Hearing loss of noise-exposed workers in a printery during 2010-2012

Objective To investigate the long-term effect of occupational noise exposure on hearing of workers in a printer. Methods The results of the pure tone audiometry test for three consecutive years were analyzed. The dynamic change of hearing was evaluated and potential affecting factors were probed. Results The hearing loss at both 4.0 kHz and 6.0 kHz frequency was significantly increased with the prolongation of noise exposure time (F=1.333,1.045,P<0.05). The workers with 10 years of employed time or more had a higher rate of hearing loss (46.51%)compared with the workers with employed time less than 10 years(14.48%). Male,noise intensity above 85 dB(A),10 years of exposure time or more,and 50 years of age or more were independent risk factors for hearing damage(OR=2.721,2.376,2.044,2.816). Conclusion There was a dose-response relationship between the noise exposure and hearing loss and the effective control measures against noise in this printer should be taken promptly.