Silence Isn’t Golden When It Comes To Electric Vehicles
If you’ve stood on a street corner while a hybrid car zipped silently by, you might have wondered about the safety ramifications of vehicles that emit barely a sound when driving on battery power at low speeds.
While a reduction in noise pollution is certainly a plus, particularly in large metro areas, pedestrians, bicyclists and even other drivers rely on the sound of a car’s motor to alert them to its presence. People who are visually impaired are even more reliant on the sound of an approaching vehicle. Stepping out into the roadway because you think the coast is clear can have dire ramifications.
The U.S. Department of Transportation’s National Highway Traffic Safety Administration (NHTSA) http://www.nhtsa.gov/ aims to do something about the safety concern with a proposal under the Pedestrian Safety Enhancement Act (PSEA) that mandates hybrid and electric vehicles meet minimum sound standards to alert people to their approach.
“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 NHTSA estimates that pedestrian and bicyclist injuries will be reduced by 2,800 during the life of hybrid and electric vehicles.
According to NHTSA statistics, electric and hybrid vehicles are 37% more inclined to hit pedestrians and 66% more likely to hit bicyclists than gasoline powered cars when they’re traveling at low speeds. At speeds over 35 mph, when the vehicles are noisier; they have the same rate of collision with bicyclists and pedestrians as regular vehicles.
A review of the 2012 Ford Focus Hybrid in the New York Times http://www.nytimes.com/ noted that “Battery-powered cars are intrinsically quiet, the motor sound falling between a whir and a whisper, but the Focus is deep-space silent, the quietest of the many electric cars I’ve driven.” That quietude will soon change.
Manufacturers of hybrid and electric vehicles will have leeway to design a variety of sounds for their vehicles, as long as they met sound standards that are detectable alongside street noise and ambient sounds when traveling under 18 miles per hour. At speeds over 18 MPH, the vehicles make enough noise to alert people to their approach without added sound.
In a whimsical effort to gather public input about possible sounds to install in hybrid and electric vehicles, NPR http://www.npr.org/ issued a call-out to listeners for suggestions. The most popular suggestion was the sound the Jetson’s flying car made in the 1960s cartoon series. Other suggestions included the sound of playing cards attached to bicycle spokes, the noise of a skateboard, the Beatles song, “Baby You Can Drive My Car” (beep beep, beep beep, yeah!), and the sound of Kermit the Frog singing, “It’s Not Easy Being Green.”
The NHTSA has come up with some less humorous suggestions for acceptable sounds to install in the vehicles, some of which are the current noises that a variety of existing gas-powered vehicles make at low speeds. To hear their suggestions, go to http://www.nhtsa.gov/SampleSounds.