The most common work-related disorder-a-noise-induced hearing loss, significantly affects 60% of factory workers in the manufacturing sector. The longer they work in this type of setting, the higher the risk of developing hearing problems.

According to the World Health Organization, the prolonged exposure to noise of 75 dB SPL for 8 consecutive hours or more can lead to a hearing loss. As well, being exposed to a louder noise but for a shorter period of time can also be damaging. In Quebec, more than 400 000 workers are exposed to levels of noise higher than 85 dBA/8 hrs. Think about what happens to you after a rock concert, when you talk very loud and need lots of repetition to hear. This is what it's like for a factory worder leaving his shift, day after day.

The loss of the hearing abilities is a slow and incidious process, it does not appear all of a sudden. The first symptom of this type of loss, is when a worker does not hear as well as usual having left the factory. This is caused by auditory fatigue (a temporary hearing loss), which can, if prolonged, become permanent. This phenomenon is caused by the progressive destruction of the auditory cells which have been subjected to high intensity noise. A sensorneural noise induced hearing loss affecting primarily high frequency sounds, is the consequence of this inner ear damage.

Real problems related to a noise-induced hearing loss will be felt outside of the working environment, eg, at home, shopping, at the bank, visiting friends, particularly when there is a significant background noise. It is the auditory sensitivity of the inner ear to different pitches whick is particularly affected. We often hear people say: "I hear, but I don't understand because I only hear the noise". Conflicts avise: the TV volume is too high; a spouse repeating all of the time; the family has the impression that the individual hears only what he wants; social invitations are refused; the individual prefers not to participate in family gatherings where is difficulties in hearing will be obvious - difficulties he may not be able to comfront.

Unfortunately, there is no cure for noise induced hearing loss, as it is the direct result of damage to one part of the inner ear. However, by consulting an audiologist, an individual with this type of handicap can find ways to reduce the problem that his hearing loss presents.