The US is making quiet cars noisy, EV and hybrids forced to add fake sound


    The National Highway Traffic Safety Administration (NHTSA) is a division of the US Department of Transportation and have just announced a new standard that will make ‘Quiet Cars’ louder under the guise of safety.

    The new federal safety standard will help pedestrians who are blind, have low vision, and other pedestrians detect the presence, direction and location of these vehicles when they are traveling at low speeds, which they say will help prevent about 2,400 pedestrian injuries each year.

    America at a federal level will now set a  minimum sound requirements for hybrid and electric vehicles. This new standard requires hybrid and electric passenger cars, light trucks and vans (LTVs), and low speed vehicles (LSVs) to produce sounds while the vehicle is in forward motion up to 30 km/h, and reversing, meeting the requirements of this standard.

    Manufacturers have until Sept. 1, 2019, to equip all new hybrid and electric vehicles with sounds that meet the new federal safety standard. Half of new hybrid and electric vehicles must be in compliance one year before the final deadline.

    So what is that standard of noise they have to emit ? This is where things are a little in-precise, but we know our readers love the technical detail, so you can read that below. You’d think the safety concerns would be best met if this artificial sound is consistent, so a blind person for example, would easily tell that’s a vehicle, compared to any other environmental noise.

    In this final rule, the agency is reducing the number of one-third octave bands for which there are minimum requirements. The NPRM proposed that vehicles would have to emit sound meeting minimum requirements in eight one-third octave bands. To comply with this final rule, hybrid and electric vehicles will instead have to meet a requirement specifying either two or four one-third octave bands.

    Vehicles complying with the four-band requirement must meet minimum sound pressure levels in any four non-adjacent one-third octave bands between 315 Hz and 5000 Hz, including the one-third octave bands between 630 Hz and 1600 Hz (these bands were excluded in the NPRM).

    Vehicles complying with the two-band requirement must meet minimum sound pressure levels in two non adjacent one-third octave bands between 315 Hz and 3150 Hz. For the two-band requirement, one band must be below 1000 Hz and the second band must be at or above 1000 Hz, and the two bands used to meet the two-band requirement also must meet a minimum band sum requirement.

    Given where we are with the race to autonomous vehicles, I look forward to this rule being overturned if a manufacturer can prove their vehicle won’t run into people. Make no mistake about it, we’re on a trajectory in the next 10 years to reach a point where cars simply can’t have accidents and certainly can’t run into humans. When vehicles actually have a full 360 picture of the ever changing environment around them, reacting to potential incidents will quickly become second nature and automatically implementing this without human intervention is a requirement for the levels 4/5 of autonomy.

    One of the side benefits of EVs particularly is the reduction of noise and over the coming decades where our transportation switches to electric vehicles, the noise pollution found in our streets and our cities, generated by thousands of vehicles will essentially be removed. It’d be an absolute shame if this artificial noise requirement was enforced in the longer term.


    Jason Cartwright
    Jason Cartwright
    Creator of techAU, Jason has spent the dozen+ years covering technology in Australia and around the world. Bringing a background in multimedia and passion for technology to the job, Cartwright delivers detailed product reviews, event coverage and industry news on a daily basis. Disclaimer: Tesla Shareholder from 20/01/2021

    Leave a Reply


    Latest posts


    Related articles