By CBSMiami.com Team

MIAMI (CBSMiami) – New federal regulations will require all new cars to be equipped with an alert system aimed at preventing hot car deaths.

The advocacy group Kids and Cars said on average 39 children die in hot cars each year.

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The new provision in the infrastructure law requires automakers to install back-seat alert systems in all new vehicles.

General Motors already has one in most models. Shad Balch with Chevrolet says the “rear-seat reminder is activated just by opening the door.”

“So, the back door opens and the car assumes you’re putting something back there,” Balch explained.

The reminder kicks in at the end of the drive.

Balch said when you power off the vehicle, a message reminding you to look in the back seat appears on the dashboard and you hear chimes.

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Balch said the goal is “to get the driver’s attention as they’re getting out of their vehicle, to take one last look at the back seat.”

Some of Hyundai’s SUVs go a step further and are equipped with motion detectors.

“It’s an ultrasonic sensor that looks for motion inside the cabin,” said Hyundai’s Chief Safety Officer Brian Latouf.

During a test with a person sitting in the back seat of a locked car, the horn and lights went off and the driver got an alert on their mobile phone when there was motion in the back seat.

“We’ve gotten some strong positive responses to it, and we think it’s the right thing to do,” Latouf said.

It’s not yet known when the rear-seat reminder mandate will go into effect.

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The law gives the Department of Transportation two years to implement the new rule.

CBSMiami.com Team