Injury Risk Assessments Based on Dummy Responses

Abstract

Injury assessment reference values (IARVs) were developed by Mertz^{1, 2} in 1978 to assess the efficacy of General Motors (GM) restraint system designs under a variety of simulated frontal accident conditions using the Hybrid III midsize adult male dummy as the vehicle occupant. These design limit values were chosen such that if an IARV was not exceeded in the prescribed test, then the risk of the associated injury would be unlikely. “Unlikely” was defined as risk levels less than 5%. Since injury risk curves for the various dummy responses did not exist, the limit values that were chosen for the IARVs were simply conservative estimates of response values that would be consistent with the unlikely definition. These IARVs were published in 1984 as part of the GM petition of the National Highway Traffic Safety Administration (NHTSA) to allow the use of the Hybrid III midsize adult male dummy in Federal Motor Vehicle Safety Standard (FMVSS) 208 testing. In 1993, IARVs were published for response measurements of the Hybrid III small female and large male adult dummies.^3,4 These values were obtained by applying constant failure stress scaling to the Hybrid III midsize male IARVs, taking into account size differences.^5,6 IARVs have also been developed for the response measurements of the child restraint air-bag interaction (CRABI) and Hybrid III child dummies.^7–10 For these IARVs, variations in tissue strength with age as well as size were considered in the scaling relationships. A summary of all the IARVs defined for the CRABI and Hybrid III family of dummies as well as the midsize male side impact dummies (SID, EUROSID-1, and BIOSID) are given in Chapter 4, Tables 4.6, 4.7 and 4.8.