The Study of High Frequence Hearing Loss in Pilots

ABSTRACT

BACKGROUND: Hearing loss is associated with environmental noises. Not only the strength of the noise but also the exposure time of that seems important. We investigated to find the factors associated with hearing loss in pilots. METHOD: For the anlysis of hearing loss in pilots in the air force, we performed an audiometiric test on 563 pilots from 2000 to 2001 and analysed the results. REUSLT: The type of aircraft or regiment is not associated with hearing loss. The age, tenure and total flight time are the factors associated with hearing loss, especially in the high frequency zone. The flight time in the recent six months is shown not to be associated with hearing loss which means an exposure to noise in a longer term is important. In this study, the hearing threshold increased at 6,000 Hz regardless of age. CONCLUSION: The reason may be due to the noise environment of pilots. Therefore an additional study about pilots' normal limits of hearing threshold at 6,000 Hz and clinical meanings of that is necessary.