Noise-induced hearing loss

Noise is commonly described as unwanted sound. Most people are exposed to noise every day of their lives – it’s a common facet of modern life. Exposure to excessive noise may however have significant consequences, including causing permanent damage to hearing ability. Once you have damaged your hearing there is no going back – it is gone forever.

How can you, as an employee, determine if you are at risk of exposure to damaging noise and possibly developing noise-induced hearing loss (NIHL)? Ask yourself the following questions about your experience of noise at your workplace:

• Is the noise intrusive? – does it affect you for most of the day?
• Do you have to raise your voice to have a normal conversation with someone standing close by?
• Do you operate power tools or noisy machinery?
• Do you work in an industry which is generally recognised as being noisy? – e.g. manufacturing, mining, construction, engineering, fabrication, foundries, workshops etc?
• Are you exposed to any impulsive noise or impact noise – i.e. noise generated by hammering activities, pneumatic impact tools, presses, explosions, firearms, etc.
• At the end of your shift is your hearing slightly muffled or do you have ringing in your ears? Does this get better over weekends when you are not at work?

If you can answer yes to any of these questions, you may be exposed to excessive noise and at increased risk of developing NIHL.

NIHL normally develops gradually and progressively unless you are exposed to explosions or similarly loud impact noises. Unfortunately, by the time most people recognise or notice the symptoms of hearing loss, it is already too late. NIHL must therefore be actively prevented.

In terms of the South African Occupational Health and Safety Act: Noise-Induced Hearing Loss Regulations, if any workers are at risk of exposure to potentially excessive noise rating levels, an employer is required to have a noise survey performed by a Department of Labour Approved Inspection Authority (AIA). The noise survey will measure and assess noise rating levels to which workers are exposed and identify any noise zones on site – i.e. areas in which 8-hour time-weighted average noise rating levels exceed the Statutory limit of 85 dBA. Noise zones must be clearly identified and demarcated using floor markings and/or symbolic safety signage. All workers who are engaged within a noise zone must be issued with approved hearing protective devices (HPD) and must be subject to audiometric testing in accordance with Statutory requirements. The AIA will be able to make appropriate recommendations about the right type of HPD needed for particular noise zones as well as practicable ways and means by which noise exposures can be reduced.

As a worker, you must co-operate and assist your employer to do what is needed to protect your hearing. This is best achieved by ensuring that you:

• Make diligent and correct use of HPD if you work within a noise zone or make use of noisy tools/equipment
• Make proper use of any noise control mechanisms aimed at reducing noise within the workplace – e.g. machine enclosures, dampers, etc.
• Take proper care of your HPD and all other protective equipment issued to you
• Report any increase in noise within your area of responsibility so that it can be addressed promptly
• Report any problems with your HPD or any noise control devices straight away
• Report any hearing problems to your supervisor, manager or safety rep as soon as possible

Noise-induced hearing loss is a serious problem in many industries and it costs many millions of Rand each year to diagnose, treat and care for affected workers.

Remember, NIHL is permanent and cannot be reversed. Take all measures necessary to protect your hearing.