Whole body vibrations during field operations in the vineyard

Abstract

Human exposure to mechanical vibration can be a significant risk factor for exposed workers and this also occurs in the agricultural sector, in particular with reference to the driver of the tractor during field operations. The aim of this paper is the evaluation of Whole Body Vibrations for the operator driving tractors during the field operations in the vineyard. The experimental tests were performed using a wheeled and a track-laying tractor. They were coupled to four different machines: rototilling (RT), chisel plough (CP), flail mowers (FM) and vibro farmer (VF). Two homogeneous plots of vineyard, about 200 m long, were identified different only for slope: 0% and 30%. The tests were performed during the execution of the cultivation operations in flat conditions, uphill and downhill. For the evaluation of whole-body vibration we referred to ISO 2631-1:2008 standard. We used the portable vibration analyzer HD2070 by Delta Ohm, Italy. The mean square frequency-weighted acceleration [m s -2 ] was evaluated along each of the three axial components of the acceleration vector (awx, awy, awz)The vibration total value to which the body is exposed (av) was determined by the following relationship: av = (kx 2 awx 2 + ky 2 awy 2 + kz 2 awz 2 ) 1/2 where kx = ky = 1.4 and kz = 1.The study allowed to point out that during the use of the above mentioned operating machines coupled both with a track-laying tractor and a wheeled tractor, A(8) values were always higher than 0.5 m s -2 therefore, included in the "risk threshold" identified by the Italian Law Decree 81/2008. The machines coupled to the wheeled tractor always registered higher vibration values on the driving seat than the same machines coupled to the tracklying tractor. The operating machines showing higher vibration values are rototilling and vibro farmer in both tractors. Finally, the soil conditions in terms of slope caused no particular differences of vibration levels for all the machines used in the tests.