Experiments by psychologist Lawrence Rosenblum of the University of California at Riverside found that subjects listening to recordings of combustion-engine vehicles approaching at 5 mph—with traffic noise mixed in to simulate a parking lot—could detect its familiar rumble at a distance of 28 feet. They couldn’t detect a Toyota Prius going that speed until it was just seven feet away. The work was funded by the National Federation of the Blind, but Rosenblum says quiet cars also pose a risk to small children, the elderly, cyclists and runners.
Pending approval in Congress, the Pedestrian Safety Act would require the National Highway Traffic Safety Administration to study the minimum decibel level required to alert the blind and other pedestrians to motor vehicles, including high-end gas-powered cars. If the act is passed, the Secretary of Transportation must set a new standard within 90 days of the study’s completion, to go into effect two years later.
A better way to protect pedestrians, some hybrid drivers suggest, is to require collision-avoidance systems or front-end airbags on all cars, although these are more complex and expensive than noisemakers. If hybrids must emit sounds, some argue, consumers should be allowed to customize them like cellphone ringtones. The company Better Place, which is developing networks for recharging electric vehicles, has already copyrighted the term “drivetones.”
So what do you think?