Electric car fans have long been skeptical of government plans to install noisemakers to alert pedestrians to a car's presence--and now automakers are pushing for a different rule.
The NHTSA wants electric and hybrid vehicles to emit a noise at speeds of up to 18.6 mph, while automakers want it to be capped at no more than 12.4 mph.
The current noise regulations would make vehicles running on electric power too noisy--enough for the low-speed sound to be irritating to passengers travelling in the car.
According to The Detroit News, an industry group made up of the Big Three automakers, Volkswagen, Toyota, and several asian and European companies, says the noise levels would be so great under the NHTSA's proposal that some gasoline sports cars wouldn't even pass mandated noise tests at the same speeds.
The group adds that at speeds above 12.4 mph, tire noise becomes dominant anyway, making even the quietest of vehicles more audible.
The regulations would come into force from September 2014, but automakers want the rules to be either changed before then, or to have the phase-in scrapped and deferred to 2018. The NHTSA estimates a per-car cost of around $35, amounting to a cost of $23 million in the first year--though the group of automakers says the actual figure could be five times greater.
Other concerns include the NHTSA's decision for the vehicles to produce a noise at very low speeds or even at a standstill--which creates noise pollution, according to automakers.
Worse still, it could even mask the sound of a traditional car approaching, negating the apparent safety benefits of adding noise to silent cars.
Noisemakers are designed to alert pedestrians and cyclists to the presence of an electric-powered vehicle, which are generally very quiet. The sounds are designed to be distinctive over typical background noise, making them easily identifiable as vehicles.
The NHTSA estimates that the odds of an electric vehicle or hybrid being involved in a pedestrian impact are 19 percent higher than average, and 38 percent higher for a bicycle accident. Tests from around the world have so far been inconclusive on the issue.
It's likely that we'll still have noisemakers fitted to future electric and hybrid vehicles--but the noises those cars make will be hotly debated for some time to come.