All terrain vehicle loss of control events in agriculture: contribution of pitch, roll and velocity.

All terrain vehicle (ATV) (i.e. quad bike) loss of control (LOC) events are a major cause of injury and death on New Zealand and Australian farms. ATV LOC history, work experience, anthropometric data and vehicle pitch, roll and velocity data were recorded from 30 farmers. The terrain induced 95th percentiles were forward pitch 27.8 degrees , backward pitch 28.7 degrees and 20.8 degrees for left and right roll. Nineteen participants (mean 42.4 years) had experienced 53 LOC events and were on average 9.5 years younger than the 11 participants (mean 51.9 years) who had not previously experienced LOC. Peak pitch, roll and velocity were not associated with LOC; however, at peak left roll the non-LOC group had a pitch of 3.1 degrees downhill, while the LOC group had a pitch of 2.1 degrees uphill. Results indicate ATV LOC prevalence is considerably underestimated, while increased risk for LOC may be influenced by a combination of personal, mechanical or terrain factors. The ATV pitch, roll and slope traverse data may help in the better understanding of why LOC events occur, may help in the development of safety equipment such as a tilt warning device and will contribute to national safety guidelines. STATEMENT OF RELEVANCE: Approximately 80,000 ATVs are used in rural New Zealand and ATV accidents are the single most common cause of work-related fatalities, apart from road accidents. This fieldwork research provides pitch, roll and velocity data and considers how these data might contribute to risk of ATV accidents.