Takata Corp has told U.S. safety regulators it will no longer use a volatile chemical in its air bag inflators, which have been linked to six deaths since 2008.
The Japanese supplier is at the center of a global recall of tens of millions of cars for potentially deadly air bag inflators that could deploy with too much force and spray metal fragments inside vehicles.
Use of ammonium nitrate as a propellant in Takata air bags has been connected to dozens of ruptured inflators since 2003. In addition to the six deaths, the defective inflators have been linked to hundreds of injuries. The fatalities were all in Honda Motor Co Ltd vehicles and were mostly in the United States.
The agreement to stop using ammonium nitrate was detailed by Takata executive Kevin Kennedy, in written testimony ahead of a hearing before a U.S. House panel on Tuesday.
Discovery of a root cause of Takata's air bag problems "is not imminent," according to David Kelly, head of an automakers' coalition investigating Takata air bag inflator ruptures. Kelly told Reuters last month that if a root cause cannot be found, "we may have this same discussion again" years from now.
On May 20, Takata doubled the amount of recalled vehicles in the United States to 34 million and widened the worldwide recall of air bags to 53 million vehicles. It is the biggest automotive recall in U.S. history.
Last week, seven automakers expanded their recalls of vehicles with Takata air bags.
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