shopify visitor statistics
SEARCH ALL
Exposure to noise
Exposure to noise

Precis

(Revised 20 November 2017)

Noise is both the reason for part of the industry and its’ greatest risk to health.

The OHS Regulations state that the exposure standard for noise within the workplace has been established as, not exceeding 85dB(A) over an 8 hour working day. Whether you exceed the exposure standard of 85dB(A) Leq depends on the level of noise involved and how long you are exposed to it. The peak noise level of 140dB(C) usually relates to noise that is applied to instantaneous impact or impulse noise such as a gunshot or hammering. Any exposure above the peak is thought to create almost instant damage to hearing.

Within the entertainment industry sound levels in excess of 91dB (A) are quite common and as a result, solutions must be found to reduce workers’ risk of permanent hearing damage.

Consideration must be given to other workers in the shared workplace such as ushers, security and catering staff who may work behind bars or set tables during a sound check.

12.1 Referenced documents:

WHS Regulation 2011

AS/NZS 1269.1:2005 (Occupational noise management—Measurement and assessment of noise immission and exposure).

AS/NZS 1269.3:2005 Occupational noise management – hearing protector program

AS/NZS 1270:2002 Acoustics – hearing protectors

Model Code of Practice: Managing noise and preventing hearing loss at work

Code of practice – Control of noise in the music entertainment industry (2003 Worksafe Western Australia)

12.2 Definitions

 

WHS Regulation Clause 57 Managing risk of hearing loss from noise
(1) A person conducting a business or undertaking at a workplace must
manage, in accordance with Part 3.1, risks to health and safety relating to hearing loss associated with noise.

12.2.1 Decibel (dB)

is the unit for measuring sound levels.

12.2.2 Exposure standard for noise

is defined in the WHS Regulations as an LAeq,8h of 85 dB(A) or an LC,peak of 140 dB(C). There are two parts to the exposure standard for noise because noise can either cause gradual hearing loss over a period of time or be so loud that it causes immediate hearing loss.

12.2.3 LAeq,8h

means the eight hour equivalent continuous A-weighted sound pressure level in decibels, referenced to 20 micropascals, determined in accordance with AS/NZS 1269.1. This is related to the total amount of noise energy a person is exposed to in the course of their working day. It takes account of both the noise level and the length of time the person is exposed to it. An unacceptable risk of hearing loss occurs at LAeq,8h values above 85 dB(A).

12.2.4 LC,peak

means the C-weighted peak sound pressure level in decibels, referenced to 20 micropascals, determined in accordance with AS/NZS 1269.1. It usually relates to loud, sudden noises such as a gunshot or hammering. LC,peak values above 140 dB(C) can cause immediate damage to hearing.

12.2.5 Clause 58 – Audiometric testing

  • This clause applies in relation to a worker who is frequently required by the person conducting the business or undertaking to use personal protective equipment to protect the worker from the risk of hearing loss associated with noise that exceeds the exposure standard for noise.
  • The person conducting the business or undertaking who provides the personal protective equipment as a control measure must provide audiometric testing for the worker:
    1) within 3 months of the worker commencing the work, and
    2) in any event, at least every 2 years.
  • In this clause, audiometric testing means the testing and measurement of the hearing threshold levels of each ear of a person by means of pure tone air conduction threshold tests.

12.3 Exposure to Noise

There is a common misunderstanding in the rock and pop world that Regulations concerning noise levels solely refer to issues of noise pollution and neighbourhood disturbance caused by spill from concert and event venues. However, where people are at work (including the self-employed) then there is a legal obligation for employers, event organisers and the self-employed to control noise levels to protect the health and safety of workers – even if that noise is something deliberately generated and people are willing to expose themselves to potentially damaging levels of noise. The exposure to damaging noise levels is not exclusive to rock and pop, classical musicians are also often exposed to unacceptable noise levels.

Whether the exposure standard of 85 dB(A) averaged over eight hours is exceeded depends on the level of noise involved and how long workers are exposed to it. Peak noise levels greater than 140 dB(C) usually occur with impact or explosive noise such as sledge-hammering or a gun shot. Any exposure above this peak can create almost instant damage to hearing.

Decibels are not like normal numbers. They can’t be added or subtracted in the normal way. The decibel scale is logarithmic. On this scale, an increase of 3 dB therefore represents a doubling or twice as much sound energy. This means that the length of time a worker could be exposed to the noise is reduced by half for every 3 dB increase in noise level if the same noise energy is to be received.

The table below demonstrates the length of time a person without hearing protectors can be exposed before the standard is exceeded.

Exposure Level

dB (A)

Exposure Time Exposure Level

dB(a)

Exposure Time
85 8 hrs 97 30 min
88 4 hrs 100 15 min
91 2 hrs 103 7.5 min
94 1 hr 106 3.8 min

12.3.1 Other effects of noise

Noise at levels that do not damage hearing can have other adverse health effects. This can arise when noise chronically interferes with concentration and communication. Persistent noise stress can increase the risk of fatigue and cardiovascular disorders including high blood pressure and heart disease.

Although safe levels to guard against these effects have not yet been fully determined, as a guide, the risk of adverse health effects can be minimised by keeping noise levels below:

  • 50 dB(A) where work is being carried out that requires high concentration or effortless conversation
  • 70 dB(A) where more routine work is being carried out that requires speed or attentiveness or where it is important to carry on conversations.

12.4 Hearing Protection (PPE)

Personal hearing protectors, such as ear-muffs or ear-plugs, should be used in the following circumstances:

  • when the risks arising from exposure to noise cannot be eliminated or minimised by other more effective control measures,
  • as an interim measure until other control measures are implemented
  • where extra protection is needed above what has been achieved using other noise control measures.

If the use of personal hearing protectors is necessary, it is important that the hearing protectors are worn throughout the period of exposure to noise. Removing personal hearing protectors for even short periods significantly reduces the effective attenuation (noise reduction) and might provide inadequate protection. For example, a worker wearing a hearing protector for a full 8-hour day will receive the 30 dB maximum protection level. However, one hour without wearing the hearing protector causes the maximum protection level to fall to 9 dB.

12.4.1 Personal hearing protectors

Personal hearing protectors should be selected and maintained in accordance with AS/NZS 1269.3 Occupational noise management – hearing protector program. Involve your workers in the selection process and offer a reasonable choice from a range of types.

Suppliers of hearing protectors should provide the full information on the attenuation likely to be provided including the SLC80 ratings, class and octave band attenuation values. The attenuation values should be derived from attenuation measurements made in accordance with AS/NZS 1270 Acoustics – hearing protectors.

12.4.2 Selecting hearing protectors

To select a hearing protector correctly we must first know which workers are exposed, what their exposure levels are and whether or not the hearing protector is compatible with the work environment and other protective equipment use.

A target “in-ear” noise exposure level must be set, e.g. 80 dB(A). Based on the noise exposure levels and the target level, the correct noise reduction of the hearing protector can be determined.

Over-protection (attenuation) must be prevented to avoid feelings of isolation and communication problems leading to inconsistent wearing of the protector in noise. Reduction to below an “in-ear” level of 70 dB(A) should be regarded as over-protection.

The area between 80 and 85 dB(A) could, because of uncertainties introduced by the “real world” ear protection, be regarded as potentially under-protecting.

For good attenuation the “in-ear” noise level should generally be required to fall between 80 and 75 dB(A).

12.4.3 The class method

For this method we only need the 8-hour average value in dB(A) [LAeq,8h], to which the worker is exposed. AS/NZS 1269.3 lists noise level ranges for the five different classes of hearing protectors and their relationship to the above SLC80 rating, in Tables A1 and E1. A combination of Table A1 and E1 is shown below.

Table A1 and E1

AS/NZS 1269.3 Class LAeq,8h dB(A) SLC 80 Range
1 less than 90 10 to 13
2 90 to less than 95 14 to 17
3 95 to less than 100 18 to 21
4 100 to less than 105 22 to 25
5 105 to less than 110 26 or greater

For example, if a worker is exposed to 98 dB(A) as average over the 8-hour shift [LAeq,8h = 98 dB(A)], then a Class 3 hearing protector must be worn by that worker. The SLC80 rating of the hearing protector for the worker therefore must be between 18 and 21.

12.4.4 Noise Reduction Rating (NRR)

The NRR system is used in the USA, but is not acceptable in Australia as the method of testing is different from the AS 1270 test method.

12.5 Risk assessment

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.

12.5.1 Shared responsibility

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 PCBU, 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. Both workers and PCBU must find the balance between what makes our industry work and what is a sustainable work environment.

12.6 External information sources

Unfortunately there is very little useful information available about noise exposure in the entertainment industry. WorkSafe Western Australia commissioned a Code of Practice in 2003, ‘Control of Noise in the Music Entertainment Industry’ (https://www.commerce.wa.gov.au/sites/default/files/atoms/files/code_noise_music_industry.pdf) which contains helpful solutions that may apply in your workplace.

For classical musicians and orchestra staff, the ‘Sound Advice’ report is highly recommended: www.australiacouncil.gov.au/research/wp-content/uploads/2017/06/Sound-Practice-final-report.pdf

 

Detailed guidance on noise in entertainment is available in the UK HSE publication HSG 260 ‘Sound advice: Control of noise at work in music and entertainment’ (http://www.hse.gov.uk/pubns/books/hsg260.htm) and the associated HSE web pages at www.soundadvice.info. ‘Sound Advice’ was produced by a working group of industry stakeholders with support from the Health and Safety Executive. Amongst other things, this guidance contains practical advice on the control of noise in entertainment venues including concert halls, theatres and amplified live music venues.

Please note that the referenced Standards, Codes and legislation only applies to the UK. An Australian addendum of the HSE publication may be considered if there is sufficient interest.