Years into the largest and most complex vehicle recall in U.S. history, fewer than half of recalled Takata airbag inflators are fixed.

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The overall repair rate for driver and passenger airbags stands at about 46.8 percent, a government website shows.

The most critical warnings involve certain 2001 to 2003 Honda and Acura models, and the risks are considered highest in high-humidity regions.

The recall is so huge some phases of it will not roll out until 2019, with up to 70 million airbags affected. Currently there are an estimated 46 million defective airbag inflators under recall in approximately 34 million U.S. vehicles from 19 manufacturers, according to the National Highway Traffic Safety Administration.

About 19.6 million airbags had been repaired by late October.

"The words 'grenade' and 'ticking time bomb' accurately convey the lethal potential of these defective inflators," says a status report by an independent monitor released this week. "To date, at least 13 people in the U.S. have died from injuries inflicted by defective Takata airbag inflators."

The status report sees “meaningful progress” by automakers and regulators but finds “much room for improvement.’

In the fatalities, the report notes, the Takata airbag inflator, “instead of properly inflating to cushion the victim and prevent injury, has detonated in an explosion that tore apart its steel inflator housing and sprayed high-velocity metal shards at the victim. The victims have died from blunt head trauma, severance of the spine at the neck or extreme blood loss from lacerations to the chest, neck or face.”

Hundreds more have been seriously injured.

Visit NHSTA.gov to see if your vehicle is under recall. If so, repairs are free, but talk to your dealer to see if replacement parts are available.