The government is adding automatic braking to its five-star safety rating system designed to help consumers identify the most important safety technologies to look for in new cars.
The National Highway Traffic Safety Administration said automatic braking will be added to the ratings beginning with 2018 model cars.
The agency announced in September that it had reached voluntary agreements with 10 automakers to include the technology as standard in new cars, but offered no timeline.
The systems use sensors to warn of an imminent collision and, if the driver does not apply the brakes, engage the brakes automatically.
Accident investigators estimate automatic braking could prevent or mitigate an estimated 80 percent of rear-end collisions that cause about 1,700 deaths and a half-million injuries annually.
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