Electric and hybrid vehicles are quiet … too quiet, according to the US Department of Transportation. Although the unobtrusive thrum of an EV in motion could be thought of as a positive thing, the Department’s National Highway Traffic Safety Administration (NHTSA) has announced a new safety standard that will require newly-manufactured hybrid and electric vehicles to emit artificial warning sounds to alert pedestrians to their presence.The new rule is the product of the Pedestrian Safety Enhancement Act 2010, and the process of defining the specifics has been caught up in the bureaucratic process for years. Now that it’s official, the new Federal Motor Vehicle Safety Standard No. 141 will help prevent around 2,400 pedestrian injuries per year, according to the NHTSA. The European Commission and the UN are both already considering similar regulations.