The duration of occupational whole-body vibration measurements potentially influence the values of daily exposure metrics for occupational environments as per the directive of EU/2002/44/EC. This is increasingly true in environments where the vibration inputs to the human body are non-stationary or impulsive. Current literature is sparse as to recommendations that quantify applicable measurement durations. Mansfield et al. (2003) determined that measurement durations longer than 10 minutes accurately capture the root-mean-square value for normally distributed vibration. This work extends on this approach with special attention to impulsive vibration with the requirement to capture consistent vibration dose values. Whole-body-vibration measurements were performed for full working days on vehicles at work in a South African open cast mine. The impact of increasing measurement duration on the accuracy of exposure metrics (root-mean-square and vibration dose values) is investigated for data with normal and non-normal distributions. The results of this analysis advise a suitable measurement duration for WBV measurements on heavy mobile equipment (HME) in opencast mines. It was found that measurement durations greater than 30 min and 60 min are sufficient to measure whole-body vibration with measurement errors of less than 25% (sufficient accuracy) and 12.5% (preferable accuracy) respectively.
