The federal government this month announced a new rule requiring automakers to equip new hybrid and electric vehicles with sound alerts to protect pedestrians and bicyclists when the vehicles are moving at slow speeds. Here, a man walks beside vehicles on the lot of a Toyota dealership in Alexandria, Va. in February 2014. (EPA/MICHAEL REYNOLDS)

 Your quiet hybrid is likely to make itself heard in the not-so-distant future.

Under a new safety regulation issued by the federal government, hybrids and electric cars will be equipped with a device that emits sound to alert passersby that the vehicle is running. Manufacturers have until Sept. 1, 2019, to meet the requirement.

The National Highway Traffic Safety Administration (NHTSA), in announcing the regulation, said adding noise to the nearly soundless vehicles could prevent nearly 2,400 injuries a year to pedestrians and bicyclists.  The measure is of special importance to people who are blind or visually impaired.

“The sound is really important when you’re at an intersection because it’s really the only thing that’s telling you not only whether there are cars in the intersection or not, but what the overall pattern of the traffic is,” said Chris Danielsen, a spokesman for the Baltimore-based National Federation of the Blind, which lobbied for the measure.

Danielsen, who is blind, said sound is critical even for a person who is using a guide dog or when intersections are equipped with audio devices to help people navigate. It’s also important in parking lots, where slow-moving hybrids or electric vehicles can travel in almost complete silence.

The federal safety agency began gathering evidence of potential dangers posed by cars powered by something besides an internal combustion engine at least six years ago. In 2009, Nissan proposed adding a chime or perhaps even a futuristic whirring noise that reminded one of our colleagues of the flying machines in “Blade Runner.”

But, in a way, the rule will take the automobile industry back in time, to the days when engineers sweated over ways to silence the gas-powered engine.

Automakers will have to equip all new hybrids and electric passenger vehicles with sound alerts that operate when the vehicles travel forward at speeds of up to about 19 mph or in reverse. The agency said that at faster speeds, an artificial sound alert isn’t needed because the vehicle’s tire and wind noises can alert pedestrians.

The Alliance of Automobile Manufacturers, which represents the “Big Three” U.S. automakers and others, welcomed the rule as long as manufacturers can be flexible about the sounds that are used.

“For years and years, having a quiet car was something society wanted,” Alliance spokesman Wade Newton said. “So it’s a little different. But we agree that some people need those audible clues.”

But manufacturers are also eager to find alert sounds that will warn bystanders without annoying the vehicle’s occupants, Newton said. And, they want to create different “sound signatures” to distinguish their brands and models from one another. Ideally, the makers say, a car fanatic should be able to close his or her eyes and distinguish a German-made convertible from, say, a domestic minivan.

As for me, I’d love it if the Prius could sound like one of “Big Daddy” Don Garlits’s dragsters or a Don “The Snake” Prudhomme funny car. Failing that, maybe the sound of a hamster wheel would do.  (In the same spirit, National Public Radio a few years back suggested the Village People’s “Y.M.C.A.,” a train whistle or the gentle clip-clop of a horse.)

Danielsen, the spokesman for the Federation of the Blind, said the organization is also fine with variety and flexibility. But he said his organization also doesn’t want the car industry or consumers to get carried away.

“When we first started talking about this, a lot of people said, ‘Well, this will be great — you can have  ringtones for cars,’ ” Danielsen said. “And that’s not really what we want.”

Cars should probably sound like cars, he said. And although some variety among the brands would be fine, the organization would prefer there be uniformity by make and model, so that a Dodge Charger always sounds like a Dodge Charger, and so on.

Danielsen also said the organization understands the industry’s need to come up with sounds that alert bystanders without getting on the occupants’ nerves, but the deciding factor should be to protect pedestrians and bicyclists.

“We are all for trying not to annoy the occupants,” he said. “But, ultimately, this is a safety issue.”

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