The United States Department of Transport’s National Highway Traffic Safety Administration (NHTSA) has proposed minimum sound standards for vehicles capable of driving without an internal combustion engine. It believes this could prevent 2,800 pedestrian and cyclist injuries per year, as well as saving 35 lives.

U.S. transportation secretary Ray LaHood said: ‘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.’

Federal Motor Vehicle Safety Standard No. 141 will require vehicles to make a noise which is detectable over background sounds when travelling under 18mph, including when it is stationary or reversing. The NHTSA believes tyre and wind noise above this speed is enough to warn pedestrians that they are nearby.

Carmakers will be able to choose from a range of different sounds, provided they meet the standard, but each make and model will be required to emit the same sound, or sequence of sounds.

NHTSA administrator David Strickland explained: ‘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.’

The proposal was sent to the Federal Register on the 7^th January, and members of the public have 60 days to submit comments. Final rulings will be in place by the 4^th January 2014, beginning a three-year phase-in with manufacturers.