Evaluation of Noise Pollution Levels in Manufacturing Sectors in Thika District-Kenya

Abstract

xvi ABSTRACT Noise is considered as any unwanted sound that may adversely affect the health and wellbeing of individuals or populations exposed. This study assessed the magnitude of occupational noise exposures to workers in different manufacturing sectors in Thika District-Kenya. Systematic random sampling was used to select eight manufacturing companies (one per sector) from Directorate of Occupational Safety and Health Services and Kenya Association of Manufacturers registered workplaces in Thika District. Thika district was selected because of its high concentration of manufacturing companies. Data was collected through; environmental noise survey, questionnaire survey, observation and secondary data for comparison. A sample size of 400 (out of 2400 employee) participants from the eight selected manufacturing industries were randomly recruited in this study as per the table of maximum return of sample. In this study the males population was high (82%) as compared to females (18%), hence gender had a significant association between the companies sampled. This study also found that the generator department recorded the highest values of between 88.7–96.4 dBs (χ2 = 2.40; p < 0.05, df = 1.00) while the office department recorded the lowest values of between 38.1–50.1 dBs (p < 0.05) in all the selected companies. The production department had the highest exposure magnitude in relation to employees. The companies’ noise exposure levels had significant association in terms of office departments (p = 0.04). The study concludes that magnitude of noise exposure to the workers in generator and production units of manufacturing industries in Thika District is high and recommends strict enforcement of noise control regulations supported by necessary trainings, policies and personal protective equipments.