U.S. traffic safety regulators have proposed more seat belt reminder systems in new passenger vehicles.

The proposed National Highway Traffic Safety Administration rule would require automakers to install the reminder signals for front and rear passenger seats in vehicles of 10,000 pounds gross weight and lighter. The signals are currently required only for the driver’s seat, though the rule would also enhance those.

A visual signal after the car is started and lasting 60 seconds and an audio-visual signal while it’s operating and lasting 30 seconds would alert the driver of unbuckled rear seat belts, much longer than current driver signals last - about 10 seconds. In the front, audio-visual signals would engage until the driver and passenger seat belts are buckled.

The NHTSA says automakers could adjust frequency and volume of the signals for effectiveness and owners’ satisfaction.

The division of the U.S. Department of Transportation estimates the rule, if adopted, would prevent more than 100 traffic deaths a year and some 300 injuries. It said seat belt use is up from a decade ago but that rear seat belt use is lower than that in front seats. It said buckling up cuts risk of fatality in the rear by 55% in passenger cars and by 74% in light trucks and vans.

NHTSA Acting Administrator Ann Carlson said in a press release that half of the nearly 43,000 people who died in auto crashes in 2021 were unbuckled.

The NHTSA will take public comment about the proposed rule for 60 days.

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