Your Work and Your Health
Noise - the employers' perspective
Frequently Asked Questions
- What is noise?
- Do I need to understand noise?
- Why should I be concerned about noise?
- How will I know if noise is harmful in my workplace?
- Do I have a legal duty to protect my workers' hearing?
- When do I have to protect my workers' hearing?
- Do I need to provide training for my workers?
- Where can I get help and advice?
What is noise?
In work situations noise is defined as unwanted sound - an undesirable
by-product of our normal day-to-day activities, for example aircraft,
traffic, music, and machinery noise. There is a risk that your hearing
may be damaged when you are exposed to noise, which may result in temporary
and/or permanent deafness.
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Do I need to understand noise?
You do not need to have an in-depth understanding of noise in order to
be able to protect your workers from the potentially damaging effects
of noise. However it would be useful for you to know some of the common
terms used for describing noise in the workplace.
Mechanical movements from for example fans, power tools and vehicles,
set up fluctuations in the air pressure. These travel as sound waves through
the air, spreading out just like ripples in water when a stone is dropped
into a still pond. The frequency of the sound is the number of
fluctuations per second, expressed as hertz (Hz). The frequency of a sound
produces its distinctive tone; the rumble of distant thunder has a low
frequency, while a whistle has a high frequency.
Sound is measured in decibels (dB). The ear does not hear all frequencies
equally. It is most sensitive to sounds between 2 kHz and 5 kHz, and less
sensitive at higher and lower frequencies. Noise measurements are often A-weighted to reflect how the ear responds to noise. They are expressed
in units of dB(A). Some typical dB(A) levels are given below:
- normal conversation 65 dB(A)
- lathe 80 dB(A)
- train passing 100 m away 85 dB(A)
- road breaker 95 dB(A)
- grinding 110 dB(A)
Back to the top Why should I be concerned about Noise?
As an employer, you have duties under the Noise at Work Regulations 1989
to manage the risk to your workers' hearing if they are exposed to noise
at work because it could damage their hearing.
Initial exposure to high levels of noise may result in temporary deafness
- ie temporary threshold shift. Although hearing can recover within a
few hours it is a sign that continued exposure to noise at this level
could cause permanent hearing damage. Unfortunately, by the time that
such hearing loss is apparent, the damage to hearing is generally considerable
and can't be cured.
Permanent hearing damage can also occur immediately following exposure
to sudden, extremely high explosive noises, for example from guns or cartridge-operated
tools. Workers could also suffer from tinnitus following exposure to these
sudden loud noises.
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How will I know if noise is harmful in my workplace?
Certain types of work are known to be associated with high levels of
noise, for example engineering workshops, sawmills, foundries, bottling
plants, clubs, textile mills, farming, forestry, or construction. Your
workers' hearing could also be at risk if they are involved in these types
of work.
Your workers' hearing could be at risk if:
- they have to shout to be clearly heard by someone 2 m away;
- their ears are still ringing after leaving work;
- they use equipment that causes loud explosive noises such as guns or cartridge-operated tools.
Back to the top Do I have a legal duty to protect my workers' hearing?
Yes! You have a legal duty under the Noise at Work Regulations 1989 to
assess and where required reduce the risk of injury to the hearing of
your workers. You therefore need to be aware of the requirements of these
regulations.
The Health and Safety Executive (HSE) has produced guidance that will
help you understand your duties under the noise regulations. It includes
information on:
- the effects of exposure to noise;
- your legal duties to protect your workers' hearing;
- how to assess and control the noise;
- how to choose quieter equipment and machinery;
- different methods of hearing protection;
- health surveillance (hearing checks).
This guidance is freely available at http://www.hse.gov.uk/pubns/indg362.pdf. You can also obtain a free copy by calling the HSE Infoline on 08701 545 500.
Back to the top When do I have to protect my workers' hearing?
Your duties under the noise regulations apply when your workers' noise
exposure is likely to be at or above any of following three action levels:
- First action level - daily personal noise exposure of 85 dB(A)
- Second action level - daily personal noise exposure of 90 dB(A)
- Peak action level - maximum pressure 200 Pascals (140 dB(C))
The peak action level relates to the maximum pressure reached by a single noise, for example the noise from power press, drop forge, firing of explosives or firearms. If this type of noise is likely to occur in your workplace, you need to ensure your workers are protected. Methods for selecting appropriate hearing protection is covered in HSE guidance "Reducing Noise at Work: Guidance on the Noise at Work Regulations 1989 - L108" which is available from HSE Books and good booksellers.
If you have access to the internet, there is a noise exposure calculator on the HSE website. You can use this to help you work out the overall daily noise exposures of your workers. It is available at http://www.hse.gov.uk/noise/calculator.htm. The calculator is easy to use as long as you know the noise levels your workers are exposed to - you will get this information from a noise assessment - and the amount of time your workers are exposed at these particular levels.
If you do not have immediate access to the noise levels your workers are exposed to, you could contact tool and machinery manufacturers and suppliers. They may be able to give you reliable information on the noise levels that could be produced by their products, which could be used to estimate your workers' likely noise exposure. However in due course you would need to verify your estimate since using manufacturer's data for assessment purposes may underestimate or overestimate your workers' daily personal noise exposure.
You should be aware that the UK is introducing new noise regulations in early 2006. In the new regulations, you will have to take action to protect your workers' hearing at lower exposure values. Information on the new regulations is available at http://www.hse.gov.uk/noise/issues.htm or you can call the HSE Infoline on 08701 545 500 for an information pack.
Back to the top Do I need to provide training for my workers?
If your workers are exposed to noise above any of the action levels,
you need to provide information, instruction and training on what measures
you have put in place to control the risk of damage to their hearing.
This should include information on the level of risk to your workers'
hearing as identified by the noise assessment, what measures you have
put in place to control that risk, training to all the workers on the
control measures including the use and maintenance of hearing protection,
and the duties your workers have under the noise regulations.
If you do not have the skills or knowledge, or access to them from people
within your workforce, to implement the requirements of the noise regulations
you will need to go outside the company for advice. In the longer term
you may want to organise some training for yourself or your workers, so
that you have access to the necessary skills and knowledge in-house.
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Where can I get help and advice?
There are many sources of help and advice available to you covering noise
assessments, calculating noise exposure and noise control. Examples of
where this advice can be found include HSE, trade associations and trade
unions. If you have access to the internet, HSE has a webpage for noise
at http://www.hse.gov.uk/noise.
You can also obtain information on noise by calling the HSE Infoline on
08701 545 500.
A variety of training courses are available to help you gain the necessary
skills and knowledge to carry out your duties under the noise regulations.
Alternatively you use consultants who already have the necessary training
and experience to help you carry out your legal duties. Contact details
for training courses and consultants are given below:
Institute of Acoustics
77A St Peter's Street, St Albans, Hertfordshire, AL1 3BN
Tel: 01727 848195
Email: ioa@ioa.org.uk
Web: www.ioa.org.uk
National Examination Board in Occupational Safety and Health (NEBOSH)
Dominus Way, Meridian Business Park, Leicester, LE19 1QW
Tel: 0116 263 4700
Email: info@nebosh.org.uk
Web: www.nebosh.org.uk
British Occupational Hygiene Society (BOHS)
Faculty of Occupational Hygiene, Suite 2, Georgian House, Great Northern
Road, Derby, DE1 1LT
Tel: 01332 298101
Email: admin@bohs.org
Web: www.bohs.org
Association of Noise Consultants
6 Trap Road, Guilden Morden, Royston, Hertfordshire, SG8 0JE
Tel: 01763 852958
Email: mail@association-of-noise-consultants.co.uk
Web: www.association-of-noise-consultants.co.uk
This site is supported by the Healthy Work Matters Group