Quiet electric cars are good for the environment but not necessarily safe. You could hit a pedestrian with an electric car and they will never know you were coming. This may not happen often, but it is a danger.
Electric cars need to make some kind of noise to let others know of their presence. Which is why a US road safety body says that the owners of electric cars should be able to choose the ‘engine’ sound for their quiet electric cars and that silent cars must generate noise when traveling at less than 19 mph.
It is possible that these cars could have minimal noises from the factory in the near future. Manufacturers were given a deadline for the noise requirement of 1 September 2019. Now, it has been extended to 2020.
National Highway Traffic Safety Administration (NHTSA) is also looking into the matter and asking the public of the possible sounds a car should make and how loud they should be. Some car makers have stepped up to make some changes. Porsche offers a ~500 USD upgrade to make the engine sound like a petrol engine, while Mitsubishi and Mercedes already have options for its electric car to make some engine sounds.