Assessment of Hand-Arm Vibrations of Chainsaws for Urban Trees Maintenance

Abstract

Tree felling, processing, and pruning of urban trees are performed with the use of various types of manual tools or motorized chainsaws. The use of such equipment can cause the exposure of workers to hazardous physical agents, including hand-arm vibrations that can incite occupational diseases. In this work, levels of exposure to hand-arm vibrations caused by two chainsaws for pruning (one electric powered and one with an endothermic engine) and two pole chainsaws (one electric and one endothermic) were assessed. The collection of vibration data was carried out according to the ISO 5349-1:2015 standard relating to the measurement of the levels of vibrations transmitted to the hand-arm system. The instrument chain was composed of an 8-channel signal acquisition/processor, two triaxial accelerometers and an accelerometer calibrator. The two accelerometers were mounted on the equipment handles during the cutting operation. The legislation provided for the orientation of the three axes according to the basic biodynamic and/or centric coordinate systems relating to the hand. Obtained results indicated that occupational exposure, calculated in terms of daily vibration exposure A(8) to hand-arm vibrations in intermediate mechanized activities, can cause health risks for workers, especially with regard the pole chainsaws. The results showed the need for actions that can minimize transmission in activities with a level above the guidelines.