The US Transport. Dept. “quiet car rule” for electric cars
When hybrid-electric cars came to the market in 2000, the concept of having noisemakers added to vehicles began. Organizations representing the blind have been raising concerns that cars operating on electric power at low speeds could not be heard by pedestrians who also could not see them. The Department of Transportation’s NHTSA concluded the rules under which those quiet cars will be expected to emit noise at low speeds. The full compliance with the rule was extended to 2020 by the department.
In 2010, Congress had mandated the agency to research, investigate, and propose rules to attach noise-emitting gear to quiet cars and set them in force in 2014. The new rules require that all vehicles make noise at speeds of up to 18.6 miles per hour (30 km/h) by September 2020. One year before that, carmakers fitted the noise-makers to 50% of the qualifying cars.
According to NHTSA, the combination of noise from wind resistance and tires make cars easier to hear, at speeds above that level. A request to lower the threshold speed to 12.4 mph (20 km/h) by Nissan was rejected. Automakers also requested that they be allowed to modify the noises legally emitted by their cars to adopt unique sounds that aligned with their brands and the agency is considering that request. NHTSA said that when fully implemented, it expects the noise-making rules to prevent 2,400 injuries a year.
The agency estimates that by 2020, the rules will apply to more than half a million vehicles, which represents a projection of the number of battery-electric, hybrid and plug-in hybrid vehicles that will be sold that year. There is sparse data on the rate of injuries sustained by pedestrians who do not hear approaching cars, but the problem may now have increased beyond the blind to those who do not watch what is happening in the streets but down to their mobile devices while walking.