By Paul Lienert and David Morgan
WASHINGTON/DETROIT (Reuters) - Takata Corp will "rapidly" reduce production of a volatile chemical that has been linked to ruptured air bag inflators, a company executive told U.S. lawmakers on Tuesday.
The chemical, ammonium nitrate, "appears to be one of the factors" contributing to inflator ruptures linked to six deaths and hundreds of injuries, Kevin Kennedy, executive vice president of Takata subsidiary TK Holdings, said.
Kennedy told a House subcommittee that Takata has "alternate propellants now with guanidine nitrate. We started production a year or two ago, and we’re continuing to ramp those up. I think overall you will see our production of ammonium nitrate go down rapidly."
Takata is the only major air bag manufacturer using ammonium nitrate as an air bag propellant. Kennedy said Takata plans to continue using ammonium nitrate, including a newer version of the compound that does not react as violently to moisture.
However, the company is still supplying some automakers with an older inflator and propellant that uses an earlier version of the compound. The older-style inflators also have been installed as replacement parts in an unspecified number of vehicles over the past year and may have to be replaced by newer designs, Kennedy said.
Representative Michael Burgess, the Texas Republican who chaired Tuesday's House subcommittee hearing, said he "couldn't believe what they were telling me."
"They are still making an air bag with ammonium nitrate as a propellant without a desiccant and they're putting that in replacement vehicles and new vehicles," Burgess said. "It almost seems like there should be a warning label stamped on the car."
Kennedy said Takata has been buying replacement inflators from competitors TRW Automotive Inc [TRWTA.UL] and Autoliv Inc (ALV.N), both of which use guanidine nitrate.
Last month, half of the replacement inflators that Takata shipped to automakers came from TRW and Autoliv, Kennedy said, adding that the figure will rise to 70 percent by the end of the year.
Kennedy said Takata has shipped 4 million replacement inflators to automakers.
Earlier on Tuesday, the top U.S. auto safety regulator said that some of those replacement parts may not offer consumers a remedy that lasts the life of the car.
Many cars equipped with older Takata air bag systems could have to be fixed more than once, said Mark Rosekind, head of the National Highway Traffic Safety Administration.
He told a House subcommittee on Tuesday that his agency is still sifting through more than 2.4 million pages of documents from Takata, and has not determined why some of Takata's air bag inflators explode.
As a result, Rosekind said, parts being produced to fix more than 30 million vehicles included in a recall NHTSA ordered last month may themselves have to be replaced.
Lawmakers repeatedly asked Rosekind when owners of affected vehicles can be sure that their air bags are safe.
Because of the size and scope of the recall, which now covers about 13 percent of U.S. cars on the road, "a replacement part may not be immediately available" for some owners, Rosekind acknowledged.
Lawmakers wanted to know if those replacement parts are different enough from the original parts that they will not experience similar defects over time.
Rosekind in turn urged support for the proposed Grow America Act, which would give NHTSA more budget and greater oversight over safety defects, and would raise the maximum penalty that NHTSA could levy on car companies and suppliers to $300 million from $35 million.
Rosekind said NHTSA plans a public hearing this fall on the Takata air bag issues.
Those issues have taken on increasing urgency this year as Takata has continued to expand the list of potentially defective air bags.
The inflators in those air bags are prone to rupture and send shrapnel into vehicle occupants. They have been linked to hundreds of injuries, according to NHTSA.
Ten passenger-car manufacturers since 2008 have announced recalls involving ruptured inflators in Takata air bags, and their dealers have been replacing the affected parts as they have become available from the company and, more recently, other suppliers.
Another complication is that the recall involves both driver- and passenger-side air bags. Neither Takata nor NHTSA can say how many vehicles in total may be affected or how much overlap there may be.
(Reporting by Paul Lienert in Detroit and David Morgan in Washington; Editing by Steve Orlofsky and Chris Reese)