Exposure to workplace noise can cause permanent hearing damage and even deafness. Susanna Everton explains how noise is an ideal candidate for workplace health surveillance.
The International Labour Organisation (ILO) defines OH health surveillance as: “The ongoing systematic collection, analysis, interpretation and dissemination of data for the purpose of prevention. Surveillance is essential to the planning, implementation and evaluation of OH programmes and to the control of work-related ill health and injuries, as well as to the protection and promotion of workers’ health. Occupational health surveillance includes workers’ health surveillance and working environment surveillance” (ILO, 1998).
OH surveillance usually takes the form of a periodic clinical screening and/or medical examination of an individual who may be exposed to harmful substances or physical hazards at work that may affect their health. The tests need to be standardised and reproducible. Noise is a physical hazard and hearing loss can be measured, and audiometry is a measurable and reproducible testing procedure – so it is an ideal candidate for health surveillance.
Hearing damage caused by exposure to noise is permanent and incurable. It is usually gradual in onset and can result in deafness when combined with gradual hearing loss in old age.
The Control of Noise at Work Regulations 2005 places duties on employers to assess the risks to their employees from noise at work, take action to reduce the exposure that produces those risks, provide their employees with hearing protection if the noise exposure cannot be reduced, make sure the legal limits are not exceeded and provide employees with information, instruction and training.
Additionally, under reg.9, employees regularly exposed to noise that may damage their hearing are required to take part in health surveillance.
As the ear does not differentiate between noise at work or “at home” – and they can be equally damaging – it would be sensible for individuals to follow the principles of hearing conservation and protection when involved in their hobbies as well as during the working day, where practical.
Identifying the risks
Health surveillance is just one part of a hearing conservation programme. First, you have “to know your enemy”.
What is the noise hazard? Where is it coming from? How long is the individual exposed to it? At what intensity? What can be done to control it? For more information on occupational noise-induced hearing loss, see Occupational health’s role in preventing hearing loss.
Occupational noise exposure is common in the following industries and work activities, among others: those involving firearms and explosives, demolition and building work; forging, pressing and stamping; forestry and logging; music and entertainment; and paper and board manufacturing. It is necessary for anyone managing a noise health surveillance programme to know the business the individuals they are assessing work in so that advice and guidance can be put into context.
With an exposed group of workers having been identified as being at risk through a risk assessment, a health surveillance programme can be set up. This can be provided by suitably trained OH professionals in house, as a visiting mobile unit, or off site at a specialist centre or clinic. However, the management of hearing surveillance and the procedures involved are standard practice and follow guidance to the Regulations.
The procedure for hearing surveillance should be written up and will include reference to the noise risk assessment, the exposed groups of workers and the procedure for using the information.
It is important to engage with employees and their representatives, so that questions and concerns about the programme can be addressed before implementation. This will often help improve employee attendance and participation. The procedure will usually take the following form:
- Identification of at-risk workers from a risk assessment.
- Awareness and instruction for at-risk employees and information for managers:
- briefly outline the risks of noise and the effect on hearing; and
- provide steps to prevent damage at work and during leisure activities – such as the use of ear plugs or defenders when using machinery at home or in the garden, or when attending music or sporting events.
- Carry out baseline hearing health surveillance before the individual is exposed to loud noise, which will involve:
- hearing history and health questionnaire that should include exposures to loud noise, whether in work or in leisure activities, a history of ear infections or conditions and any ototoxic medications taken;
- carrying out an otoscopic examination to see if the canal is clear, the drum is healthy and there is no fluid build-up behind the drum that might prevent sounds from the test being heard clearly; and
- performing an audiometric test – this is usually done using a screening audiometer that is suitable for the work environment; most are automated and produce clear charts and reports – copies of which can be given to the individual – and use software that calculate to Health and Safety Executive (HSE) categorisations.
- Annual review for two years including:
- hearing questionnaire;
- otoscopic examination; and
- audiometric test.
- Three yearly examinations thereafter.
- Issue each individual with “Protect your hearing or lose it!” pocket card or similar that contains notes on good practice for the individual. More frequent testing may be required if significant changes in hearing levels are detected or exposure changes.
Those with changes may be referred for specialist medical examination, and their continuation of “at risk” status will be discussed with the individual, managers, staff and safety representatives.
Just as the employer has a duty to provide health surveillance, the employee has a duty to attend. This must be in work time and at the employer’s expense. If the employee fails to attend or give a valid reason for not attending, disciplinary action may result.
All information on the individual should be kept in two ways.
First, the health record, which will contain personnel details, national insurance number, a brief history of previous and current noise exposures, the health surveillance test performed, date and the outcome (if the employee is declared fit, unfit or referred) and the name and signature of the examiner. This record is not confidential and is held by the manager or employer.
Second, a medical record, which will contain the employee’s details, records of the questionnaire, otoscopic examination, test records and any personal medical information that may have been taken during consultation, and any specialist examination referral. This record is to be kept by the OH professional managing the programme.
The results of the test are summed up across the frequencies one, two, three, four and six kHz and measured against the HSE categorisation scheme for gender and age.
This is a simple way of working out who needs to be referred for further investigation or who may need to be more closely monitored.
Where an individual’s results are showing deterioration in hearing or an unexpected loss, it is important to discuss with the person how the next stage will be managed. It will be necessary to request consent to share the information with the employee’s manager in order to increase protection from further damage, and to make a referral for further examination with the GP or specialist.
The consequences of these examinations may lead to changes in the employees’ work or even be life changing.
Managers and safety representatives can receive individual reports via the health record and can also view a report on the group as a whole, which will contain anonymous data to indicate the effectiveness of any control measures.
This report can inform the manager on the numbers attending for health surveillance, those that did not attend, the range of results and any areas of concern. Records must be kept for 40 years after the last entry.
According to the HSE, analysing the results of health surveillance for groups of workers can give an insight into how well the programme to control noise risks is working. The results can be used to target any noise reduction, education and compliance practices more accurately and should be made available to employee or safety representatives.
Health surveillance is an effective measure of employee ill health when conducted in the appropriate way. It is, however, only a part of occupational health and safety at work, and if other factors indicate controls are not working, then it is important to act immediately and not wait until the health warning becomes a disability.
International Labour Organisation (1998). “Technical and ethical guidelines for workers’ health surveillance”. Geneva.
Everton S (2013). “Occupational health’s role in preventing hearing loss”. Occupational Health; vol.65, issue 3, pp.16-18.
Health and Safety Executive. “Guidance: Control of noise at work”.
Health and Safety Executive. Guidance: Protect your hearing or lose it: HSE pocket guide.