ABSTRACT
Objective To investigate the incidence and risk factors of hearing loss among the workers exposed to non -stationary noise.Methods A cross -sectional study was conducted among the participants.571 male workers without any history of ear disorder were enrolled in this study.They had been exposed to non -stationary noise for one year or more. The history of noise exposure,smoking and drinking behavior were interviewed by using a questionnaire.The noise exposure in the workplace was measured at eight -hour equivalent noise level (LEX.8h )and the thresholds of hearing at 500,1 000,2 000,3 000,4 000 and 6 000 Hz were detected.Results The prevalence of high -frequency hearing loss of two ears was 52.54%,while the prevalence of hearing loss of one ear was 71.98%.There were significant differences of prevalence among different groups of workers in LEX.8h ,duration of noise exposure and the cumulative noise exposure (CNE)(P <0.01).There was a dose response relationship between noise exposure and the risk of hearing loss (P <0.01).Conclusion Non -stationary noise exposure may contribute to hearing loss of workers.There is a good dose -effect relationship between the hearing loss and non -stationary noise.