Injury reduction opportunities of far side impact countermeasures

Over 17,000 non-struck or far side occupants in side and rollover crashes are seriously or fatally injured annually in the US. Although no legal or rating tests exist for far side crashes, test methods including appropriate dummies as well as countermeasures have been recently suggested. The aim of this study was to establish the incidence and risk of injury / fatality as a function of vehicle change in velocity (Deltav) for the most frequent injuries of belted, far side occupants in side impacts. The study was based upon the NASS/CDS 1995-2006 records of 5,653 occupants exposed to a far side crash. 401 of these were seriously or fatally injured. Combining this data with new and previously published crash test results, the potential opportunities of various concepts of far side countermeasures were evaluated. Head/thorax injuries caused by interaction with the struck side interior were found to dominate. Countermeasures such as side support airbags and altered three-point belt geometry (e.g. four-point belts) are relevant for Deltav of at least 20-30 km/h. The opportunity for mitigating AIS3+ injuries in these severity ranges was found to be 19%- 57%. Countermeasures such as struck-side curtains are able to provide cushioning at Deltav 30 to 50 km/h, which would cover almost a third of all fatalities.