The US federal government has revised a February 2018 ruling which requires EVs and hybrid vehicles to emit acoustic vehicle alert systems (AVAS) sounds at low speeds to alert nearby pedestrians, now saying that drivers should be given the choice of which sound they prefer from a pre-set list of available car sounds.
The US National Highway Traffic Safety Administration (NHTSA) issued a notice of proposed rule-making on Tuesday which would “allow manufacturers of hybrid and electric vehicles (HEVs) to install a number of driver-selectable pedestrian alert sounds in each HEV they manufacture”.
This is so that “drivers would be able to select the sound they prefer from the set of sounds installed in the vehicle,” the notice said.
The proposed new rule would be an amendment to the rule issued in February 2018 requiring EVs and hybrid vehicles to produce noise when travelling at low speeds.
US vehicle manufacturers have until 2020 for full compliance, while vehicles sold in the European Union have until 2021.
The ruling is based on the fact that electric cars, specifically, are quieter than traditional internal combustion vehicles, with noise generated only by wind resistance and tire noises.
“We all depend on our senses to alert us to possible danger,” US Transportation Secretary Anthony Foxx said in a 2016 statement.
“With more, quieter hybrid and electrical cars on the road, the ability for all pedestrians to hear as well as see the cars becomes an important factor of reducing the risk of possible crashes and improving safety.”
The NHTSA is also seeking comment from the public on whether vehicle manufacturers should limit the number of sounds installed from which a driver may choose.
“The National Highway Traffic Safety Administration is requesting public comment on amending the new Quiet Vehicle safety standard FMVSS No. 141, Minimum Sound Requirements for Hybrid and Electric Vehicles, to allow multiple driver-selectable sounds so long as they meet the existing performance requirements,” an agency spokesperson said in a statement.
“NHTSA is considering whether to allow hybrid and electric vehicles to be equipped with a suite of pedestrian alert sounds from which a driver may select a preference.”
Some automotive manufacturers, such as Mercedes-Benz and Volkswagen, have already chosen their preferred sound.
“The electric vehicle sound is its identity,” Frank Welsch, responsible for technical development at Volkswagen, told Reuters in March.
“It cannot be too intrusive or annoying. It has to be futuristic and it cannot sound like anything we had in the past. We cannot simply add the sound of a combustion engine.
“Performance models need to have a more assertive sound, with more bass. It cannot be a high-pitched din, like a sewing machine. It has to be futuristic.”
Mercedes-Benz has specifically chosen for its EQC model an artificial humming noise which will be loud enough to warn pedestrians that the vehicle is approaching.
“We want the car to be as quiet as possible from the interior, but there are rules for sound decibel levels for the exterior,” said Jochen Hermann, head of electric drive development at Mercedes-Benz. “We picked an acoustic signal for the EQC about a year ago and made a choice between three different sounds,” he added.
Meanwhile, Mercedes-AMG is working with American rock band Linkin Park to find a sound for its electric cars, while the BMW Group is working on the sound for a new electric Mini. “Sound is definitely something that will shape the car’s identity,” said Esther Bahne, Vice President Strategy and Innovation at BMW’s Mini.
Australia is looking to follow the lead demonstrated by the US and Europe; the Australian federal department of Transport and Regional Development is currently developing a “Regulation Impact Statement” to determine what shape Australian AVAS laws may take.
However whether or not Australian drivers will also get to choose their own sounds is not yet known.