Noise

The noise level in a workplace is considered harmful and a major cause of hearing loss if it exceeds the exposure standard. The exposure standard for noise is defined in the Work Health and Safety Regulation 2011 as 85 decibels (A-weighted) 'averaged' over an eight-hour period, and a peak level of 140 decibels (C-weighted).The standard relates to noise measured at the worker's ear.

The Work Health and Safety (Managing Noise and Preventing Hearing Loss at Work) Code of Practice 2011 sets out a range of measures to minimise hearing loss at work.

Identify the risks

Due to the use of noisy equipment and machinery high noise levels are almost always present on construction sites.

The following table provides indicative daily noise level exposure.

Workers' expertise can make a significant contribution when identifying, assessing and making decisions about risks associated with exposure to excessive noise. Therefore workers (including contractors) should be regularly consulted.  It is likely that the exposure standard is being exceeded if workers:

• find it difficult to hear someone speaking to them from one metre away
• notice a temporary hearing loss or ringing in the ears after leaving work
• need to use hearing protectors.

Noise exposure levels can also be identified by taking spot noise measurements. The more complex the situation, the more knowledgeable and experienced the person doing the assessment needs to be. In some cases, such as when there are multiple sources of noise, the assessment is best conducted by a specialist.

What is the impact of noise?

Exposure to noise can damage the nerve receptors in the inner ear. Once the damage is done it cannot be reversed.

Immediate damage can result from exposure to impulsive noise such as the noise produced by a powered nail gun. Most noise induced hearing loss occurs gradually over many years of continual exposure to noise.

Exposure to low noise levels may interfere with activities or concentration. Continual exposure may cause stress and other adverse health effects.

Exposure to high levels of noise may initially cause dull hearing and ringing in the ears. Regular high level noise exposure will lead to loss of hearing and other adverse health effects.

Significant hearing loss can increase absenteeism, worker turnover and lower work performance and career prospects. Hearing loss also contributes to communication problems and workplace injuries and accidents as workers are unable to hear directions, warning sounds and alarms. Hearing loss may also contribute to social isolation and reduced quality of life as relationships with loved ones, family, friends and work colleagues may suffer.

Exposure to noise can:

• annoy and interfere with speech
• interfere with concentration and thought processes
• disturb sleep
• cause stress, fatigue and aggression
• cause irritability and headaches
• cause tinnitus (ringing in the ears)
• cause slow, painless and permanent hearing loss
• reduce immune response
• lead to heart disease
• raise blood pressure
• accelerate heart rate
• lead to gastric ulcers.

Reducing the risk

The Work Health and Safety Regulation 2011 requires a person conducting a business or undertaking to manage the risks to health and safety relating to the loss of hearing from exposure to noise.

While excessive noise remains a significant issue in many workplaces solutions for eliminating or limiting noise exposure can be readily implemented. In many instances, a combination of approaches will result in the best solution. Some strategies in relation to managing exposure to noise include:

• eliminating the source of the noise by removing a noisy piece of equipment from the workplace
• using quieter equipment such as a quieter compressor
• using quieter processes such as welding instead of riveting and avoiding metal-on-metal impacts
• using engineering controls such as sound absorptive materials, isolating vibrating machinery and erecting enclosures, barriers and screens
positioning noise sources away from workers
• minimising the number of workers working in noisy areas
• undertaking noisy work outside of normal working hours
• job rotation
• the provision and use of personal hearing protectors
• audiometric testing
• training about the effects of exposure to noise, control measures and selection, fit and maintenance of hearing protectors.