New Noise Exposure Standard
In October 2004, South Australia amended the Occupational Health, Safety and Welfare Regulations 1995, to adopt the Occupational Noise National Standard, consistent with other Australian States and Territories.
To support the standard and provide guidance to workplaces, the National Code of Practice for Noise Management and Protection of Hearing at Work has been approved as a Code of Practice under the Occupational Health, Safety and Welfare Act 1986.
The new exposure standard for noise is:
(a) An eight-hour equivalent continuous A-weighted sound pressure level, LAeq, 8h of 85 dB(A)(previously 90dB(A)); and
(b) A, C-weighted peak sound pressure level, LCpeak of 140 dB(C) (previously Lpeak of 140 dB(lin))
This means that all workplaces must ensure that workers are not exposed to noise levels greater than an average of 85 dB(A) over an eight-hour day or a noise level greater than 140 dB(C) at any instant in time (as measured on the peak setting on a sound level meter).
It is important to understand that this standard should not be considered a safe exposure level, where over a period of time there would be no damage to someone’s hearing or potential for other health effects. Rather, the standard of 85 dB(A) is considered to be an 'acceptable’ risk for the working population.
For instance, research  indicates that after an exposure to of 85 dB(A) over a 40 year working life, 85% of exposed males can expect to experience a 10% loss of hearing while 51% of females can expect to experience an 8% loss of hearing.
The implication for the workers is that, even with the current noise exposure standard a large percentage of the workforce can expect to have incurred significant hearing loss by the time they cease working. Therefore, it is imperative that noise exposure is kept below the exposure standard.
Noise induced hearing loss is also increased by the combined exposure to noise and certain chemical agents (ototoxic substances). For example, organic solvents, carbon monoxide, pesticides and certain metals.
Exposure to noise is also known to cause other health effects, which may occur at levels below the exposure standard, these include; annoyance, interference with concentration and thought processes, stress, reduced immune response, raised blood pressure and acceleration of heart rate.
The Approved Code of Practice provides the minimum requirements for the management of exposure to noise at work, by adopting a risk management approach, that includes, hazard identification, risk assessment and risk control.
Damage to hearing from exposure to loud noise at the workplace is preventable. The risks can be controlled through good management. Where excessive noise may exist, the employer, in consultation with workers and occupational health and safety representatives, must develop a written noise control policy and program of action to implement noise control measures and manage exposure to noise.
SafeWork SA has recently developed a new publication called Noise in the workplace –What you should know, to assist workplaces that may have a noise problem. This publication provides information on noise issues such as health effects, employer and employee responsibilities, legislative requirements and personal hearing protectors. It also includes a Noise Hazard Identification Checklist, which enables workplaces to identify whether or not noise is a problem in their workplace and if there is a need for a detailed noise assessment.
You can download a copy of Noise in the workplace –What you should know from SafeWork SA’s website at www.safework.sa.gov.au The Approved Code of Practice and the new Noise Regulations are also available to download and distribute. Right Click To Download Noise in the workplace - What you should know.
In order to assess the level of compliance with and awareness of the new noise exposure standard and Approved Code of Practice, SafeWork SA will be undertaking an audit program in a range of industries in 2006.
 Information from the "Australian Standard AS/NZS 1269.4 Occupational noise management, Part 4 Auditory assessment"
If you require further information please contact:
Dr Joe Crea
Chief Advisor - Occupational Hygiene
Telephone: (08) 8303 0207
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