Hearing loss in relation to occupational noise levels among workers in a polyester fiber factory in Thailand

Abstract

Background: Excessive occupational noise is a problem in all regions around the world, and is associated with many work activities, including manufacturing. In Thailand, synthetic fiber production is one business which has high noise level in the workplace. So this study was a cross-sectional study conducted in a Polyester Fiber factory in Pathumthani province during May-June 2015. The purposes of this study were to find the prevalence of hearing loss and risk factors associated with hearing loss in 119 polyester fiber workers. The study areas were the cutting, spinning, and drawing processes which average 8 hours of noise exposure per day. In some areas noise level was more than 85 dB(A ).

Methods: Associations between dependent and independent variables were assessed with bivariate analysis and multiple logistic regression models. 

Results: The prevalence of hearing loss was 7.6%. There were 3 main analytical findings, as follows: 1. There was no significant association of any hearing loss with either of the measured noise levels (p > 0.05); 2. In all analyses, risk of hearing loss was significantly higher in subjects who did not always use ear plugs than in those who always used them; 3. Independent variables were more strongly associated with hearing loss in the right ear than with hearing loss in the left ear or hearing loss in either ear.

Conclusion: Although prevalence of hearing loss in this study was low, to reduce the burden of hearing loss in the future, hearing conservation programs, and safety and health education for industrial workers, would be desirable.