Reducing whole body vibration in forklift drivers.

Forklift drivers in warehouses are often exposed to whole body vibration (WBV) during the total day. There is however an association between working as a forklift operator and the development of low back pain. In this study the exposure to WBV was measured in five forklift drivers who performed a standardised order picking task during 10 minutes. The effect of driving surface (uneven concrete vs. new flat concrete), driving speed (15 km/h vs. 8 km/h) and seat suspension (mechanical suspension vs. air suspension) was investigated. Improving the driving surface was the most effective preventive measure by reducing the whole body vibration with 39%, from 1.14 to 0.69 m/s2. Lowering the speed limit resulted in a reduction of WBV with 26% (1.05 vs. 0.78 m/s2). An air suspension seat was 22% more effective compared to mechanical suspension (1.02 vs. 0.80 m/s2). On uneven concrete an air suspension seat performed even better by reducing the WBV by 29% (1.33 vs. 0.95 m/s2). A combination of a new driving surface, limiting the maximum speed and the introduction of an air suspension seat reduced the whole body vibrations below the action limit of 0.5 m/s2 as mentioned in the European directive. None of the interventions were effective enough on their own.