Agricultural machine operators are exposed to a number of occupational health and safety risks. Noise is considered as one of the most common occupational health hazards in farming activities. Aim of this study is to evaluate acoustical comfort and the noise levels exposed on the operators of the garden tractor. For this purpose, some factors were evaluated which affect the noise generated by a Goldoni garden tractor. Research factors were including engine speed, gear ratios and type of operation. During measurement and recording the sound signals of the garden tractor, the variables of engine speeds and gear ratios were varied to cover the most normal range of the garden tractor operation in tillage condition and transportation condition on the rural road. Accordingly, factorial experiments were performed in completely randomized design with three replicates. According to variance analysis with LAeq, PA and UBA, operation type, gear ratio and engine speed were found significant (P< 0.01). The results show that LAeq, PA and UBA for rural road are higher than tillage condition. Also, results indicated that the highest mean of LAeq, PA and UBA were 77.76dBA, 9.83 and 21.16, respectively and occurred in the case of rural road and 2100 r/min engine speed. The results of this study indicate that PA and UBA correlated strongly with LAeq analysis (R2=0.97).Therefore, the LAeq, obtained in this research, will be a good indicator of the PA and UBA.
