Why it matters: Would you like to choose which artificial motor sound your electric vehicle makes when traveling at low speeds? It looks like it will happen, following a proposal from the National Highway Traffic Safety Administration (NHTSA).

The NHTSA finalized rules in 2018 requiring all newly manufactured EVs and hybrids to emit alert sounds at speeds under 18.6 mph to warn pedestrians. In the agency's updated proposal, drivers should be able to "select the sound they prefer from the set of sounds installed in the vehicle."

Automakers were required to have the alerts in 50 percent of their "quiet" vehicles by September 1, and the sounds must be in every quiet vehicle by September 2020.

Electric cars are much quieter than vehicles with internal combustion engines, though tire noise, wind resistance, and other factors eliminate the need for an alert sound when traveling at high speeds. When moving at low speeds in locations such as parking lots, there's the risk of unaware pedestrians walking out in front of the cars. According to the NHTSA, the low-speed alerts will help prevent 2,400 injuries annually.

The European Union will also be requiring new EVs to be fitted with noise-making devices. The Acoustic Vehicle Alert System, or AVAS, makes a noise like a standard engine when the vehicle drops below 12mph. You can hear it yourself in the clip below.

Reuters writes that the NHTSA believes adding external waterproof speakers will cost the auto industry about $40 million annually, but the benefits of reduced injuries are estimated at $250 million to $320 million annually.