To allow all pedestrians to detect vehicles that do not make sound
The U.S. Department of Transportation's National Highway Traffic and Safety Administration(NHTSA) have submitted a proposal that both hybrid and electric vehicles should emit a sound that meets the minimum standard while driving at low speeds in order to help pedestrians be more aware of the said vehicle.
"Safety is our highest priority, and this proposal will help keep everyone using our nation's streets and roadways safe, whether they are motorists, bicyclists or pedestrians, and especially the blind and visually impaired," said U.S. Transportation Secretary Ray LaHood.
Hybrid and electric vehicles normally produces minimal noise while operating at low speeds(for hybrid vehicles) as they do not rely on traditional internal combustion engines making them difficult to detect for pedestrians and even poses a greater hazard for blind and visually impaired individuals.
The proposed standard, Federal Motor Vehicle Safety Standard No. 141, would fulfill Congress' mandate in the Pedestrian Safety Enhancement Act that hybrid and electric vehicles meet minimum sound requirements so that pedestrians are able to detect the presence, direction and location of these vehicles when they are operating at low speeds.
"Our proposal would allow manufacturers the flexibility to design different sounds for different makes and models while still providing an opportunity for pedestrians, bicyclists and the visually impaired to detect and recognize a vehicle and make a decision about whether it is safe to cross the street," said NHTSA Administrator David Strickland.
The sounds emitted by the said vehicles would need to be detectable under a wide range of street noises and other ambient background sounds when the vehicle is traveling under 18 miles per hour. At 18 miles per hour and above, vehicles make sufficient noise to allow pedestrians and bicyclists to detect them without added sound.
Each automaker would have a significant range of choices about the sounds it chooses for its vehicles, but the characteristics of those sounds would need to meet certain minimum requirements. In addition, each vehicle of the same make and model would need to emit the same sound or set of sounds.
NHTSA estimates that if this proposal were implemented there would be 2,800 fewer pedestrian and cyclist injuries over the life of each model year of hybrid cars, trucks and vans and low speed vehicles, as compared to vehicles without sound.