Changes in the hearing threshold of workers in a steel industry: 5-year follow-up
Introduction: noise is one of the most important harmful factors in the workplace. The physiological effects of noise on humans are gradual in the long run. Despite industrial advances, exposure to excessive noise is one of the health problems of workers in the world's steel industry. This study aimed to investigate the effect of noise on hearing loss in steel industry workers.
Materials and Methods: This descriptive cross-sectional study was designed and conducted. The study population was 121 workers in a steel rolling industry whose 5-year audiometry was studied from 1391 to 1395. An audiometer performed the audiometric test of these workers in 5 years. Their audiometric results were extracted from their medical records and examined under ethical principles. Data were analyzed using SPSS software version 21, and T-Test and Wilcoxon Signed Ranks Test was used for statistical analysis.
Results: The mean age of participants was 38.88 ± 4.92 years and the mean work experience was 10.94 ± 3.57 years. In this study, a gradual increase in the average hearing threshold at different frequencies in both ears was seen from 2012 to 2016.
Conclusion: noise as a detrimental factor in the steel industry causes a gradual increase in exposed workers' hearing threshold.