Nathan Bomey

USA TODAY

Federal auto-safety regulators expect to add another 5 million vehicles to the Takata air bag recalls — partly because they have identified another death attributable to defective inflators, officials said Friday.

The National Highway Traffic Safety Administration reported that it believes a South Carolina driver was killed last month when an inflator in a Takata airbag exploded. When that occurs, victims are showered by metal and plastic shrapnel. The fatal air bag deployment occurred in a 2006 Ford Ranger pickup, making it the first death in a vehicle other than a Honda.

It's the ninth death attributed to the air bag inflators in the U.S. One death was also reported overseas.

As a result, the recall will be expanded again to include about 1 million vehicles that use the type of driver-side air bag inflator found in the Ranger. In addition, another 4 million other cars and trucks could be subject to recall because they use a different type of inflator that ruptured three times in recent tests of the Toyota RAV4, NHTSA says. Brands include Ford, Volkswagen, Audi and Mercedes-Benz.

They would be added to recalls already ordered for 23 million ammonium-nitrate inflators in 19 million vehicles in the U.S.

NHTSA spokesman Gordon Trowbridge said that before the deadly accident, testing of 1,900 inflators in the Ranger had uncovered no problems. Representatives for Ford and Takata were not immediately available for comment.

Trowbridge, in a conference call with reporters, stressed that estimates of vehicles involved in the expanded recalls is preliminary. There could be overlap with vehicles that are already under recall for passenger-side air bags.

The latest death is "a sad reminder of the immense scope of this problem and is why we need to take unprecedented steps to resolve it," Trowbridge said.

Takata, a Japanese auto supplier, agreed in November to accept penalties of at least $70 million and up to $200 million for failing to promptly disclose and fix defective air bag inflators now blamed for 10 deaths and at least 98 injuries.

Trowbridge said Friday that the number of recalled inflators could expand by "tens of millions" if Takata can't prove that the ammonium-nitrate propellant in the inflators is not responsible for the defect.

Recalls of Takata vehicles have proceeded slowly, in part because replacement inflators haven't been readily available. Also, many vehicle owners have ignored recall notices.

As of late December, some 27% of U.S. vehicle owners with a recalled Takata driver-side air bag had completed the repair. In hot, humid areas where air bags are most likely to rupture, about 34% had gotten their cars repaired.

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