Whole-body vibration experienced by haulage truck operators in surface mining operations: a comparison of various analysis methods utilized in the prediction of health risks.

Whole body vibration (WBV) was measured on eight surface haulage trucks in three size classes (35, 100, 150ton haul capacities). Vibration was measured at the seat/operator interface in accordance with the ISO 2631-1 standard during 1h of normal operation. Highest acceleration readings were observed in the z-axis (vertical). Estimated equivalent daily exposure values in the range of 0.44-0.82 ms(-2) were observed using the frequency-weighted r.m.s method and 8.7-16.4ms(-1.75) using the vibration dose value method. Assessment was carried out using ISO 2631-1 and 2631-5. Operators of surface haulage trucks are regularly exposed to WBV levels that exceed safety limits as dictated by the ISO 2631-1 standard. However, according to ISO 2631-5 the probability of an adverse health effect remains low. These findings confirm an apparent disagreement between the two analysis methods.