The National Administration of the US traffic (NHTSA) has adopted a law, according to which from 1 September 2019 all sold in the United States electric cars and hybrid vehicles will be required to issue warning signals when driving at speeds below 30 km/h. According to officials, this innovation will protect pedestrians who may fall under the wheels virtually silent hybrids and electric cars. Note that such a bill has been approved by the US Congress back in 2010 under the Act on the improvement of pedestrian safety. Officially, it was to be taken in the 2014th, but after the introduction of amendments postponed over and over again. NHTSA experts noticed that the chosen speed limit is 30 km/h is not accidental. According to them, at higher speeds it becomes clearly audible aerodynamic noise, and the sound of the tires, so pedestrians can promptly learn about upcoming cars, no matter how quietly did not work their technical stuffing. According to forecasts of the NHTSA, the bill will reduce the number of injuries to pedestrians by about 2 400 cases per year, although it is worth noting that some manufacturers of electric and hybrid models are fitted with their respective audible warning device now (for example, the Kia Soul the EV and the Nissan Leaf ).