The effect of tree species on the occupational exposure in forest workers caused by hand-arm vibration using chainsaw

This research was conducted with the aim of measuring the hand-arm vibration of the chainsaw operator during the cutting and bucking operations of three tree species, including hornbeam, beech, and Persian ironwood, in the Patom section of Kheyrud Educational and Research Forest. In this research, three tree trunks of the mentioned species were measured simultaneously in three x, y and z directions of a chainsaw using a SVANTEK 106 vibration meter. The results showed that the average vibration equivalent to a chainsaw in all three axes in the Persian ironwood was higher than the other two species of hornbeam and beech. The amount of vibration of the whole chainsaw during the cutting of hornbeam, beech and Persian ironwood trees in the rear handle was significantly higher than the front handle. The results of the t-test showed that the total amount of vibration of the chainsaw during sawing of hornbeam, beech and Persian ironwood in the rear handle is significantly higher than the front handle. The results of Tukey's test showed that the average total chainsaw vibration in Persian ironwood and beech is significantly higher than hornbeam. The results showed that the vibration transmission coefficient in beech and Persian ironwood during cutting and bucking in the front and rear handles is significantly more than the measured amount of hornbeam. The results showed that the amount of daily exposure time in both two hours and three hours was significantly higher in Persian ironwood and beech species than hornbeam (both cutting and bucking stage). The results also showed that the predictive value of the duration of white hand disease in both two hours and three hours, in the Persian ironwood and beech species is significantly higher than hornbeam (both cutting and bucking stage).