It is not an overstatement to say that one of the most critical issues facing every business owner in our industry is the exposure of their employees to hazardous noise at the workplace. Too much noise at work can lead to temporary or permanent hearing loss or a condition of tinnitus/ringing in the ears. Although clearly noise is a common occurrence in any frame or truss plant or workshop, this does not mean that it can be accepted as normal and no attention given to noise reduction strategies.
The hearing loss is a result of the hair cells in the inner ear being permanently damaged – and once they are destroyed, they never grow back.
Damage to hearing usually happens over a number of years and is known as noise induced hearing loss (NIHL). It is a permanent condition that can have a negative impact on a worker’s life as well as significant financial consequences for any business owner in our industry.
Hearing Loss: A Snapshot
- From 2001–02 to 2014–15 there were 65,300 accepted claims for deafness in Australia. This was an average of 4,700 per year.
- Over one-third (35%) of these claims were made by employees in the manufacturing industry while 18% came from construction.
- The primary mechanism that led to deafness was long-term exposure to sounds arising from working inside.
- In 2007–08 $41 million in workers’ compensation payments were made with an estimated total economic cost of around $240 million.
Too Much Noise: a definition
In the model WHS Regulations the exposure standard for noise involves two measures:
LAeq,8h of 85 dB(A) means that over an eight-hour shift a worker can’t be exposed to more than 85 decibels. Whether this is exceeded depends on the level of noise involved and how long a worker is exposed to it.
LCpeak of 140 dB(C) means a worker can’t be exposed to a noise level above 140 decibels. Peak noise levels greater than this 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.
- The risks from workplace noise must be eliminated or minimised so far as is reasonably practicable.
Business Responsibilities
Employers have specific obligations under the WHS Regulation.
You must:
make sure the noise a worker is exposed to at the workplace doesn’t exceed the exposure standard for noise
- provide audiometric testing to workers who are frequently required to use personal hearing protection. The obligation to provide audiometric testing (Cl 58) came into force on 1 January 2017.
Designers and manufacturers of plant must make sure the plant is designed and manufactured so that it emits the least amount of noise (as reasonably possible). They must also provide information about the noise emission values of the plant, the operating conditions of the plant when noise emission is to be measured, and the methods the designer has used to measure the noise emission of the plant.
Identifying Hazards
The potential for noise to be hazardous is not always obvious. The effects of long-term exposure are cumulative, and a worker may carry out a number of noisy work activities that over time expose them to hazardous noise.
As a business owner you must identify hazardous noises in consultation with your workers and their health and safety representatives.
- A quick test you can do to assess the noise in your workplace is the ‘one metre rule’. If you need to raise your voice to talk to someone about one metre away, you can assume the sound level is likely to be hazardous to hearing. You could also inspect the workplace by regularly walking around, talking to workers and observing how things are done. Find out where noise is coming from and which tasks or processes produce it. Take immediate action to control noise where possible, for example fix loose panels that are vibrating and rattling during machine operation.
You should also review available information regarding noise levels from manufacturers or suppliers of plant and equipment used at the workplace.
Also check whether any workers’ compensation claims have been made for hearing loss and if any hearing loss or tinnitus has been found during repeat audiometric testing. If a worker’s hearing has been affected and this has been attributed to a particular task, then a hazard may exist that could affect other workers.
Managing Risks
If you have identified any noisy activities that may expose workers or others to hazardous noise, unless you can reduce the exposures to below the standard straight away, you should assess the risks by carrying out a noise assessment.
A noise assessment 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 measurescould be implemented
- check the effectiveness of existing control measures.
A noise assessment may not always need measurement. For example, if only one activity at the workplace—using a single machine—involves noise above 85 decibels and the manufacturer has provided information about the machine’s noise levels when it is operated in particular ways, then a sufficient assessment can be made without measurement.
More complex situations may need measurement to determine a worker’s exposure to noise, such as workplaces with variable noise levels over a shift and jobs where workers move in and out of noisy areas. In these cases, if you contact TTIA regarding a noise assessment.
Steps to Control Noise in a Workplace
The model WHS Regulations require duty holders to work through a hierarchy of control to choose the measure that eliminates or most effectively minimises the risk in the circumstances.
- The most effective control measureis to eliminate the source of noise completely. Can you plug electrical equipment into mains supply instead of using a noisy generator? Can you replace hand-held power tools with an automated process that doesn’t produce noise?
- If you can’t eliminate the noise look at reducing it. Can you substitute noisy pieces of plant with less noisy ones? Can you move the equipment further away with the use of extension cords, additional welding leads, or longer air hoses?
Remember that actions to eliminate or minimise noise may introduce new hazards, and risks associated with those hazards need to be managed effectively.
Other ways to minimise noise include:
- Engineering controls. These are a common control measure. You might modify equipment to reduce noise at the source, or place barriers of plywood around the source. You might also place barriers along the transmission path to reduce noise levels or place them around the worker to prevent noise exposure.
- Administrative controls. These include operating noisy machines during shifts where fewer people are exposed, limiting the amount of time a person spends near a noise source, moving workers away from the noise source to reduce their exposure, or providing quiet areas where workers can gain relief from hazardous noise sources.
- PPE. Personal hearing protectors such as ear-muffs or ear-plugs should be used:
- when the risksarising from exposure to noise can’t be eliminated or minimised by other more effective control measures
- as an interim measure until other control measuresare implemented
- where extra protection is needed above what has been achieved using other noise control measures.
The risk of occupational noise-induced hearing loss is increased by relying too much on, and improperly using, personal hearing protectors such as ear muffs and plugs.
Easy ways to keep noise levels low
- Buy the quietest plant and machinery for the job and always ask the manufacturer/supplier for information about noise levels.
- Change the way you do the job, for example glue don’t hammer, weld don’t rivet, lower don’t drop.
- Reduce noise levels at the source, for example fit silencers to exhausts, turn down the volume, change fan speeds.
- Isolate the source of the noise, for example use barriers, remote controls or sound-proof covers.
- Reduce exposure levels, for example restrict access to noisy areas, provide quiet areas for rest breaks, or limit time spent in noisy areas by rotating tasks.
- Proper maintenance of equipment and tools can result in lower noise levels.
Audiometric Testing
Under the model WHS Regulations, a business owner must provide audiometric testing for a worker who is carrying out work if they are required to frequently use personal hearing protectors as a control measure for noise that exceeds the exposure standard.
- Audiometric testing must be provided within three months of a worker starting work that exposes them to a risk of work-related noise-induced hearing loss.
Starting the audiometric testing before people are exposed to hazardous noise (such as new starters or those changing jobs) provides a baseline as a reference for future audiometric test results.
Regular follow-up tests must be carried out at least every two years. These should be carried out well into the work shift so that any temporary hearing loss can be identified. If you need any assistance on this testing process, please contact TTIA on (02) 9264 0011.
TTIA has a Workplace Health & Safety Unit which can assist you on noise issues raised in this article as well as other Workplace Health & Safety issues.