Photo credit: S. von Hoerst
by Jeanine Botta, MPH, Co-founder, The Quiet Coalition
In late July, residents of two San Francisco apartments began losing sleep as the sounds of horn honking from a fleet of autonomous vehicles filled the parking lot their buildings face. Waymo, a driverless ride-hailing service, had rented the parking lot for its cars to idle in when not engaged. As the parking lot filled near capacity in early morning hours, the cars’ systems perceived nearby vehicle movement as a safety hazard and emitted “false positive” horn honks.
Residents took to social media, posting videos and commiserating in chats, and one livestream drew hundreds of visitors. Within two weeks, a Waymo product developer joined the livestream’s chat to let sleep deprived residents know that a software fix had been developed. There would be more software fixes as the problem persisted, but Waymo has persisted too.
This situation is in marked contrast to U.S. automaker responses to feedback from the public – in letters, online forums, articles and social media posts – about the sleep disruption caused by a more chronic form of vehicle noise, horn-based lock confirmation with a key fob. U.S. automakers don’t join live chats to talk about how they plan to fix their noise problem. When they do respond to complaints from the public, it has been to state that car owners like the feature, and if they wanted to, they could opt for a visual confirmation or no confirmation at all. In a nod to environmental responsibility, some automakers have included a sentence in car owner manuals recommending that owners familiarize themselves with local sound ordinances.
The situation in the San Francisco parking lot was dramatic and acute, requiring a fast response. Resolution was not immediate, but the responsible party continued its effort to resolve the issue. Waymo has thought about its vehicles’ sound emissions, apparent from its position on acoustic vehicle alerting systems and focusing on reducing false positive horn honking, both mentioned in a blog post from 2016. “Our goal is to teach our cars to honk like a patient, seasoned driver,” it reads.
U.S. automakers have made liberal use of horn sounds, disregarding the Uniform Vehicle Code, and state and local sound ordinances that limit horn use to warning of imminent danger while a car is in motion. Frequently heard in parking lots by nearby residents or hotel guests, horn sounds are used by more than half of U.S and Canada car brands to signify locking and remote start.
Early generations of the Chevy Volt and Nissan Leaf used a horn sound to signify stages and status of battery charging, which is sometimes offered in residential parking lots. Early generations of the Volt used a horn sound as its acoustic vehicle alerting system.
It is easier to ignore a problem when it is chronic rather than acute. Regardless of how much has been learned about non-auditory effects of noise on health, some in positions of power still treat noise violations and those who report them as trivial, in order to justify not taking action.
Sleep research shows that the effects of noise on sleep are associated with serious health outcomes that include cardiovascular disease, diabetes, cancer and neurodegenerative disease. Research on musculoskeletal disorders shows that sleep deprivation directly impacts chronic pain, and that improving sleep results in improvement in symptoms of musculoskeletal disorders and chronic pain. Many other health and mental health conditions are exacerbated by sleep disruption and deprivation, and poor quality of sleep.
Every effort should be made to prevent unnecessary vehicle noise, whether the noise problem is acute or chronic. Rather than adding to the growing array of uses for horns as reminders and status reporters, automotive product developers should eliminate horn-based alerts from all future generations of vehicles. They should implement software fixes capable of swapping horn-based alert sounds for soft electronic tones in existing vehicles.
With the Waymo vehicles all honking in a small lot, and a humorous, technically skilled resident able to capture and broadcast an acute situation in need of a quick remedy, the stars aligned. The problem of chronic sleep disruption due to horn-based lock alert and remote start use isn’t as obvious, but still ought to be resolved.
