AN INVESTIGATION OF OCCUPANT INJURY IN ROLLOVERS: NASS-CDS ANALYSIS OF INJURY SEVERITY AND SOURCE BY ROLLOVER ATTRIBUTES

This paper investigates the circumstances surrounding vehicle rollover and the injuries resulting from this type of vehicle crash mode. Data was extracted from the NASS CDS database for the years 1997-2000. Crash events with at least one occupant and with at least one injury of AIS 3 or higher were studied, and all injuries with an AIS value of 3 or more were examined. The frequency of rollover events was examined by vehicle type, model year, occupant position, number of quarter turns, direction of roll, roll initiation source, roll location relative to the roadway, and extent of roof intrusion. Rollover exposed occupants were examined by distribution of MAIS, safety belt usage, extent of ejection, and proximity to the roll direction. Occupant injuries were examined by safety belt usage, body region injured, injuring contact/source, and extent of roof intrusion. Most data has been distributed by vehicle type. Results indicate head injuries (including face and brain) account for 45% of all AIS 3+ injuries. Head injuries associated with roof contact were the most frequent injury-source combination for all vehicle types. For all AIS 3+ injuries, 57% occur at roof deformations greater than the allowable limit of the FMVSS 216 standard. For head injuries associated with the roof, 81% occur when this deformation limit is exceeded. The highest opportunity area for mitigating injuries to belted and unbelted occupants was to the head and neck. The highest opportunity area for mitigating injuries by contact/source for belted occupants is associated with the roof and interior surfaces. For unbelted occupants, exterior contacts are the predominate injury source. For the covering abstract see ITRD E825082.