What's wrong with electric cars? They're just too darn quiet. But not for long.
It was six years ago when Congress passed a law saying electric vehicles need to start making sounds so pedestrians – especially those who can't see well – know a car is coming.
Finally on Monday the National Highway Traffic Safety Administration (NHTSA) announced a new rule is in place, requiring electric cars and hybrids to be audible by September of 2019.
The requirement from NHTSA, which is part of the Transportation Department, says the cars have to make a sound when they're moving less than 20 mph and when they're in reverse. At faster speeds, their tire and wind noise are enough for people to hear them.
NHTSA Administrator Dr. Mark Rosekind said ""With pedestrian fatalities on the rise, it is vitally important we take every action to protect the most vulnerable road users."
Are more people getting hit by cars?
In recent years, yes.
The Insurance Institute for Highway Safety says the long-term trend is downward – pedestrian deaths are down 35 percent since 1975, they say. They suspect that's largely because people aren't walking as much, especially kids.
But from 2009 through 2014 pedestrian deaths were up 19 percent, the institute says.
The institute says it studied insurance claims from 2002 through 2010 and found hybrid cars were 20 percent more likely than conventional ones to injure a pedestrian.
The National Federation of the Blind, which put out a statement applauding the new sound requirement, says some studies suggest electric and hybrid vehicles are up to 35 percent more likely to hit a pedestrian and 57 percent more likely to hit a bicyclist.
What kind of sound will they make?
For the most part, that remains to be seen.
The Alliance of Automobile Manufacturers said Monday it's important to give carmakers flexibility about what they'll sound like. They say the sound needs to be something that won't annoy people inside the car.
CNET notes there are already a couple of electric vehicles on the market that make sounds.
The Nissan Leaf makes a high-pitched whir, which you can hear in the video below.
The Leaf has been making the sound since 2011. There's background on it here.
The Kia Soul electric vehicle went a different route. Their car makes a sound that mimics a regular old combustion engine. Kia says it also helps drivers hear how the car is accelerating.
Reuters says NHTSA has estimated that complying with the new rule will cost the auto industry about $39 million a year.
But the agency also estimates it will prevent about 2,400 pedestrian accidents per year, which would be a cost savings of $250 million or more, they say.