Noise Pollution Assessment and Control for Construction Diesel Generators in Hamadan, Iran

Since using city power for welding process is not allowed, diesel generators are used as a power supply in construction industries. They could be introduced as a main source of noise pollution. The purposes of this study were to assess and control noise pollution produced by construction diesel generators in Hamadan, Iran. In this descriptive, cross-sectional study, sound pressure level (SPL) was measured in 4 points at a distance of 1 meter from a diesel generator. Frequency analysis was also conducted for stations with SPLs higher than the standard limit. The noise disturbance questionnaire was then used to investigate noise disturbance among neighbors. Appropriate mufflers were designed to reduce SPL based on the objectives of the study. Finally, data was analyzed by SPSS13. Our results showed that the mean values of SPL around the generators and on the nearby streets were 97.0 ± 2.2 and 74.0 ± 7.4 dB(A), respectively. These values both exceeded the recommended levels. Overall, 60.7% of the neighbors were disturbed by the noise from construction activities. Using the designed muffler in the Benz model, SPL reduction at 63 Hz was 24.4 dB and total reduction was 11 dB. The corresponding values were 21.2 and 9.5 dB in the Romania model. Exhaust system was a main source of noise in diesel generators. Therefore, appropriate mufflers would reduce noise pollution.