OHS Newsletter – November 2012 – Noise in the Workplace
LISTEN UP!! – Let’s Talk Noise in the Workplace
Occupational noise-induced hearing loss is caused by exposure to excessive noise at work. The degree of hearing loss increases with the length of exposure and the level of noise. It is almost entirely preventable but, once acquired, the damage is mostly irreversible.
In NSW, the number of claims for Occupational Diseases is increasing and the average cost is double the cost of a workplace injury. Between 2007 and 2010, noise-induced hearing loss accounted for over 9400 claims at an average cost of more than $46,600. (Reference – NSW Occupational Disease and Wellbeing Strategy 2011-2015)
Managing the risk of noise in your workplace
Hazardous noise can destroy the ability to hear clearly and can also make it more difficult to hear sounds necessary for working safely, such as warning signals, instructions etc. Damage to hearing generally occurs gradually over a number of years. It is often an irreversible condition that can have a terrible impact on a person’s life. Hearing can also be damaged immediately by exposure to impulse noise such as from explosive powered nail guns, firearms, stamping presses and forges (known as acoustic trauma). The hair cells in the inner ear are destroyed by loud noise. Once they are destroyed they do not grow back.
Health and Safety Duties in relation to Noise
A PCBU has the primary duty under the WHS Act to ensure, so far as is reasonably practicable, that workers and other are not exposed to health and safety risk arising from the business or undertaking. The WHS Regulations details more specific obligations for PCBUs to manage the risks of hearing loss associated with noise at the workplace, including:
– ensuring the noise a worker is exposed to at the workplace does not exceed the exposure standard for noise
– providing audiometric testing to a worker who is frequently required to use personal hearing protectors to protect the worker from hearing loss associated with noise that exceeds the exposure standard.
Designers and manufacturers of plant must ensure the plant is designed and manufactured so that its noise emission is as low as reasonably practicable. In addition, they must provide information about the noise emission values of the plant and any conditions necessary for minimising the risk of hearing loss and other harm.
Officers – Those in a position who can make, or participate in making, decisions that affect the whole, or a substantial part, of the business of the corporation, such as company directors, have a duty to exercise due diligence to ensure that the business or undertaking complies with the WHS Act and Regulation. They must take all reasonable steps to ensure that the business or undertaking has and uses appropriate resources and processes to eliminate or minimise the risk associated with noise in the workplace.
Workers – Any person who carries out work for a PCBU has a duty to take reasonable care for their own health and safety and that they do not adversely affect the health and safety of other persons. As a worker, you must comply with any reasonable instruction, policy or procedure relating to health and safety at the workplace. e.g. if you have been provided with hearing protectors by your PCBU, you must wear them in accordance the information, instruction and training provided on their use.
What is required to manage the risks associated with hearing loss?
According to the WHS Regulation, a duty holder must: identify reasonably foreseeable hazards that could pose a risk eliminate the risk so far as is reasonably practicable if not able to eliminate the risk, minimise the risk so far as is reasonably practicable by implementing control measures in accordance with the hierarchy of control maintain the implemented control measures so that they remain effective Review, and if necessary, revise, risk control measures so as to maintain so far as is reasonably practicable, a work environment that is without risks to health and safety.
The Code of Practice – Managing Noise and Preventing Hearing Loss at Work, provides guidance on how to manage the risks of hearing loss associated with noise by following a systematic process involving:
– Identifying sources of noise that may cause or contribute to hearing loss
– Specialist skills in identifying sources of hazardous noise may not be required, but you must undertake the process in consultation with your workers and their HSR/s. As a guide, if you need to raise your voice to communicate with someone about one metre away, the noise is likely to be hazardous to hearing.
Inspecting the workplace by regularly walking around and talking to workers and observing how things are done can help you identify noise hazards
Review available information regarding noise levels from manufacturers or suppliers of plant and equipment that is used at the workplace. Seek advice and information from regulators, industry associations, unions, technical specialist and safety consultants regarding hazards relevant to your industry. Review your workers compensation claims – have there been any previous claims made for hearing loss. Has there been any history of hearing loss or tinnitus found during audiometric testing
What should you do if you identify activities that may pose a risk?
If after consultation with workers and reviews you have identified any noisy activities that may expose your workers or others at your workplace to hazardous noise then, unless you can reduce the exposures to below the standard immediately you should assess the risks by carrying out a noise assessment. Noise assessments will help you:
– Identify which workers are at risk of hearing loss Determine what noise sources and processes are causing that risk
– Identify if and what kind of noise control measures could be implemented
Check the effectiveness of existing control measures.
Controlling the risks
The WHS Regulations require duty holders to work through a hierarchy of control to choose the control measure that most effectively eliminates or minimises the risk in the circumstances. The hierarchy ranks the ways of controlling the risk of hearing loss from noise from the highest level of protection and reliability to the lowest so that the most effective controls are considered first.
If it is not reasonably practicable to eliminate the source of noise, you must minimise the risk associated with hearing loss so far as is reasonably practicable. This includes ensuring that the noise does not exceed the exposure standard by choosing one or more of the following measures:
- substitute the hazard with plant or processes that are quieter
- modify plant and processes to reduce the noise using engineering controls
- Isolate the source of noise from people by using distance, barriers, enclosures and sound-absorbing surfaces.
If there is a remaining risk, it must be minimised so far as is reasonably practicable by implementing administrative controls, and if a risk still remains, then suitable personal protective equipment must be provided and used.
Effective risk control may involve a single control measure or a combination of two or more different controls.
When implementing a training program, the training should be provided to:
- those workers who may be exposed to hazardous noise or other agents that may contribute to hearing loss
- their managers and supervisors workplace health and safety committees and health and safety representatives
Those responsible for the purchase of plant, noise control equipment, personal hearing protectors and for the design, scheduling, organisation and layout of work.
The contents of the training program should include:
- the health and safety responsibilities of each party at the workplace
- how hearing can be affected by exposure to noise
- the detrimental effects hearing loss and tinnitus have on the quality of life, both at work and socially
Once you have consulted with your workers and have identified that your workplace may have noise related risks, please refer to the appendices in the Code of Practice – Managing Noise and Preventing Hearing Loss at Work – December 2011, as detailed below, as they will assist you in determining the level of risk and the appropriate control options available.
Typical Sound Levels
The following table lists some common noise sources and their typical sound levels which can be used to compare whether noise in the workplace sounds as loud as, or louder than the 85dB(A)
140db – Jet engine at 30m
130db – Rivet hammer (pain can be felt at this threshold)
120db – Rock drill
110db – Chain saw
100db – Sheet-metal workshop
90db – Lawn Mower
85db – Front end loader
80db – Kerbside heavy traffic
80db – Lathe
70db – Loud conversation
60db – Normal conversation
40db – Quiet radio music
30db – Whispering
0db – Hearing threshold
Legal Limits for Noise
A PCBU must ensure that appropriate risk control measures are taken when noise levels in the workplace:
- Exceed an eight hour noise level equivalent of 85 dB – Whether the exposure standard of 85 dB(A) averaged over eight hours is exceeded depends on the level of noise involved and how long the workers are exposed to it.
- Peak at more than 140 dB – 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.
Who can carry out testing to determine the level of noise in my workplace?
A simple visual and aural assessment may be required if the noise is from a single source
and is obviously loud. There are often simple changes you can make to significantly reduce
the noise, such as removing the noise source or enclosing it. Further information is available
for the NSW WorkCover Website where it states the following people can carry out testing:
- competent person
- industrial association, insurance company or risk assessor, or
- Acoustical consultant
A noise assessment may not always need measurement. e.g. If the identified activity is using a particular machine, and the manufacturer has provided information about the machine’s noise level when in operation, then a sufficient assessment can be made without measurement.
Where noisy equipment is used at various times for various periods, a visual and aural inspection may not be sufficient to determine levels of noise exposure.
The Code of Practice – Managing Noise and Preventing Hearing Loss at Work states a noise assessment should be done by a competent person in accordance with the procedures in AS/NZS 1269.1 Measurement and Assessment of Noise Emission and Exposure. The more complex the situation, the more knowledgeable and experienced the persons needs to be.
A competent person is one who has accurately calibrated noise measuring instruments and, through training and experience:
– Understands what is required by the WHS Regulations for noise
– Knows how to check the performance of the instruments
– Knows how to take the measurements properly, and
– Can interpret the results of the noise measurements.
Firms providing this service are listed in the Yellow Pages telephone directory under the headings ‘Acoustical Consultants’, ‘Noise Control Equipment’ and ‘Hearing Conservation Consultants and/or Services’.
It is a requirement of the WHS Regulations (58), that a PCBU must provide audiometric testing for a worker who is carrying out work for the business or undertaking if the worker is required to frequently use personal hearing protectors as a control measure for noise that exceeds the exposure standard – i.e. exceeds an eight hour noise level equivalent of 85 dB or peaks at more than 140 dB.
Before introducing an audiometric testing program, you must consult with your workers and their health and safety representatives. It is important that your workers understand that the aim of the testing is to evaluate the effectiveness of control measures to protect their hearing.
Audiometric testing and assessment of audiograms should be carried out by competent persons in accordance with the procedures in AS/NZS 1269.4:2005 – Occupational Noise Management – Auditory Assessment.
Using Personal Hearing Protectors – 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.
WHS Act 2011
WHS Regulation 2011
NSW WorkCover – NSW Occupational Disease and Wellbeing Strategy 2011-2015
AS/NZS 1269.1 Measurement and assessment of noise emission and exposure
AS/NZS 1269.4:2005 – Occupational Noise Management – Auditory assessment
Code of Practice – Managing Noise and Preventing Hearing Loss at Work – December 2011
Appendix A – Other Causes Of Hearing Loss In The Workplace
Appendix B – Noise Hazard Identification Checklist
Appendix C – Ready Reckoner
Appendix D – Contents Of A Noise Assessment Report
Appendix E – Engineering Control Measures