What is the law about high sound levels?
Noise at work in the UK is governed by the Control of Noise at Work Regulations (part of the Health and Safety at Work Act.) The regulations affect employers, employed people, and the self-employed (who count as both). The current UK law came into force on 6 April 2006.
The text of the legislation is on the UK Govenment web site. The HSE has advisory leaflets with basic advice for employers. They also have a comprehensive book Controlling noise at work. Every employer who has staff working in noisy environments should have a copy of this book for reference!
There was a temporary exemption, now expired, for the music and entertainment "sectors" of industry. This allowed them to use previous higher legal limits until April 2008. Guidance to help that industry deal with the current law has been produced by a joint working group of the UK Health and Safety Executive (HSE) and the industry. It's on the Sound Advice web site, and a book is also available.
What are the basic requirements for employers?
If your employees are exposed to loud noise at work, you must make a noise risk assessment of the danger to their hearing. This must be based on evidence, such as measurements of noise in your own premises, or other reliable data. Records of these assessments must be kept. People who assess risk must be competent to do so. In practice this will often mean that they have attended a formal course.
The legislation sets various limits on exposure to noise. If exposure is above any of the limits, you must take certain action, summarised below.
All sound is treated as noise, including speech and music. What must be done depends only on how it measures, not what it sounds like. Sound heard on earphones and headphones also counts, but needs special measurement techniques (see Headphone safety.)
Two types of noise must be measured in different ways:
1. Repeated noise that can gradually, but permanently damage hearing
The noise is added up over a period of time. In the old UK legislation this
was a single day, but now you may average the exposure over a week. That can
make a difference if people are exposed to loud noise on only a few days in the week
(for example, loud music only on Friday and Saturday nights.)
2. Very loud noise that can cause permanent damage immediately.
The highest instantaneous (peak) level of the sound must be measured. Typically, this has to be done when exploding devices such as cartridge operated tools are used, although any very loud percussive sounds might need to be checked.
How loud must the noise be, to make it necessary to take action?
There are three "action values".
The lower exposure action value, is an average of 80 dB (A weighted), measured over a day or a week. This is what you would get by adding up a continuous noise of level 80 dB, over a period of eight hours daily or 40 hours weekly. Alternatively, it is a peak sound pressure level of 135 dB. This average is not very loud! In particular, music at an average level of 80 dB does not, to most people, sound loud enough to damage their hearing.
The upper exposure action value is an average of 85 dB (A weighted). This is what you would get by adding up a continuous noise of level 85 dB, over a period of eight hours daily or 40 hours weekly. Alternatively, it is a peak sound pressure level of 137 dB.
The above values must be measured without protective equipment such as ear muffs or plugs. There are also "exposure limit values" that must not be exceeded, but when estimating these you are allowed to take into account the protection given by protective equipment. These limit values are a daily or weekly average exposure of 87 dB(A weighted) and a peak sound pressure of 140 dB.
To see how noise adds up over a day, check the
If the exposure varies a lot from day to day, to see how noise adds up over a week, check the
OK, so what action might I have to take?
The first action is to keep records of the assessment you have made.
After that, if the assessment shows a risk (based on the measured or properly estimated noise exposure levels given above) then something must be done! It is worth quoting one paragraph of the law in full:
"The employer shall ensure that risk from the exposure of his employees to noise is either eliminated at source or, where this is not reasonably practicable, reduced to as low a level as is reasonably practicable."
This means that you can't just ignore noisy machinery and supply ear plugs; you must make a proper effort to reduce the noise level! The law does make it very clear that supplying ear protection is a last resort, when measures to reduce noise exposure in other ways are impractical.
But if either the lower or upper exposure levels are exceeded, despite efforts to reduce the noise, you must also provide suitable ear protection (after consultation with the employees as to the best type of protection).
You must also provide exposed employees with appropriate instruction and training. The legislation is quite precise as to what must be covered by such training. It could be provided by an in-house safety manager or an external specialist.
If the upper exposure limit is reached, the ear protection provided must be worn. It is up to the employer to enforce this, by disciplinary action if all else fails.In places where employees might be exposed at the upper exposure limit, you must mark "ear protection zones", using the proper sign. Anyone going into an ear protection zone, even briefly, must wear proper protection.
You must also provide health surveillance for those who are identified as being at risk of hearing damage. In practice this means hearing checks. Any employer whose employees are exposed to noise might be very wise to have their employees' hearing checked when they first join the company, so that pre-existing hearing problems can be identified!
What about people who aren't at work, such as audiences?
The legislation discussed here applies only to those at work. You still have to be careful of everybody's hearing under other laws, but the limits are not so strict. For live music and similar events, all aspects of safety are dealt with in the Event Safety Guide. This is available from the HSE bookshop, and it can also be found on-line in various locations - search for "event safety guide".
What about countries other than the UK?
The UK law is based on an EU directive, so the law is similar in all EU countries.
Information about many countries is summarised on a page on this web site: http://staff.washington.edu/rneitzel/index.htm. Noise is added up slightly differently in some countries. The calculators that we provide here use a "3 dB exchange rate" so they are suitable for all EU countries, and many others, but not all.
Don't forget associated hazards!
What are they? Well, for example, will people wearing ear protection be able to hear the fire alarm, or other warnings? The text of the legislation gives a good summary of additional hazards that should be considered.
The information on this page is given in good faith, and I will try to keep it correct and up to date, but it cannot be a complete guide to the law. If you need to know more, I strongly recommended you to contact a specialist. Before doing that, you might like to get some of the very useful guidance published by the HSE. All pages and images on this web site are copyright Tony Woolf 2000 to 2008.