Prevalence and correlates of hearing loss in a cement factory.

Objective. To assess the impact of occupational exposure to noise, as well as its relationship with other factors that can induce hearing loss. Material and methods. In January and February 1997, we conducted sonometry and dosimetry tests in a cement factory, as well as audiometric test in cement workers, to identify sources of noise and evaluate the effect to noise exposure and other factors, of the prevalence of occupational hearing loss. Statistical analysis was conducted using measures of central tendency, bivariate analysis and polynominal regression models. Results. High noise levels were found in the crushing, crude milling, and cement milling sites. The highest individual dose corresponded to the packer job post. Fifty-five per cent of the study population presented some degree of hearing loss due to noise exposure. The cement processing area with the highest percentage of damaged workers was calcination. Conclusions. Our results show that noise is a serious risk factor in particular sites of cement factories, and also that an elevated number of hearing loss cases are due to occupational noise exposure in this industry; Our findings underscore the need for designing and implementing hearing protection programs, to assure the health and safety of cement workers.