Whole-body-vibration (WBV) exposure levels experienced by transport truck operators were investigated to determine whether operator's exposure exceeded the 1997 International Standards Organization (ISO) 2631-1 WBV guidelines. A second purpose of the study was to determine which truck characteristics predicted the levels of WBV exposures experienced. The predictor variables selected based on previous literature and our transportation consultant group included road condition, truck type, driver experience, truck mileage and seat type. Tests were conducted on four major highways with 5 min random samples taken every 30 min of travel at speeds greater than or equal to 80 km/h (i.e. highway driving). Results indicated operators were not on average at increased risk of adverse health effects from daily exposures when compared to the ISO WBV guidelines. Significant regression models predicting the frequency-weighted RMS accelerations for the x (F(sub 5,97) = 8.63, p less than 0.01), y (F(sub 5,97) = 7.74, p less than 0.01), z (F(sub 5,61) = 9.83, p less than 0.01) axes and the vector sum of the orthogonal axes (F(sub 5,61) = 13.89, p less than 0.01) were observed. Road condition was a significant predictor (p less than 0.01) of the frequency-weighted RMS accelerations for all three axes and the vector sum of the axes, as was truck type (p less than 0.01) for the z-axis and vector sum. Future research should explore the effects of seasonal driving, larger vehicle age differences, greater variety of seating and suspension systems and team driving situations. (Author/publisher)
Samenvatting