Examination of Rollover Accident Characteristics, using Field Performance Data

Using NHTSA field performance data, this study assesses rollover injury risk to restrained and unrestrained occupants by number of quarter turns and nature of injury. The study found that over 80% of light vehicle rollovers involve one to four quarter turns, and less than 3% involve 9 or more quarter turns. The injury risk for belted non-ejected occupants in rollovers with more than five quarter turns is 2-3 times the injury risk in rollovers with less than five quarter turns. Injury risk to belted non-ejected occupants is lower compared to unbelted. Light truck occupants sustain lower injury rates in rollovers compared to car occupants. The paper also addresses some of the limitations of using NHTSA field performance data.