Following a year-long investigation, the Independent Testing Coalition (ITC) today validated the long-held suspicion that ammonium nitrate, the propellant used in Takata airbags, was among the causes of bursting airbag inflators that have claimed 11 lives worldwide and have injured at least 100 others. The ITC is an independent coalition of 10 carmakers that banded together to find the cause of the airbag crisis.
According to Automotive News, the coalition’s probe concluded that the propellant used by the airbag manufacturer was the key to the entire issue. When the propellant is combined with the construction of the inflators and exposure to moisture, you have the three elements needed to cause the failures. “You can’t have the energetic disassembly [burst housings] without all three factors,” David Kelly, leader of the group and former chief of the National Highway Traffic Safety Administration (NHTSA) said. “You have to have all three.” More than 2,000 inflators were tested by Orbital ATK during the investigation.
The group’s findings also validated concerns that the airbag inflator problems were exacerbated by the local climate. That’s why the early recalls were first focused on hot, muggy areas. In the U.S., the areas included the southern states, Puerto Rico, the Virgin Islands, Hawaii, Guam, Saipan and the U.S. Pacific Trust Territories. Takata said that ITC’s findings were consistent with its conclusions that were based on tests conducted by a German scientific research firm. Further, the airbag manufacturer indicated that it had “fully cooperated with ITC to support their analysis.” The spokesman continued that “we will continue to work closely with them, NHTSA and our customers to take aggressive actions that advance vehicle safety.”
The ITC tests showed that inflators were unable to shield the propellant from moisture. On exposure to moisture, the propellant begins to deteriorate. As the propellant deteriorates, the force of the blast it creates grows to the point where it shatters the inflator housing. The shattered inflator housing then scythes through the interior of the vehicle, often with deadly effect. The tests, Automotive News said, were the first to provide a scientific basis for the inflator failures. However, Kelly noted, that this is just the first step; the continuing probe is far from over. Next, probers must move beyond the four inflator designs that were tested to inflators that were not covered by any recalls. And, the investigators must look at newer versions of the inflators that not only use ammonium nitrate, but that also employ a chemical drying agent.
In the United States, the NHTSA recently expanded the recall by 5 million inflators so that the number of inflators slated to be recalled is now 29 million in 24 million cars. Reports circulated during the weekend that regulators are considering a mammoth expansion of the recall, possibly to 90 million devices. The potentially defective devices pose a risk for millions of drivers because as many as 75 million vehicles may be involved worldwide. The airbag inflator recall is now the largest safety recall in history.
ITC members include:
- Fiat Chrysler
- General Motors