Questionable Benefits: NHTSA Proposed Rule Mandates Noisy Cars Open Access
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The National Highway Traffic Safety Administration recently published a proposed rule that would require hybrid and electric vehicles to make a minimum amount of sound while being operated at speeds slower than 18 miles per hour. Because they use an electric motor, hybrid and electric vehicles generate less noise than other vehicles that are reliant upon internal combustion engines (ICEs), and legislators and regulators alike are concerned that pedestrians could be injured by a vehicle they can’t hear coming. The proposed standard would require hybrid and electric cars, trucks, vans, buses, and motorcycles to produce a noise that is both detectable by pedestrians from a safe distance and recognizable in a range of ambient environments. The noise must be loud enough for a pedestrian to detect from a distance of two meters, and the noise should increase at the same rate as the vehicle’s speed increases to mimic the internal combustion engine sounds to which pedestrians are accustomed. In fact, in some noise environments, the new sound standards would render electric cards and hybrids louder than their internal combustion engine counterparts.