A story in today’s Washington Post entitled "The Deadly Silence of the Electric Car" discusses automakers’ views about whether and how to add noises or "distinctive audio signatures" that will alert pedestrians to the presence of battery-powered electric cars that are virtually silent at low speeds, before the internal combustion engine kicks in with its familiar noise. Some manufacturers plan to maintain the silence that has been a manufacturing goal for decades; others are experimenting with a variety of sounds that will serve as safety alerts.
The National Highway and Traffic Administration is studying the issue, and some legislators are apparently proposing measures that would mandate audio alerts.
I don’t know how this debate will affect public policy, but meanwhile it seems clear that operators of these cars need to alter their driving habits to take into account that pedestrians may not be aware of their presence. When turning across pedestrian crosswalks and driving through metropolitan areas of high foot traffic, hybrid drivers need to assume that "they don’t hear me" and drive with caution. And maybe the horn needs to be used a little more often.