Risk factors related to occupational noise-induced hearing loss among workers in an automobile manufacturing enterprise

Objective To understand the occurrence of hearing loss among occupationally noise-exposed workers in an automobile manufacturing enterprise, and to explore the risk factors.

Methods A total of 3 411 workers who were exposed to occupational noise with time longer than 1 year in this enterprise were studied with questionnaire and their working environment was surveyed.

Results Among 3 411 workers, 509 workers were found with hearing loss and the incidence of noise-induced hearing loss in this enterprise was 15.7%. There were significant difference of noise exposure intensity and time, the workers' marriage status and arrangement of work shift between two groups(P < 0.05). Multivariate logistic regression analysis showed that except for the workers' age, noise exposure level and noise exposure time(OR=1.09-1.54, P < 0.01), single shift or two shifts system was also an independent risk factor for hearing loss (OR=2.19, 2.43, P < 0.01 or 0.05) compared with three shifts system.

Conclusion The noise hazard at workplaces in automobile manufacturing enterprises could not be ignored. Enterprises should strengthen the control of workplace noise, conduct regular occupational health examinations for noise-exposed workers, and develop a scientific and healthy work schedule.