Abstract
Background: Noise-induced hearing loss (NIHL) is one of the most common occupational diseases affecting foundry workers in South Africa. Medical surveillance is an important consideration in this industry and an integral part of hearing conservation efforts by occupational health practitioners.
Objectives: The purpose of this study was to describe the prevalence of and predisposing factors for hearing impairment among foundry workers. Furthermore, the study was conducted to quantify the problem and assess the risk profiles of these workers, and recommend strategies for improved hearing conservation programmes (HCP) in the occupational health setting.
Methods: This was an analysis of secondary data from the hygiene surveys and occupational health records of 194 foundry workers employed during 2021. Data were analysed using descriptive statistics. Secondary data was collected from occupational health medical records, and a total of 194 data extraction forms were completed.
The data was analysed by running frequencies and descriptive statistics. Frequency distribution tables were computed, and means, medians, and standard deviations were used to compute the central tendency and dispersion of the data. Pearson's chi-square test was used to compare the observed results with expected results and to determine the relationship between the variables. A p-value of < 0.05 was considered significant.
Results: The records indicated that the workers in some departments were exposed to dangerously high noise levels, exceeding 85 dBA. The audiometry records contained appropriate and relevant data, including annual hearing screening percentage loss of hearing (PLH) shifts; there was evidence of significant threshold shifts for ten participants; and the point prevalence of NIHL among this study population of workers was 2.58%. Significant associations were found between PLH and age, race, duration of exposure, and the work department.
Conclusion: The hazardous noise levels recorded call for improved occupational health and safety control measures to protect workers from this incurable occupational disease.