The ITC has named three main technical factors that were all present in violent ruptures of Takata airbags linked to injuries and deaths.
Independent Testing Coalition makes key findings in recall probe
A working group of ten automakers has named three factors that must be present in order for a Takata-made airbag to rupture violently, citing the use of ammonium nitrate propellant as the main one, Automotive News Europe reports.
The Independent Testing Coalition says construction of the inflator assembly, exposure to heat and humidity, and the use of ammonium nitrate are all required to produce what the commission and the National Highway Traffic Safety Administration (NHTSA) call an "energetic disassembly."
"You can’t have the energetic disassembly without all three factors," David Kelly, leader of the ITC and former chief of the NHTSA told Automotive News Europe. "You have to have all three."
Through its research and testing the ITC has found that, aside from humidity, the ammonium nitrate propellant may also degrade due to repeated temperature swings.
Until now, U.S regulators and Takata only suspected hot and humid climates plus age in the unusually violent deployments during a crash. The recent findings have confirmed this working theory, though age may be less critical -- the latest additions to the recall list have named fairly recent vehicles.
The Takata recall has cast doubts over the use of ammonium nitrate propellant in airbags, with the industry voicing fears the propellant-driven inflators could be shunned by automakers even if not banned outright. The ITC's report notes there are several different types of airbags as well as propellants, though it did not explicitly call for phasing out ammonium nitrate.
However, U.S. safety regulators' mandate for Takata to phase out ammonium nitrate if the supplier cannot prove that it is safe may well have the effect of banning it in the U.S.