The US Department of Transport’s NHTSA is proposing that hybrid and electric vehicles meet minimum sound standards in order to help make all pedestrians more aware of the approaching vehicles.

“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.

The sounds would need to be detectable under a wide range of street noises and other ambient background sounds when the vehicle is travelling 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.

See also: FEATURE: Sounds for driving