Sound Advice Note 3

Risk assessments for noise

3.1 The aim of a noise risk assessment is to help decide what measures are necessary to ensure the health and safety of employees who are exposed to noise. It is more than just taking measurements of noise - sometimes measurements may not even be necessary. But it needs to be drawn up by someone who is competent to carry out the task and be based on advice and information from people who are competent to provide it. This could be someone from within the organisation. Noise risk assessments should:

• identify where there may be a risk from noise and who is likely to be affected;
• contain a reliable estimate of the noise exposure and compare this with the exposure action and limit values;
• identify what noise-control measures are needed and whether hearing protection is needed and, if so, where and what type;
• identify any employees who need to be provided with health surveillance and whether any are at particular risk.

Is it too noisy?

3.2 In many cases it should be possible to come to a decision quite quickly using what is known about the work going on, or by making simple observations. Other parts of this guidance provide information to help identify those people in specific sections of the music and entertainment industry who are likely to be at risk from the playing of live or recorded music.

3.3 The following 'listening checks' may be useful in deciding whether there are likely to be noise risks. As a simple guide you will probably need to do something about the noise if any of the following apply:

• Does the work involve lengthy exposure to music either live or recorded, for example, pubs, clubs, live music venues, orchestras, or using headphones?
• Is the noise intrusive - similar to the noise from a busy street - for most of the working day?
• Do people have to raise their voices to carry out a normal conversation when about 2 m apart for at least part of the working day?
• Are noisy tools used, such as during rigging, for more than half an hour a day?
• Are there any loud effects such as pyrotechnics or maroons?

3.4 Even extremely short exposure to very loud noise is dangerous. Some percussive or explosive sounds last for a very short time, but are at such a level that hearing damage can occur. Exposure to such noises is uncommon in the normal environment, however pyrotechnics, fireworks and even loud sound systems can deliver peak noise levels in excess of the 140 dB exposure limit value set by the Noise Regulations.

3.5 Sounds peaking above 140 dB are liable to cause immediate and lasting damage rather than accumulating over time. It is therefore crucial that a thorough noise-control strategy is in place before any exposure to loud noise might occur.

Who might be harmed, and how?

3.6 All employees who are likely to be affected by the noise should be identified. Consider not just people who are exposed to noise in relatively fixed locations, but also people who move between different jobs or types of work, and make sure you understand their patterns of noise exposure. Remember to include people who are not direct employees but who may be affected by the work, for example visitors or subcontractors.

3.7 In considering the potential for people to be harmed, it is mainly necessary to think about hearing damage. But it is also necessary to consider risks to safety which can arise from working in a noisy environment, such as noise interfering with communications or warning signals and the ability to pick up audible signs of danger.

Estimate the noise exposure

3.8 The daily personal noise exposure (LEP,d) of workers at risk should be estimated and compared with the exposure action and limit values. It takes account of both the level of the sound and how long it lasts. Often a worker's daily noise exposure is made up of a number of periods of time exposed to different levels of noise, so this needs to be taken into account when estimating exposure.

3.9 It is essential that any estimate of employees' exposure is representative of the work that they do. It should take account of:

• the work they do or are likely to do;
• the ways in which they do the work;
• how the work may vary during the day or from one day to the next.

3.10 The estimates of the noise levels must be reliable enough to be able to assess whether any exposure action values are likely to be exceeded. Reliable information may include:

• noise measurements in the actual work situations;
• information from other similar work situations;
• information from other sources, for example information on typical noise levels and noise exposures which may be helpful.

3.11 Tools are available on the HSE website (www.hse.gov.uk/noise/calculator.htm) that allow noise exposure to be calculated based on information on likely noise levels and durations of exposure. There is a noise ready-reckoner chart (see also page 13) and an electronic spreadsheet.

3.12 When in any doubt, assume that control measures are necessary and that hearing protection will be required until the control measures are sufficient to reduce the employees' exposure to below the upper exposure action value. If music is to be played (especially loud amplified music) it would be good practice to assume there is a risk and some noise controls will be necessary.

Weekly exposure

3.13 Where noise exposure varies markedly from day to day, the weekly noise exposure level may be used as an indicator of risk. It is only likely to be appropriate to use weekly exposure where:

• daily exposure on one or two working days in a week is at least 5 dB higher than the other days; or
• the working week comprises three or fewer days of exposure.

3.14 Using weekly exposure to indicate risk should not lead to the lowering of standards of protection on days where noise exposure is higher. Workers and their safety or employee representatives should be consulted on whether the use of weekly exposure is appropriate.

3.15 Tools are available on the HSE website that allow weekly noise exposure to be calculated based on information on levels of daily noise exposure. There is a noise ready-reckoner chart and an electronic spreadsheet.

3.16 Consult safety representatives about risk assessments along with any control measures. Where there is no formal representation, employers should liaise with the local Musicians' Union and Equity representatives or employee representative groups. Also tell staff about the significant findings of the risk assessment.

Identify what needs to be done to control the risks

3.17 An essential outcome of the noise risk assessment is to control the risks. In carrying out a noise risk assessment employers should:

• identify who is at risk and under what circumstances, and assess likely exposures. This allows prioritisation and planning of control actions;
• be aware of current good practice or the standard for noise exposure control within the relevant part of the music and entertainment sector, considering whether the control measures are applicable to their work and adopting them where it is reasonably practicable to do so;
• consider the advice on noise control-measures for sections of the music and entertainment industry in other parts of this guidance;
• record the significant findings of the risk assessment. Record in an action plan anything identified as being necessary to comply with the law;
• prepare an action plan setting out what has been done and what is planned, with a timetable. Say who will be responsible for the work and how this is to be communicated to those affected.

3.18 The action plan, as well as covering any ways of organising the work or technical measures needed to eliminate risks from noise or reduce noise exposure, should also cover issues such as:

• providing personal hearing protection to workers to deal with immediate and ongoing risks;
• arrangements for providing information, instruction and training; and
• health surveillance for workers.

3.19 In developing an action plan for noise, employers should consider what management arrangements are needed to ensure that the control measures put in place are working and being followed in practice. Consider also how to adapt or modify the control measures, for example where a music event may be undertaken in different venues, where differences are anticipated between rehearsal and performance, or where changes to the layout of the working environment are likely which could affect the risks from noise exposure.

Regular monitoring

3.20 Risk assessment is an ongoing process and regular checks are essential to make sure the control measures continue to be effective. This may also identify any further actions necessary. Any incidents, for example where it is found that control measures are ineffective or not being used or followed, should be investigated to find out why, and action taken. Record the results of monitoring.

Reference positions

3.21 Specific noise measurements conducted in the workplace can help identify the main sources of noise and make it easier to assess where further controls are necessary and when periods of wearing compulsory hearing protection are required.

3.22 It may be helpful to have one or two sound-level meters or noise dosemeters to estimate noise exposures, for example within the orchestra/band or on the dance floor. It may also be useful to establish reference position(s) to enable quick measurements to be made using a simple meter to verify that sound levels are under control.

3.23 This information can be recorded and compared with the assessment, and any relevant findings can be applied to future assessments. Examples of locations for reference positions are included in Sound Advice Note 10 Rock and pop, Sound Advice Note 11 Pubs and clubs and Sound Advice Note 12 Orchestras.

Review risk assessments

3.24 The noise risk assessment should be reviewed regularly. There are various reasons why this should happen, including:

• there is any reason to think that the risk assessment does not reflect the current noise risks, for example changed working methods or different work patterns such as changes to the set, design or seating layout;
• health surveillance shows that workers' hearing is being damaged;
• control measures that could not be justified when originally considered (for example, on cost or practicability grounds) become reasonably practicable due to some changed circumstances.

3.25 Even if it appears that nothing has changed, the risk assessment should not be left for more than about two years without checking whether a review is needed.

3.26 A flowchart summarising the process of noise risk assessment is shown below.

Planning

3.27 Every event needs to be properly planned, to ensure that health and safety requirements are fully considered. The degree of planning will vary according to the complexity of the event but every event will benefit, whether it is a pop concert, a gig in a pub, an orchestral concert or a club with a guest DJ. Larger venues may have a specific policy statement which may help with planning (see Sound Advice Note 8 Venues).

3.28 Start to assess the likely noise levels as soon as possible to identify any potential noise risks. This is best done well before any music is played in rehearsal or performance. The employer, or the principal employer, for example the promoter or pub landlord, should decide whether the proposed event might lead to high noise exposure levels for those working there and what controls might be necessary. They should record and retain these results as part of their noise risk assessment.

3.29 Where appropriate consider:

• the nature of the event and music
• the site/venue layout;
• the likely noise footprint/map (the area covered by the sound);
• where there may be a risk from noise and who will be affected;
• expected sound levels and expected durations;
• selection of loudspeaker types and other equipment;
• suitable control measures available for noise hazards;
• the need to allow for sufficient rehearsal time to identify and control any unforeseen risks before harm is caused.

Communications

3.30 Good communications are essential for good planning. The assessment process should involve the exchange of information between people who may be affected by the event, for example, promoters, venue operators, contractors, local authorities and recording companies. This should start at the earliest opportunity and continue. In the case of 'rock and pop' acts, wherever possible the performers should be involved in the planning process and become an integral part of the noise management plan.

3.31 Event organisers should ensure that everybody involved in planning an event is competent and capable of carrying out their duties. There may be a need to provide specific training for technicians and managers.

Recovery periods

3.32 When planning events, allow time for a person's ears to recover from exposure to loud noise. The time required to recover fully from the temporary effects of noise is related to the level of noise and the duration of exposure. Musicians who have played at an evening performance need recovery time before rehearsing the following morning. As a practical rule higher levels of noise during the rest period may impede the recovery of hearing and might lead to permanent damage.

Multiple employers

3.33 Where there are several employers, all the employers involved should agree at the earliest possible opportunity which employer is to co-ordinate the measures necessary to comply with the Noise Regulations. (This will usually be the employer responsible for co-ordinating other health and safety responsibilities and is usually the person in overall control of the work.) This person should make sure that the responsibilities for controlling risks are clearly defined. Where contractors and sub-contractors are involved it is usually best for responsibilities to be set out in the contractual arrangements (see Contracts in Sound Advice Note 2 Responsibilities).

3.34 Where there is an established safety committee they should be consulted on how best to develop the management and monitoring of noise exposure. Employers may wish to consider other methods that have been adopted such as noise committees. Specific input might come from people such as responsible managers, players, conductors, safety and occupational health and safety advisers, and representatives from frequently visited venues. Where amplified sound is used, people such as sound designers, sound engineers, sound contractors and production managers should also be involved.

3.35 Any group, or its members, should have enough authority to implement the necessary controls or protective measures, including long-range planning and venue alterations etc. A group will probably operate in different formations for different purposes - for example, the grouping needed to consider the noise implications of long-range planning decisions may differ from that finishing the arrangements for that night's concert.

Policy statements

3.36 A written statement of venue policy is a good way of communicating controls to those working in or using the venue. The policy may include:

• Communication of the risk to hearing from the noise.
• The mechanism for the noise risk assessment, which may include noise measurements.
• A description of the measures established to control the risk. For example the specification of maximum permissible noise levels through physical regulation of the volume or by means of automatic noise limiters (see Sound Advice Note 4 Noise-control measures and training)
• Hearing protection policy - the specification of suitable hearing protectors and where they are available (see Sound Advice Note 5 Personal hearing protection).
• Procedures for monitoring and review.

Touring

3.37 Pre-planning is especially important when taking a production or band on tour:

• Carry out a generic assessment of likely noise risks and who will be exposed before the start of the tour and identify controls. Review this assessment at each venue to ensure the controls are still suitable.
• Review these risk assessments when circumstances change. For example, the maximum permitted number of players in each orchestra pit might vary in different theatres and this may affect noise exposure.
• Venue managers, tour managers and others involved should share their risk assessments to identify the most suitable controls for the event or performance.
• Control measures identified before touring should be reviewed on site (at each touring location) to ensure they are adequate.

Working elsewhere in the EU

3.38 The European Directive on which the Noise Regulations are based (Directive 2003/10/EC) sets down minimum standards for the control of noise at work throughout the European Union. Individual EU countries may have additional requirements.

Working outside the EU

3.39 Outside the EU, local requirements might not correspond to EU requirements. Those working outside the EU are recommended to clarify the position. Those employed in the UK who are touring are advised, where necessary, to negotiate for the maintenance of health and safety standards equivalent to those of the EU to be included in their contracts of employment. For those employed outside the EU it is advisable to clarify the health and safety standards that will apply and seek to get the safeguards required to protect their hearing.

3A1 - Estimating noise exposure using the points system

Noise exposure ready-reckoner

Sound pressure level, LAeq (dB)	Duration of exposure (hours)
	1/4	1/2	1	2	4	8	10	12
105	320	625	1250
100	100	200	400	800
97	50	100	200	400	800
95	32	65	125	250	500	1000
94	25	50	100	200	400	800
93	20	40	80	160	320	630
92	16	32	65	125	250	500	625
91	12	25	50	100	200	400	500	600
90	10	20	40	80	160	320	400	470
89	8	16	32	65	130	250	310	380
88	6	12	25	50	100	200	250	300
87	5	10	20	40	80	160	200	240
86	4	8	16	32	65	130	160	190
85		6	12	25	50	100	125	150
84		5	10	20	40	80	100	120
83		4	8	16	32	65	80	95
82			6	12	25	50	65	75
81			5	10	20	40	50	60
80			4	8	16	32	40	48
79				6	13	25	32	38
78				5	10	20	25	30
75					5	10	13	15

Total exposure points (EP)	Noise exposure LEP,d (dB)
3200	100
1600	97
1000	95
800	94
630	93
500	92
400	91
320	90
250	89
200	88
160	87
130	86
100	85
80	84
65	83
50	82
40	81
32	80
25	79
20	78
16	77

Instructions:

• For each task or period of noise exposure in the working day look up in the table on the left the exposure points corresponding to the sound pressure level and duration (e.g. exposure to 93 dB for 1 hour gives 80 exposure points);
• Add up the points for each task or period to give total exposure points for the day;
• Look up in the table on the right the total exposure points to find the corresponding daily noise exposure (e.g. a total exposure points for the day of 280 points gives a daily noise exposure of between 89 and 90 dB)

Example one: Bar staff

1. Employees in a nightclub have a typical work pattern. They work for a total of 6 hours in the nightclub from 20:00 to 02:00 the following morning. During this shift they work:
   • behind a bar for 2 hours where the noise level is 90 dB;
   • collecting glasses for 2 hours where the noise level is 94 dB;
   • working in the cloakroom for 90 minutes where the noise level, determined using a simple listening test, suggests a level of approximately 80 dB;
   • in the staff room for 30 minutes where the noise level, determined using a simple listening test, suggests a level of approximately 80 dB.
2. The calculation of the noise exposure is shown below, based on the noise exposure ready-reckoner at www.hse.gov.uk/noise/calculator.htm:

   Noise level	Duration	Notes	Exposure points
   90 dB	2 hours	2 hour column and 90 dB row	80
   94 dB	2 hours	2 hour column and 94 dB row	200
   80 dB	2 hours	The exposure in the cloakroom and staff room are added to give a total of 2 hours	8
   Total noise exposure points			288
   LEP,d			89 to 90 dB

3. This work pattern of noise exposure gives a daily exposure (L_EP,d ) of between 89 and 90 dB. The priority for noise control or risk reduction is the noise exposure while working behind the bar and while collecting glasses, as these give the highest individual noise exposure points.

4. Example two: Weekly averaging using the HSE on-line calculator

   Steve is a sound engineer who does an average of two shows a week. The remainder of his time is spent preparing and servicing equipment, paperwork and travel. Assessing his overall noise exposure on the basis of a single day's measurement would not be representative - it would either be too high on a show day, or too low on a warehouse day. The HSE website has both daily and weekly noise exposure calculators that allow input of sample measurements to give an average overall weekly exposure.
5. An average show day would include:

   Activity	Duration	Noise level (LAeq)
   Travel to show	45 minutes	75 dB
   Load-in and installation	2.5 hours	72 dB
   System check	15 minutes	89 dB
   Sound check	30 minutes	92 dB
   Show	2.5 hours (inc. support act)	96 dB
   Load-out and travel	1.5 hours	73 dB

6. Inputting these values into the daily exposure noise calculator gives an average personal exposure of 91 dB and an exposure point value of 436. Note the insignificance of the set-up and travel periods compared to overall exposure.
   
7. For Steve, non-show days are usually of two types; office or warehouse. Office days present negligible noise exposure and the daily exposure is below 70 dB.
8. Warehouse days are a bit more variable and may include running sound systems to check components, using a compressor for spray painting and so on. If the same daily exposure process is adopted for a representative warehouse day, this gives the figures below.

   Activity	Duration	Noise level (LAeq)
   Stock check and equipment preparation	3.5 hours	68 dB
   Loading/unloading vehicles	1.5 hours	78 dB
   System operation check	15 minutes	92 dB
   General admin and office	2.75 hours	65 dB
   Use of spray booth	30 minutes	83 dB

9. Inputting these values into the daily exposure noise calculator gives an average personal exposure of 79 dB and an exposure point value of 25.
10. To establish a representative weekly exposure, take these three exposure patterns and add them into the weekly exposure calculator. Steve does two shows and two warehouse days a week, and one office-only day.
11. Inputting these values into the weekly exposure noise calculator gives an average personal exposure of 87 dB.
12. The results show that even with two relatively quiet warehouse days and one 'very quiet' office-only day, Steve's exposure is 87 dB; this is above the upper exposure action value. The dose he receives on show days is the most significant.
13. For a freelance musician example see Sound Advice Note 7 Freelancers.

3A2 - Measuring noise

1. This Appendix gives a brief overview of the techniques used to measure noise. It is aimed at providing supporting information rather than as a guide to competency. Fuller information can be found in L108. Noise measurements should be carried out by someone who is 'competent', with the relevant skills, knowledge and experience to undertake measurements in the particular working environment. Noise-measuring equipment generally involves the use of a meter incorporating a microphone and a method of recording the noise levels. The exact type and how it is used will depend on what is being measured and why.

2. Establishing personal noise exposure

   Determining personal noise exposure depends on knowing the noise levels that a person is exposed to, and how long they are exposed to these levels. When making noise measurements the aim is to establish the noise at the position occupied by the head of the person whose exposure is being evaluated.

3. Hand-held sound-level meters

   One method is the use of a hand-held sound-level meter. This is most suited to making sample noise measurements at the position of a person's head. Where noise sources are distinct and close to the subject, such as playing of musical instruments, it is particularly important to choose an appropriate measurement position. Where the measurement is made at the side of a person's head, it should be made on the side where noise levels are higher. Where a person is working in an area with a broader diffuse noise source then the measuring position is not so critical, as it is the noise level in the area into which the person is entering that is being measured, such as an area in front of a stage at an outdoor event. In this case taking an average noise measurement over the area may be appropriate.

4. Personal dosemeters

   Another method is the use of dosemeters. These have the advantage of being able to measure noise over prolonged periods of time, even the full working day. Various types are in use but all of them will have a microphone that can be mounted on the shoulder, to make a representative measurement of noise at the head position. The microphone should be placed on the side of the head most exposed to noise. Elevated noise levels will be recorded where dosemeters are mistreated. They can be prone to errors by accidentally knocking, rubbing or covering the microphone, so employers need to be sure that the levels recorded reflect the working conditions. They often allow a visual record of noise levels over time to be produced, so can help to understand the dominant sources of noise exposure for people who are exposed to various noise sources during the day.

5. Fixed monitoring

   This is often used by employers to monitor noise levels in a specific area where previous investigations have established a level that should not be exceeded. A microphone will be installed at a point that has been identified as being important for monitoring and the information relayed to a metering point that can be seen by a duty manager. This is useful in clubs and pubs where bands bring in their own equipment. Noise limiters with feedback systems (see Sound Advice Note 11 Pubs and clubs) are a variation on this theme.

Glossary

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

Competent: Having such practical and theoretical knowledge and such experience as is necessary to carry out the work (see Useful information and glossary).

Exposure action values: Levels of exposure to noise at which certain actions need to be taken (see Useful information and glossary).

Exposure limit value: These relate to personal exposure to noise and must not be exceeded (see Useful information and glossary).

Musicians Union: 60-62 Clapham Road, London SW9 0JJ. 020 7582 5566 www.musiciansunion.org.uk.

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 a sound level, which is the level of noise measured at a particular moment.

Noise limiters: Sometimes known as volume regulatory device (VRD), controls noise exposure from amplified music. Modern noise limiters can be fitted with anti-tamper relays connected to external switches to improve system security.

Noise measurements: Decibels (dB) are used for measuring noise. A-weighting is used to approximate to the frequency responses of the human ear. C-weighting is used to measure peak, impact or explosive noise.

Reference position:Standard location, usually static, selected to enable monitoring of noise levels to be conducted by measurements. (see Sound Advice Note 4 Noise control measures and training).

Bibliography