NHTSA wants faster Takata repairs; still no root cause identified

The National Highway Traffic Safety Administration has stepped up pressure on automakers to quickly complete Takata recall repairs.

Less than one in four recalled vehicles have received new airbag modules across the country. The rate is slightly better in regions of high absolute humidity, approaching 30 percent.

“It is important to remember that vehicles in the high absolute humidity region are at the highest risk of an inflator rupture,” the agency warns, according to quotes published by The Detroit News. “And that risk goes up as the vehicle gets older. So it is critical that remedy completion rates in this region go up, and do so quickly.”

Despite the apparent link between inflator ruptures and humidity, which is believed to degrade the ammonium-nitrate propellant over time, the agency suggests a final root-cause determination remains elusive.

Whatever the cause, exploding inflators have been associated with at least 98 shrapnel injuries and eight deaths. The agency points out that nearly one in 10 inflator ruptures has resulted in a fatality, and approximately 0.4 percent of inflators pulled from recalled cars have ruptured in Takata’s test program.

“Something that’s been seen in those tests but is not yet understood, is that driver inflators and some types of passenger inflators rupture at a rate of about 1 to 2 ruptures for every 1,000 ballistics tests but other passenger types are rupturing at rates of 10 to 20 ruptures for every 1,000 ballistics tests, roughly 10 times more often,” said NHTSA investigator Scott Yon.

The agency has used the test data to group vehicles by repair priority, placing emphasis on quickly replacing the most dangerous inflators in vehicles that are registered in humid states.

Approximately 20 million vehicles have been listed in the campaigns so far, but Takata is still pursuing an active investigation into potential problems with Takata airbags used in other vehicles by other automakers. Officials have asked Daimler, Jaguar Land Rover, Tesla and other companies to detail their use of Takata components and comment on any recalls that may be under consideration.

“Given the size and complexity of this problem, and our current understanding of what seems to cause the problem, we may also need to expand the recalls in the future to cover even more vehicles,” the agency said.