Noise level analysis of a bulldozer used in constructing a forest road in Mediterranean region of Turkey

Heavy machinery utilized in forest operations, as one of the working environments with intensive noise disturbance, result detrimental effects on the workers’ health. Particularly, high level noise generated from the road construction machines causes physiologic and psychological health problems on the operators. Among these problems, one of the most important occupational problems is hearing impairment or permanent hearing loss. In this study, the average and peak noise levels generated by a CAT D7G model bulldozer during two working stages (that is, unloaded running stage and road construction stage) of a road construction activity were measured from the operator cabin. The results indicated that the average noise levels for unloaded running stage and road construction stage were 73.87 and 84.11 dBA, respectively. The peak noise levels were measured as 95.90 and 113.40 dBA for unloaded running stage and road construction stage, respectively. Thus, it was found that the mean values of the average noise levels in both working stages were less than the warning limit of 85 dBA. The results also indicated that all of the peak noise levels were over the hazard limit of 90 dBA for both stages.