


Several automakers have developed electric warning sound devices, and since December 2011 advanced technology cars available in the market with manually activated electric warning sounds include the Nissan Leaf, Chevrolet Volt, Honda FCX Clarity, Nissan Fuga Hybrid/Infiniti M35, Hyundai Sonata Hybrid, and the Toyota Prius (Japan only). The vehicle must make a continuous noise level of at least 56 dBA (within 2 meters) if the car is going 20 km/h (12 mph) or slower, and a maximum of 75 dBA. Manufacturers must install an AVAS system in four-wheeled electric and hybrid electric vehicles that are approved from July 1, 2019, and to all new quiet electric and hybrid vehicles registered from July 2021. In April 2014, the European Parliament approved legislation that requires the mandatory use of acoustic vehicle alerting systems ( AVAS). National Highway Traffic Safety Administration issued its final ruling in February 2018, and requires the device to emit warning sounds when travelling at speeds less than 18.6 mph (30 km/h) with compliance by September 2020, but 50% of "quiet" vehicles must have the warning sounds by September 2019. Japan issued guidelines for such warning devices in January 2010 and the U.S. Warning sounds may be driver triggered (as in a horn but less urgent) or automatic at low speeds in type, they vary from clearly artificial (beeps, chimes) to those that mimic engine sounds and those of tires moving over gravel. Warning sound devices were deemed necessary by some government regulators because vehicles operating in all-electric mode produce less noise than traditional combustion engine vehicles and can make it more difficult for pedestrians and cyclists (especially the blind or short-sighted) to be aware of their presence.

The 2011 Nissan Leaf was the first electric car equipped with Nissan's Vehicle Sound for Pedestrians.Įlectric vehicle warning sounds are sounds designed to alert pedestrians to the presence of electric drive vehicles such as hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), and battery electric vehicles (BEVs) travelling at low speeds.
