Noise Induced Hearing Loss (Industrial Deafness)
What is it?
Noise Induced Hearing Loss (NIHL) is damage caused to the hair cells inside the
ear caused by exposure to constant levels of noise. The damage is not visible, and
is typically gradual in onset.
During the development of NIHL, there will at first be a loss mainly of outer hair
cells until the hearing loss becomes more severe and there starts to be significant
loss of inner hair cells.
The initial loss of hair cells does not cause any reduction of hearing sensitivity
and it can often be quite some time before the signs of any hearing loss become
noticeable. By that time, the damage is permanent and irreversible.
With further exposure to noise and further damage to the population of hair cells,
hearing sensitivity becomes affected. The higher frequencies of a person’s hearing
are typically affected which can mean that someone with NIHL has trouble picking
up some consonant sounds such as S’s, T’s, and F’s which affects clarity of speech
especially in background noise, rather than just a straight forward loss of volume.
How can you tell if someone has Noise Induced Hearing Loss?
The basic measurement tool is known as an audiogram which charts hearing thresholds
across the frequencies of hearing used for speech. It is best performed in a sound
proofed booth, and in a relaxed environment, although it is acceptable for the test
to be taken in another place provided that noise measurements have been taken which
confirm that the background noise is less than 30 decibels.
The test usually takes 20 minutes and involves wearing a set of headphones and pressing
a button when random sound patterns can and can’t be heard. It is often repeated
to ensure accuracy. A ‘typical’ audiogram for someone with NIHL is shown on the
next page.
It shows that the higher frequencies (khz +) are more affected, in both ears than
the lower frequencies.
The audiogram is a useful tool for diagnosis, but provides only part of the picture.
Science is only able to predict what component of the hearing loss is caused by
age, which leaves the extra loss explained by either a history of sustained noise
exposure or some other medical factor.
How does a claim work?
The starting point is to complete the online questionnaire
by clicking on this link.
Once you have submitted your enquiry we will tell you what your chances of making
a successful claim will be and we will contact you with details of an appropriate
solicitor, who will get in touch over the next couple of days.