Risk assessment of influence factors on occupational hearing loss in noise - exposed workers in typical metal industry

Worker exposure conditions such as noise level، exposure duration، use of hearing protection devices and health behaviors are commonly related to noise induced hearing loss. The objective of this study was risk assessment of influence factors on occupational hearing loss in noise exposed workers in typical noisy process. Information about occupational exposure of seventy workers employed in a noisy press workshop was gathered using the standard questionnaire. Audiometery test was performed using the screening audiometer (Model-Mevox). Afterward، the collected data was analyzed by using the Cox model in SPSS software. Based on results of the developed model، the job type and using status of HPD were most important features to induce hearing loss among workers. The risk of hearing loss among workers with the intermittent use of hearing protection was 3. 1 times more than workers used their devices continuously. Relative risk of hearing loss among smoker workers compared with non-smoker was 1. 1. The developed model could determine the effects of workers’ exposure conditions on risk of occupational hearing loss. This systematic approach can be considered as a helpful tool for determination the effectiveness of hearing conservation program and provide useful information for the managers and professionals in order to revise the existing health programs.