WASHINGTON -- Another 35 million to 40 million inflators on air bags made by Japanese auto-parts maker Takata need to be replaced and are subject to new recalls that will more than double what already is the largest automotive recall in American history, the federal government said Wednesday.
The recall expansion would raise the number of inflators to be replaced to 69 million, a task that the government predicts will take until the end of 2019 to complete.
The car and truck models included in the expanded recall and the total number of vehicles will be posted on the National Highway Traffic Safety Administration's website in the coming weeks. Most of the expansion is for front passenger air bags that were not part of previous recalls, said Mark Rosekind, head of the safety agency.
"This issue is urgent," Rosekind said, urging people to get recalled vehicles fixed as soon as parts are available.
"The science now clearly shows these inflators can become unsafe over time," he said, referring to evidence that chemicals in the devices can degrade, especially when exposed to heat and humidity.
Fourteen manufacturers were already involved in the recall, and the expansion includes three additional manufacturers, Tesla, Jaguar-Land Rover and Fisker.
Takata air-bag inflators can explode with too much force and injure people. So far, at least 11 deaths and more than 100 injuries have been reported worldwide.
Replacing so many inflators will be daunting because automakers involved in the current recall of 28.8 million inflators have been able to fix only 28 percent of the cars involved after more than two years. Air-bag manufacturers have had trouble making enough replacement inflators, and automakers have had difficulty finding owners and persuading them to get cars repaired.
Under an order issued last year, the government has wide authority over Takata to prompt additional recalls.
The expansion will be phased in between this month and December 2019, with older cars and those in areas of high heat and humidity getting priority, the agency said.
Takata uses the chemical ammonium nitrate to create an explosion that inflates air bags in a crash. But the chemical can degrade over time when exposed to heat and humidity and burn too fast, blowing apart a metal canister and spewing shrapnel.
The expanded recall covers all front air bags that do not have a chemical drying agent known as a desiccant. But it does not cover side air bags without the drying agent, nor does it cover another 32 million air bags that have the desiccant.
The government and an independent expert it hired reviewed three independent investigations and confirmed findings that the problem is caused by time, airborne moisture and temperature fluctuations that can degrade the ammonium nitrate, the agency said.
"This recall schedule ensures the inflators will be recalled and replaced before they become dangerous," Rosekind said.
National Highway Traffic Safety Administration officials who briefed reporters after a news conference said vehicles under 6 years old are not currently at risk of an inflator rupture even if they are in a high humidity region. But as they age, the risk grows, especially in high humidity areas where temperatures frequently cycle from cool to very hot. Vehicles in Florida or Gulf Coast states are more at risk than in Washington, D.C., for example.
Six years is a conservative estimate, the officials said. The replacement schedule is aimed at getting vehicles fixed before they are old enough to risk a rupture.
Inflators with the drying agent have not been recalled because none has ruptured because of problems with ammonium nitrate, the safety agency said. There was one rupture, but it was attributed to a manufacturing problem with the canister, the agency has said.
Sen. Bill Nelson, Florida Democrat whose state includes several of the injuries and deaths from Takata inflators, said the pace of the recalls still isn't fast enough. "If we wait another three or four years for these to get replaced, more people are likely to die," he said.
Only a few weeks ago the safety agency said it did not have enough data to expand the recalls. But since then, the agency has received the reports pinpointing the cause, enabling it to identify vehicles at risk, the agency said.
Takata, which had resisted recalls before being fined last year by the safety agency, said it knows of no ruptures in the batch of inflators that have been added to the recalls, nor does it know of any new data or scientific analysis "that suggests any substantial risk with respect to such vehicles."
Still, Takata said, it agreed to the expansion out of a shared interest in safety.
"This agreement with NHTSA is consistent with our desire to work with regulators and our automaker customers to develop long-term, orderly solutions," CEO Shigehisa Takada said.
Even without the expansion, it would have taken until the end of 2017 for enough replacement parts to be manufactured, said Scott Upham, chief executive of Valient Market Research in Philadelphia, which tracks air-bag sales.
Upham said other makers of air-bag inflators such as TRW Automotive, Daicel and Autoliv have agreed to produce even more.
"They're pitching in to the best of their ability, but even with their help, it's going to be very difficult to really ramp up production to cover this," Upham said.
Upham said it will be difficult for Takata to survive financially with the expanded recall. He expects the company to file for bankruptcy and emerge as a smaller corporation specializing in seat belts, electronics and air-bag assemblies without inflators.
"It's very clear that the company cannot pay all the expenses at this point," said Koji Endo, a car industry analyst at Advanced Research Japan. "The question is: Is there a player that wants to save Takata?"
Potential rescuers include Japanese automakers, which have become increasingly dependent on Takata's air bags, seat belts and other parts over the years. They also could include foreign auto-parts companies that might be tempted by Takata's still-strong sales and its market share.
The additional recalls come as authorities in Malaysia investigate two more recent deaths in cars with Takata air bags that ruptured. Honda says the inflators spewed metal fragments in the crashes, but the cause of the deaths has not been determined.
Information for this article was contributed by Tom Krisher, Joan Lowy and Dee-Ann Durbin of The Associated Press; by Jonathan Soble of The New York Times; and by Chua Kong Ho, John Lippert and Jeff Plungis of Bloomberg News.
A Section on 05/05/2016
*CORRECTION: Up to 40 million inflators on air bags made by Japanese auto-parts maker Takata are subject to new recalls. The recalls can include driver- and passenger-side air bags, not necessarily 40 million vehicles. A headline misrepresented the scope of the recall.