NHTSA "quiet car" rules to require hybrid, electric cars to make sounds by end of 2020

Hybrid and electric cars will sneak across parking lots for a few more years. The NHTSA on Monday set a long-delayed deadline for automakers to add sounds to otherwise nearly silent hybrid and electric cars: September 2020.

The NHTSA says that automakers will need to fit "alert sounds" to vehicles operating under nearly silent electric power when they drive at speeds of around 18 mph or slower. Electric and hybrid car motors make little noise, unlike gas and diesel-powered cars. At higher speeds, tires on hybrid or electric cars are loud enough to surpass the NHTSA's "quiet car" rules.

The rules will be phased in until the deadline. By September 2019, automakers will need to fit noisemaking devices to at least half of their electrified cars. A year later, all new electrified cars will need the features. The NHTSA is also considering allowing automakers to install adjustable noisemaking devices that could make different sounds at the driver's command.

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The deadline for automakers comes a decade after Congress first implored the NHTSA to create rules governing the sounds that electrified cars make at low speeds. After first being outlined in 2016 by former President Barack Obama's administration, the "quiet car rules" were put on hold by President Donald Trump's administration to review petitions from automakers.

Nissan, in particular, argued that the alerts were only necessary at speeds of up to 12.4 mph.

However, the NHTSA says that while the rules will cost automakers about $40 million annually in order to fit waterproof external speakers, the noisemakers could prevent 2,400 injuries annually by 2020. The NHTSA expects automakers to sell about 530,000 hybrid and electric cars that would require soundmaking devices in 2020.