Environmental Noise and the Association with Occupational Stress among Palm Oil Mill Workers

ABSTRACT: In palm oil mills the environmental sound level, resulting from operating machineries, is usually exceeding the action level of noise (85dB(A)). Whereas the excessive noise can develop chronic job stress, thus this study aims to determine the relationship between personal noise exposure and occupational stress among palm oil mill workers. A cross sectional study was done among 173 workers at five selected mills namely in Perak, Selangor and Negeri Sembilan. Environmental noise and personal noise exposure measured using Sound Level Meter (Model: Lutron SL-4112) and Dosimeter (Model: wireless110A) respectively. Alpha-amylase activity was used to determine the non-auditory effects of noise through determining the stress level. Results showed that, 100 % of the workers among exposed group (PNE≥85 dB (A)) experiencing stress condition while 43 % of non-exposed group (PNE<85dB (A)) experiencing stress condition. Statistically alpha amylase activity in stimulated condition among exposed group was significantly higher than non-exposed group (t-value=-3.983, p-value=0.000). As the conclusion, there is a significant relationship between alpha amylase activity and personal noise exposure among palm oil mill workers. (rs=0.725, p-value=0.000