Hearing Acuity of Air Force Flight-Line Personnel: a Preliminary Report

Abstract

Pure-tone audiometric tests and job-, noise-, and medical-history questionnaires were administered to 599 Bergstrom Air Force Base flight-line personnel. Hearing loss at 4000 cps, total hours of exposure to high-level on-the-job noise, and age were analyzed to determine the inter-relationships between these three variables. At 4000 cps (worse ear) the observed mean hearing losses in eight Air Force Specialty groups ranged from 14.8 db to 20.6 db re audiometer zero. No statistically significant differences were found between group hearing-loss means when adjustment was made for differences in age and noise exposure. The interrelationships between hearing loss, age, and noise exposure were similar from one Air Force Specialty group to another. Hearing loss at 4000 cps and age were positively correlated. Age and noise exposure were positively correlated with hearing loss and noise exposure. The partial correlation coefficient between hearing loss and age differed significantly from zero. However, the partial correlation coefficient between hearing loss at 4000 cps and noise exposure was not statistically significant. These results are evidence that an extremely complex relationship exists between noise-induced hearing loss and age plus total exposure to high-level intermittent continuous noise. [This study was supported by funds provided under contract AF 41(657)-35 with the School of Aviation Medicine, U. S. Air Force, Randolph Air Force Base, Texas.]