Sound Advice Note 1

Introduction

1.1 Music is perceived as pleasant but can sometimes be loud to produce its effect, while the sound of a jet engine, for example, is regarded as unpleasant. However, both are physically the same thing as far as the ear is concerned. If a sound level is too high or carries on for too long, your hearing may be damaged. This guidance aims to help prevent damage to the hearing of people working in music and entertainment from loud noise, including music.

1.2 The music and entertainment industries are unique in that high noise levels and extremely loud special effects are often regarded as essential elements of an event. High levels of sound are common, for example in bars, nightclubs, orchestras, theatres and recording studios. However, loud sounds, whatever their source, can damage hearing. Hearing damage is permanent, irreversible and causes deafness - hearing aids cannot reverse it. Performers and other workers in music and entertainment are just as likely to have their hearing permanently damaged as workers in other industries.

1.3 Reducing noise risks in music and entertainment is not about destroying art, but about protecting people - artists, performers and ancillary workers equally. The hearing of performers is critical and needs to be protected. There are cases of performers being unable to carry on their profession because of hearing damage as a consequence of their work. With properly implemented measures, the risk from noise in the workplace and the risk of damage to workers' hearing will be reduced.

This Guidance

1.4 The purpose of this guidance is to provide practical advice on developing noise-control strategies in the music and entertainment industries to prevent or minimise the risk of hearing damage from the performance of both live and recorded music. It will also help performers and other workers and employers meet their legal obligations under the Control of Noise at Work Regulations 2005 (the Noise Regulations). It has been produced by a working group of industry stakeholders with the support of the Health and Safety Executive. It supplements the general HSE guidance on the Noise Regulations (L108) Controlling noise at work: The Control of Noise at Work Regulations 2005.

1.5 This guidance will help:

• Venue owners.
• Venue designers and builders.
• Venue operators and managers.
• Musicians, performers and entertainers and their employers.
• Promoters and producers.
• Technical, production, service and support staff and their employers.
• Suppliers of sound equipment.
• Those involved in musical education.
• Anyone whose work may create a noise hazard in the music or entertainment industry.

Risk Assessment

1.6 Risk assessments of the work should identify those people who are likely to be at risk. These will include musicians and performers, technical staff and others working directly on the entertainment, but also may include staff involved in work activities connected to the entertainment, for example ushers, security, front of house, bar and catering staff etc, depending on their location and length of time spent in the noisy environment. A more comprehensive list of people likely to be affected can be found below

1.7 Everyone in the production chain has a role to play in managing the noise risks - whether it is the promoter selecting a balanced line-up, a performer working with reduced monitor levels or stagehands using their earplugs. The main responsibility rests with the employer, but everyone should help reduce noise exposure and take a range of simple steps to protect themselves and others from the hazards of loud noise or lengthy exposure to noise at work.

The Noise Regulations

1.8 The Control of Noise at Work Regulations 2005 (the Noise Regulations) require employers to prevent or reduce risks to health and safety from exposure to noise at work, so far as is reasonably practicable. Employees have duties under the Noise Regulations too. The Regulations specify the minimum requirements for the protection of workers from the risks to their health and safety arising, or likely to arise, from exposure to noise at work.

1.9 The duties in the Noise Regulations are in addition to the general duties set out in the Health and Safety at Work etc Act 1974 (the HSW Act). These general duties extend to the safeguarding of the health and safety, including the risk of hearing damage, of people who are not your employees, such as contractors and members of the public. Employees also have duties under the HSW Act to take care of their own health and safety and that of others whom their work may affect and to co-operate with employers so that they may comply with health and safety legislation. This guidance does not address protection of the public - for more information, look at The event safety guide

1.10 This guidance applies to premises where employees or the self-employed are present, where live (whether amplified or not) or recorded music is being played for entertainment purposes at noise levels which will result in performers' or other workers' daily personal noise exposure being likely to exceed the exposure levels in the Noise Regulations. Anyone whose work may create a noise hazard has a responsibility to themselves and to anyone else who may be affected.

How sound is measured

1.11 Noise is measured in units called decibels, shown as dB. Some sounds, which can be measured, cannot be detected by the human ear. For example, people cannot usually hear bats communicating at very high frequencies or when whales use very low frequencies. To account for the way that the human ear responds to sound of various frequencies a frequency weighting, known as the A-weighting, is commonly applied when measuring noise. The exception is when measuring peak noises, where a C-weighting is applied to ensure that proper account is taken of the sound energy in the peak sound.

1.12 In this guidance all noise levels are given in units of decibels (dB). Unless stated otherwise, readers should assume that values representing average, typical or representative noise levels have been measured using an A-weighting and values representing peak noise with a C-weighting. The terms dB(A) and dB(C) are not used but where noise has been measured using the C-weighting these are referred to as 'peak'.

1.13 Noise can contain many different frequencies. However, when considering ways to control noise, low-frequency noise needs to be treated differently to high-frequency noise. So the division of the A-weighted measurement into its constituent frequencies (frequency analysis) becomes necessary. It is also very important, particularly in music and entertainment, when selecting personal hearing protection, to ensure the correct type for protection from the most damaging frequencies identified during a noise risk assessment. For more information see L108.

Typical noise levels in decibels

Noise action and limit values

1.14 The Noise Regulations require employers to take specific action at certain action values. These relate to:

• the levels of exposure to noise of employees averaged over a working day or week; and
• the maximum noise (peak sound pressure) to which employees are exposed in a working day.

1.15 The values are:

• lower exposure action values (LEAV):
  • daily or weekly exposure of 80 dB;
  • peak sound pressure of 135 dB;
• upper exposure action values (UEAV):
  • daily or weekly exposure of 85 dB;
  • peak sound pressure of 137 dB.

1.16 There are also levels of noise exposure which must not be exceeded (but take account of any reduction in exposure provided by hearing protection):

• exposure limit values (ELV):
  • daily or weekly exposure of 87 dB;
  • peak sound pressure of 140 dB.

1.17 Look at Useful information and glossary for a table of the actions required based on a comparison of exposure action values and exposure limit values.

Noise exposure

1.18 The noise exposure level (often referred to as the 'noise dose') takes account of both the sound pressure level and how long it lasts. Generally the potential for hearing to be damaged by noise is related to the noise 'dose' a person receives. Being exposed to a noise level of 105 dB (a not unusual sound level for a pub band, or that generated by a brass or woodwind instrument at full blast) for 5 minutes would be the same dose as being exposed to 94 dB (a nightclub bar) for 1 hour, or 88 dB (chamber music) for 4 hours.

1.19 Each 3 dB added doubles the sound energy (but this is only just noticeable to a listener). When 10 dB is added, the energy is increased ten-fold, while adding 20dB is a hundred-fold increase. Therefore:

• If the sound intensity is doubled, the noise level increases by 3 dB.
• Two instruments with the same noise level of 85 dB together produce 88 dB.
• A noise level reduction of 3 dB halves the sound pressure level (and its propensity to damage).

1.20 Halving the noise dose can be achieved either by halving the exposure time, or by halving the noise level, which corresponds to a reduction of 3 dB. These noise exposures are identical:

• 80 dB for 8 hours
• 83 dB for 4 hours
• 86 dB for 2 hours
• 89 dB for 1 hour
• 92 dB for 30 minutes

1.21

Average Noise level	Time taken to receive a dose equivalent to the upper exposure action value (85 dB)
85 dB	8 hours
95 dB	45 minutes
100 dB	15 minutes
105 dB	5 minutes
110 dB	Under 2 minutes
115 dB	Under 30 seconds

Exposure when not at work

1.22 It is important that people consider noise exposure when not at work because cumulative exposure leads to hearing damage, whether or not it is work-related. Sound exposure includes all the sounds heard during each day. Common off-hours exposure to high noise levels may include audio and video equipment (personal car stereos, computer speakers, televisions), concerts, clubs and cinemas, sporting events, power tools and noisy hobbies. In general, an employer needs only to consider the work-related noise exposure when deciding what action to take to control risks. However the employer needs to consider whether risk-control measures need to be adapted in certain situations, for example if it is known that an employee is exposed to noise during other employment.

Symptoms of hearing damage

1.23 Hearing loss can be temporary or permanent. People often experience temporary deafness after leaving a noisy place such as a night club or a rock concert. Although hearing recovers within a few hours, this should not be ignored. It is a sign that if you continue to be exposed to high levels of noise your hearing could be permanently damaged. Permanent hearing damage can be caused immediately by sudden, extremely loud, explosive noises such as caused by pyrotechnics. Remember that the hearing of young people can be damaged as easily as the old.

1.24 Hearing loss is usually gradual because of prolonged exposure to noise. It may only be when damage caused by noise over years combines with hearing loss due to ageing that people realise how deaf they have become. This may mean their family complains about the television being too loud, they cannot keep up with conversations in a group, or they have trouble using a telephone. Eventually everything becomes muffled and people find it difficult to catch sounds like 't', 'd', and 's', so they confuse similar words. Musicians may suffer loss of discrimination between tones.

1.25 Hearing loss is not the only problem. People may develop tinnitus, a distressing condition that can lead to disturbed sleep. Other rarer conditions include hyperacusis (a general intolerance or oversensitivity to everyday sounds) and diplacusis (a difference in the perception of sound by the ears, either in frequency or time). Danish research among symphony orchestras suggests more than 27% of musicians suffer hearing loss, with 24% suffering from tinnitus, 25% from hyperacusis, 12% from distortion and 5% from diplacusis. However, there are other studies which give a range of figures from 10-60% for hearing damage among musicians.

1.26 The HSE Noise website provides an audio demonstration of hearing loss. The hearing loss simulations all include the effects of noise exposure and ageing. At the end of each simulation the hearing level undamaged by noise for the age of the person is demonstrated.

Musicians and other workers in the industry

This list is not definitive but indicates the jobs of people working in the music and entertainment sectors that might be affected by loud noise from live or amplified music or special effects.

Glossary

For a more detailed explanation of terms see Useful information and glossary.

Diplacusis: Condition where the two ears hear a given pitch as two distinct tones.

Frequency analysis: The breakdown of sound into discrete component frequencies, measured in Hertz and usually grouped in bands or octaves. Appropriate for selecting suitable hearing protection and designing acoustic control measures.

Hyperacusis: Increased sensitivity to sound which may cause discomfort or physical pain.

Noise exposure: 'The noise dose', which can be calculated, takes account of the actual volume of sound and how long it continues. Noise exposure is not the same as sound level, which is the level of noise measured at a particular moment.

Tinnitus: Buzzing, ringing or tone in the ear. Temporary tinnitus is a warning; a sign that 'you got away with it that time.'

Bibliography