In an effort to make streets safer for pedestrians, the National Highway Traffic Administration (NHTSA) has proposed a rule that could require engineers to add more sound to hybrids and electric vehicles (EVs).
The proposed rule, a follow-on to the Pedestrian Safety Enhancement Act of 2010, would likely require that automakers add external speakers to hybrids and EVs. NHTSA estimates that such speaker systems would add about $30 to the manufacturing cost of the cars, but could prevent about 2,800 injuries over the life of each vehicle model year.
"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's safe to cross the street," NHTSA administrator David Strickland said in a press release.
Toyota's Prius uses a Vehicle Proximity Notification System under the hood that emits additional engine-like noises below 15mph. (Source: Toyota)
The mandate is the result of numerous studies over the past five years that have shown that the incidence of pedestrian crashes is higher among hybrids and electric cars. A 2009 study from NHTSA conducted on 8,287 hybrids and 559,703 conventional vehicles showed that hybrids were "two times more likely to be involved in a pedestrian crash." Similarly, a study done in Japan at the request of the Japanese Federation of the Blind revealed that more than half the blind respondents were "terrified" of hybrids.
NHTSA's mandate would provide leeway for automakers as to the kinds of sounds, but it does call for them to be detectable under a wide range of street noises and ambient background sounds.
Some hybrids and EVs already incorporate mechanisms for additional sound. Toyota's Prius and RAV EV vehicles, for example, employ a Vehicle Proximity Notification System (VPNS), which is located under the hood and emits sounds at speeds under 15mph. VPNS includes low- and high-frequency sounds that mimic Toyota's internal combustion engines. "It's a retrofitted little speaker behind the front grille," Jana Hartline of Toyota told Design News. "It's not anything that can be heard inside the car, but it is distinctive."
NHTSA said it will give the public 60 days to comment on the proposed mandate. Automakers are expected to work with the agency on the development of a standard. "We've studied it on our own and we will continue to work with NHTSA on it," Hartline said.
Again, I don't see any point in singling out (H)EVs here. Just legislate that vehicles should be no quieter than <N>dB. They should target the problem they're trying to address, not (H)EVs in particular.
I also find it ... odd ... that they seem to be imagining that all noise from a vehicle comes from the engine. Tire noise and air conditioners are at least as noisy as an idling engine on most small passenger cars.
I read through the press release. There is a lot of information that supports needing this.
Anecdotally, many in my area been hit by EVs and hybrids. As pedestrians, we rely on audible cues, such as deceleration, to determine safety. That's missing from EVs and Hybrids, leaving pedestrians and cyclists to completely rely on the driving skills and attentiveness of the person behind the wheel.
A Prius doesn't need to sound like a Harley to get someone's attention. There's a solution here if the emotion is taken out of the discussion.
This isn't *extra* noise as I read it, something I'm not at all fond of; this is making the same amount (more or less) of noise that gasoline engines make. Chuck, the cars are usually doing insane speeds in a 25 mph zone, on a blind curve no less. When I can't hear any coming (I have insanely good hearing), I know it's safe to do my super-fast U-ey. This will help a lot if it lets me hear them. Same goes if I'm in a garage or a parallel parking lot, where it's either hard to see or hear them coming.
I work for a company that has 80% blind direct labor. I've been wheeling my Prius around the company for several years without incident. After all, it's always been the driver's responsibility to look out for pedestrians, blind or sighted. It's not appropriate to honk your horn at a pedestrian to have them get out of the way. In effect, that's what they're proposing by including a speaker under the hood.
I'm concerned that, if they single out (H)EVs, rather than just making a general, minimum-sound-level law (which I also question the value of), then (H)EVs will end up being artificially noiser than gasoline vehicles!
Anyway, this appears to be where to comment upon this to the task panel investigating it:
I bicycle commute and when I am cruising there is so much wind noise that I can not hear most vehicles coming behind me. When I'm stopped I notice plenty of of tire noise from moving vehicles, and I've noticed that motor vehicles appear to be large enough to trigger visual clues as well.
It does seem to be a mandate without an actual cause. Is there a real danger, or does it just seem to be a good idea to pass legislation just in case it makes us all safer? It's strange how quick our country is to pass legislation on the perceived dangers of motor vehicles and how slow we are to passing legislation elsewhere when thousands of people really are being killed.
I have a 2012 LEAF wich has a nice beep-beep-beep sound when in reverse. No sound in forward though. I haven't had a problem yet but I appreciate the needs of the hard-of-hearing as we will all be that some day.
Since a safe sound is important for all cars, don't single out particular vehicle types. Just state the minimum sound level for all cars under 15 MPH that meets some 99% of peoples needs. Any car coasting to a stop can be as quiet now as an EV.
Also since loud sounds are much more of problem, mandate the max vehicle noise level for all vehicles at any speed. High noise affects everyone.
Speaking as a hybrid driver, I find this really annoying, since their quietness is a valuable feature. Also, there's no limit to how safe you can make a car, by reducing features. You can make it noisy like this, and then give it 2000lbs of safety features until it gets 5MPG and can't drive any faster than 10MPH! Plus, there wouldn't be any on the road anyway, because nobody could afford it. Thatwould be a very safevehicle!
The main thing that I think is "all wrong" about this is that they're addressing (H)EVs rather than the problem itself. They shouldn't cite (H)EVs, or even any particular speed range, and instead just say "no vehicle should be quieter than <N>dB." No value in tying it to any particular drive-train technology.
I agree. When I was kid I was told many many times "look both ways before you cross. These days people walk out in front of your car without even a glance in either direction, Often times with their eyes on their cell phones. Public awareness is the real issue, not the quiet new vehicles.
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