Whole Body Vibration Exposure During Operation of Rice Combine Harvester under Egyptian Field Conditions

Abstract

The main target of this investigation is to study the effect of different working conditions during rice harvesting on the combine harvester operators WBV exposure under actual Egyptian field conditions. Data were measured and collected for four types of rice combine harvester and three methods of planting; manual transplanting, mechanical transplanting and direct sowing. Sixteen representative healthy rice combine harvester operators were selected for this study. Parameters of frequency-weighted vibration acceleration in root mean square (RMS), vibration dose value of weighted r.m.s acceleration, (VDV(8)kZ), heart pulses rate (HR), blood pressure (BP), work related body pain (WRBP), stand height and weight of operators were evaluated. Vibration measurements were performed according to (ISO 2631-1: 1997). Field experiments were conducted in a statistically designed layout (completely randomized design) and were conducted at the applied research farm of RiceMechanizationCenter, Meet Eldeba, Kafr El-Sheikh governorate and other farms beside, in the 2016 grown seasons of rice crop. The obtained results indicated that the yanmer combine harvester used for the field planted by manual transplanting at soil moisture content of 20.38 % recorded the highest WBV data of the vibration dose value of weighted r.m.s acceleration, VDV(8)kZ magnitude, while the largest single orthogonal axis is in the axis (Z) which exceeded both of exposure action and exposure limit values. This causes a high risk on the operator body which increases the heart rate and blood pressure, followed by the Daedong combine harvester for the field planted by manual transplanting at soil moisture content of 20.42 %. On the other hand, the WBV parameters recorded the lowest values for Claas combine harvester used in the field planted by direct sowing at soil moisture content of 20.67 %., consequently there is no risk on the operator and also the heart rate and blood pressure. Using rubber spring during rice harvesting by yanmer combine harvester results in a decrement percentages in the WBV values and so heart rate and blood pressure. The maximum WRBP values were obtained during harvesting rice by yanmer combine harvester for the field planted by manual transplanting, followed by harvesting rice by Daedong combine harvester for the field planted by manual transplanting and harvesting rice by Class combine harvester for the field planted by direct sowing the recorded WRBP values were 13.1, 12.4 and 6.6 (Borg scale CR—10 scale.) respectively. Results showed that there are significant differences between the frequency-weighted RMS acceleration, vibration dose value of weighted r.m.s acceleration, VDV(8)kZ, heart rate and blood pressure during studied different farm operations.