place for BOTH workers AND customers for the safe operation of this facility. (12)
(c) Outline TWO other examples of occupational exposure to UV radiation. (4)

Answer 7

a) 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.
b) Control measures that should be put in place both for workers and customers would initially considering

• 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 sunscreen products.
• Other control measures that should be put in place include
  
  • The screening or enclosure of the tanning equipment,
  • The siting of worker workstations away from stray UV radiation,
  • The provision of suitable goggles and ensuring their use,
  • Carrying out regular maintenance on the equipment such as changing tubes,
  • Maintaining records of customer exposure and displaying safety advice to customers.

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.

Question 8

(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)

Answer 8

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);
• 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).

Question 9

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)

Answer 9

(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.

(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.
• Decontamination and training were also relevant.

Question 10

(a) Explain what is meant by the terms ‘carcinogen’ and ‘mutagen’. (4)
(b) 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)

Answer 10

a) a “carcinogen” is a substance that may cause cancer or bring about changes in the makeup of cells while a “mutagen” causes or increases the rate of mutation in DNA and may affect subsequent generations.
b) 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.