Investigation on the ergonomic aspects of the noise caused by chainsaw in bucking operation Case study: Kheyrud forest research station)

Forest workers are exposed to many noise sources such as chainsaw. Chainsaw these days is the only cutting trees instrument used in Caspian forests. The purpose of this study is to measure the noise of pressure levels of chainsaw and to determine the duration of worker exposures to that noise. The study area is located in Namkhane district, Kheyrud forest. The noise intensity of chainsaw and duration of cutting time in bucking phase were measured every 15 seconds, and then the average of noise intensity and cutting time for each trunk were calculated. The results showed that the workers usually work in exposure to the noise (107.9 122.7dB) higher than the standard level (85dB) that approximately shifts to painful threshold. The duration of bucking time was between 0.12 to 12.03 minutes and the noise intensity was 116 dB. According to the Iran standard and ACGIH, the standard bucking time is 24 seconds, while in this study it was 12.02 minutes. The duration of bucking time was more than standard level most of the time (more than %95 of time study). This study also showed that by increasing the trees trunk diameter, workers will be more exposed to the noise.