Comparing the Whole Body Vibration Exposures across Three Truck Seats 2017-01-1836

Whole-body vibration (WBV) is associated with several adverse health and safety outcomes including low-back pain (LBP) and driver fatigue. The objective of this study was to evaluate the efficacy of three commercially-available air-suspension truck seats for reducing truck drivers’ exposures to WBV. Seventeen truck drivers operating over a standardized route were recruited for this study and three commercially-available air suspension seats were evaluated. The predominant, z-axis average weighted vibration (A_w) and Vibration Dose Values (VDV) were calculated and normalized to represent eight hours of truck operation. In addition, the Seat Effective Amplitude Transmissibility (SEAT), the ratio of the seat-measured vibration divided by the floor-measured vibration, was compared across the three seats. One seat had significantly higher on-road WBV exposures whereas there were no differences across seats in off-road WBV exposures. The SEAT values, calculated over the whole route (which was predominantly on-road) indicated that one seat reduced WBV exposure by 9% on average and the other two seats had nearly double the attenuation performance based on A(8) exposures. The performance differences across seats may have important practical implications for truck procurement and overall truck driver health. The higher performing seats nearly doubled the amount of time drivers could operate their trucks before reaching the daily vibration action limits recommended by the International Organization for Standardization. Seat suspension-based design differences are thought to account for the performance differences.