Evaluation of noise levels in manufacturing sectors in Thika district, Kenya
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 8 manufacturing companies (one per sector) from the Directorate of Occupational safety and Health Services (DOSHS) and Kenya Association of Manufacturers (KAM) 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 participants from the eight selected manufacturing industries was recruited in this study as per the table of maximum return of sample. The results showed that the males population (χ2 = 14.7; p < 0.05, df = 7) 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 value of dB(A) (χ2 = 2.40; p < 0.05, df = 1.00) while the office department recorded the lowest values (p<0.05) in all the 8 selected companies. The production department had the highest exposure magnitude in relation to employees (p=0.041). The companies’ noise exposure levels had significant association in terms of departments. The magnitude of noise exposure to the workers in manufacturing industries in Thika District is high (p<0.05) and recommends strict enforcement of noise control regulations supported by necessary trainings, policies and personal protective equipments. The data obtained can be used by National Environment Management Authority (NEMA) and DOSHS to develop monitoring and evaluation mechanisms for enforcement and compliance.
Key words: Noise, exposure, compliance, manufacturing, Thika, pollution