Hand-Transmitted Vibration Exposure to Tractor Operator during Tillage Operation

Abstract

An investigation was conducted to quantify hand-transmitted vibration exposure to the tractor driver. Three experienced tractor operators were chosen to measure the exposure during tilling operation. Three primary tillage implements namely mould board plough, disc plough and rotavator were selected for the experiments, which were operated at three levels of forward speed, i.e., 0.98, 1.37 and 1.54 m/s. Measurements were also done during idle condition. ISO 5349 (2001) guidelines were used for measurement and analysis of hand-transmitted vibration. Latency period for occurrence of vibration white finger was also calculated. The results indicate that root mean square (rms) vibration acceleration is negligible up to 25 Hz. The peak value of vibration acceleration was observed from 500 to 630 Hz. Vibration total values (rms) were relatively more during operation of rotavator and increase in speed of operation increased vibration acceleration. The effect of speed of operation on vibration acceleration was more during operation of rotavator. Analysis of variance indicated that vibration acceleration (rms) was significantly affected during operation of tillage implements (p<0.01) and speed of operation (p<0.05).Considering 8 h per day vibration exposure, latency period for appearance of the vascular disorders among tractor drivers was less than 13 years. Key words: Hand-arm vibration, tillage implements, steering wheel, health effect