Objective: To report audiological characteristics in a group of noise-exposed crew members on board ships.
Methods and materials: Clinical and audiological measurements including pure-tone thresholds, acoustic immittance results and tinnitus questionnaires were collected from both the ship crew members (study subjects) and their land based colleagues (controls).
Results: 1) Noise exposed crew members showed not only high frequency, but also low frequency hearing loss; 2) Hearing impairment increased with age, with 65.5% of crew members younger than 50 years showing normal hearing while only 14.9% of those older than 50 years had normal hearing; 3) hearing loss gradually increased with the extension of on board career time; and 4) Most study subjects reported high pitch tinnitus, significantly more than the control group although not significantly different among different age groups.
Conclusion: Noise induced hearing impairment from working on board ships shows specific frequency and age characteristics. Understanding these characteristics is important for advancing relevant studies and for effective prevention of noise-induced hearing loss in ship crew members.
Keywords: Age-related hearing loss; Hearing loss; Noise; Noise-induced hearing loss; Tinnitus.