Operator whole-body vibration exposure of wheeled forwarder with bogie tracks

Abstract

Exposure to whole-body vibration (WBV) is one of the common occupational risk factors for the operators of self-propelled machinery including forwarders. It leads to the problems of lower back pain while long-term exposure causes occupational musculoskeletal diseases. Level of the total vibration exposure is the product of multiple factors, which include forwarder properties, terrain, forwarding distances, driving style and others. The aim of this study was to evaluate and compare the difference in operator whole body vibration in the full cycle of wood extraction using a wheeled forwarder and wheeled forwarder with tracks. The results were collected measuring the vibration acceleration on the seat of a brand-new forwarder. The results show that the vibration levels were slightly lower when the forwarder was operated with tracks. The calculated average A(8) exposure of the wheeled forwarder was 0.46 m·s-2 compared with 0.33 m·s-2 when the wheeled forwarder was operated with tracks. The results, however, show that the highest whole-body vibration is, when the logs are being transported to the unload location and when the empty forwarder travels back to the site unloaded. These results reveal that long transportation distances are not desirable not only from the productivity point of view, but also might have bigger harm on the operators’ health.