A 2019 proposal suggested vehicles could offer a wide variety of pedestrian warning noises
The NHTSA ruled that the noise should be standardized for each car model
This is to help blind and visually impaired pedestrians be aware of a vehicle in their proximity
Since electric and plug-in hybrid vehicles are almost totally silent when driving at low speeds, they are required to emit a distinctive noise any time they are moving at less than 20 mph (32 km/h) to warn nearby pedestrians.
A proposal that had been made to the NHTSA back in 2019 wanted to let drivers choose the noise their vehicle makes in these situations from a variety of different sounds, many of them related to animals.
This proposal has just been turned down by the regulating body after inquiries on the subject have pointed out flaws in this approach.
Indeed, making the warning noise sound like an animal or an object that is not expected to be on the road could startle and confuse pedestrians, who could fail to notice a vehicle that is coming at them.
This is even more true for visually impaired people, who would have a hard time identifying and locating an approaching vehicle that makes an unexpected noise.
The new law specifically targets natural and animal sounds because they are deemed to have the most confusing effect on vulnerable road users, who could for example hear a bee buzzing around and then be surprised when it turns out they are being followed by a car that sounds like an insect.
This doesn’t mean that automakers will all be forced to use the same noise, however. Indeed, the NHTSA only rules that the chosen noise needs to be consistent among vehicles of the year, model, body style, and trim level.
This means that automakers could have a specific sound for each of their models and this sound could change every year. This also means that affordable vehicles could have a basic sound and more luxurious trim levels could make use of a more elaborate warning signal.
This decision might disappoint some EV drivers, but many associations for people who are blind or visually impaired have given their support to this outcome.