A survey on hearing of workers exposed to noisy environment in a cotton spinning mill

Abstract

Objective To explore the effect of high intensity noise on the hearing in the workers in a cotton spinning mill. Methods A hygienic survey on the workplaces in a cotton mill was conducted. The results of hearing examination on 195 workers exposed to the noisy environment were compared with those from 108 controls. Results A total of 110 noisy spots were detected, whose intensity ranged from 80.1 to 96.0 dB, with an average of (85.3 ± 2.6) dB. 42 detected spots (38.2%) exceeded the national hygienic standards. The incidence of hearing loss was significantly higher in the workers exposed to the noisy environment than in the controls (26.2% vs. 5.6%, P<0.01); and the degree of hearing loss increased with the length of the exposure time. Conclusions The workers exposed to such a noisy environment in the cotton spinning mill have a marked hearing loss. Key words: Cotton spinning mill; Noise; Hearing