1999 Volume 1999 Issue Supplement101 Pages 131-134
Acting on a government guideline enacted in 1992, hearing examinations were performed on 492 employees working at a noise exposed manufactoring plant.
Audiometry revealed 221 cases of noise-induced hearing losses (44.9%), and 54 abnormal findings (11%). In the latter cases,29 patients with neural and 9 with conductive hearing loss were identified on additional otological tests. In the noise-induced hearing loss group,95% of the subjects were grade I. The longer the workers were exposed to noise, the greater was the hearing loss. One hundred and fifty of the 221 cases of noise-induced hearing loss were aware of their hearing disturbance, tinnitus or both. In spite of these problems, the proportion of sound-proofing users increased only gradually. Howerer, the proportion of sound-profing users was not high (57.9%), and thus this could be improved. The noise levels of this factory were reduced to below Leq 90 dB (A), and the work environment were improved.
We conclude that education on hearing health and the greater usage of sound-proofing is important in preventing hearing impairments.
