FMVSS 226 Ejection Mitigation: A Review 2013-01-0469
In January 2011, the National Highway Traffic Safety Administration (NHTSA) published a final rule establishing Federal Motor Vehicle Safety Standard (FMVSS) 226 Ejection Mitigation, with the intent of reducing the occurrence of complete and partial ejections of vehicle occupants during crashes, especially rollover events.
FMVSS 226 requires component-level tests to be conducted on ejection mitigation countermeasures (e.g., rollover-activated side curtain airbags). A guided, linear impactor is used to propel a headform into a rollover-activated countermeasure at up to four locations for each side daylight opening in the vehicle, for up to three seating rows. The impact tests are conducted at two energy levels (speeds) and associated impact times: 278 J (20 km/h) at 1.5 s after curtain activation and 178 J (16 km/h) at 6 s. The FMVSSS 226 compliance criterion is that the headform cannot travel more than 100 mm past the inside surface of the side window plane. FMVSSS 226 is scheduled to begin phasing-in on September 1, 2013.
This paper provides an overview of the FMVSS 226 test procedure, and a summary and analysis of publicly-available test results conducted by the NHTSA. While 2007-2009 vehicles performed better than 2003-2006 vehicles, relative to the FMVSS 226 headform excursion criterion, none of the vehicles passed all of the tests required by FMVSS 226. Based on this fact, the majority of current-production rollover-activated side curtain airbags will require some redesign in order to comply with FMVSS 226.