ABC of Work Related Disorders: OCCUPATIONAL HEARING LOSS AND VIBRATION INDUCED DISORDERS

Hearing loss In 1908 the annual report of the Chief Inspector of Factories stated: “men employed in certain trades are liable to have their sense of hearing seriously impaired, if not entirely destroyed in the course of time, as a result of long continued exposure to loud noise.” It is only in recent decades that this situation has begun to change.

This irreversible sensorineural deafness is caused by damage to the hair cells of the organ of Corti in the cochlea. It can be the cause of accidents due to failure to hear warning signals. It reduces the quality of life and, especially in elderly people, produces social isolation. If tinnitus is prominent psychiatric symptoms can occur.

Clinical presentation Noise induced hearing loss develops insidiously. A gradual loss of clarity in perceived speech occurs, which is often attributed to inattention or to others not speaking clearly because when the sufferer looks at speakers he or she can understand them. Difficulty in understanding others in a crowd is, in the same way, presumed to be due to competition with background noise (perceptual rivalry). Eventually, the sufferer realises that others do not have this problem. This realisation may come suddenly, such as when a telephone with an electronic bleep is bought to replace one with a bell.

A high pitched tinnitus, initially intermittent, becomes …