Tag Archive: electric vehicles

Will electric vehicles reduce city traffic noise?

Photo credit: G.M. Briggs

By Daniel Fink, MD, Chair, The Quiet Coalition

Some people put great hope in technology to solve problems of modern living. So it is with those who think that electric vehicles, whether trucks or other vehicles, will do the trick. I’m in favor of electric and hybrid vehicles for their beneficial effects in reducing the use of petroleum products and reducing gaseous and particulate emissions. Anything reducing diesel use will have a dramatic benefit in reducing particulate matter. So news that Ryder, “one of the nation’s largest medium-duty truck fleet management companies, will buy trucks from Chanje [an electric truck manufacturer], then lease and service them through its extensive network,” is welcome. But will electric vehicles reduce city traffic noise? I think not.

First, it will take years if not decades for electric vehicles to become more common. Second, and perhaps more importantly, power train noise is a small component of road traffic noise in most situations. I suppose a diesel hybrid vehicle idling on electric will be quieter than the same vehicle powered solely by a diesel engine, but adequate insulation of the engine compartment and an effective muffler system would do the trick just as well.

And of course, electric vehicles won’t do anything about horns, horn-based alerts, or sirens.

The technologies to reduce or control noise have been known for decades. Acoustics pioneer Leo Beranek published his landmark book, “Noise Reduction,” in 1960 and the successor, “Noise and Vibration Control,” in 1971. As noise pioneer Arline Bronzaft, PhD, has written, what is lacking is not the way but the political will.

Road traffic noise is a health and public health hazard, causing non-auditory health impacts like hypertension, diabetes, cardiovascular disease, and death. The European literature makes this very clear. There is no reason to think that Americans, largely of European descent and those from elsewhere, have different physiological responses to noise exposure.

If enough people loudly demand that their elected officials pass and enforce laws to make vehicles and streets quieter, our cities and their streets will become quieter. Electric vehicles may or may not play a small role in this, but they are largely irrelevant.

Dr. Daniel Fink is a leading noise activist based in the Los Angeles area. He serves on the board of the American Tinnitus Association, is the interim chair of Quiet Communities’s Health Advisory Council, and is the founding chair of The Quiet Coalition, an organization of science, health, and legal professionals concerned about the impacts of noise on health, environment, learning, productivity, and quality of life in America.

Will electric vehicles contribute significantly to a quieter world?

Photo credit: cytech licensed under CC BY 2.0

Jeanine Botta, of Silence the Horns, expresses some doubts in her post, “Marketing quiet while adding to noise pollution.” Botta writes about a recent post on Huffington Post that discusses the health effects of traffic noise.  She notes that the piece, which “tells us that ‘EVs are bringing the quiet’ and concludes that ‘…you could say we’re about to enter a golden age of silence,'” was promoted by Nissan, with “Brought to you by ELECTRIFY THE WORLD – A NISSAN INTELLIGENT MOBILITY INITIATIVE” appearing next to the Huffington Post banner.  “Welcome to the world of advertorial marketing,” she says. 

What follows is Botta’s thoughtful analysis of why electric cars may not be “bringing the quiet” any time soon.  More importantly, if concern about vehicle noise is more than a marketing ploy, manufacturers should look at Botta’s suggestions on how they can “substantially reduce vehicle noise pollution” right now in both electric vehicles and in internal combustion engine cars by simply phasing out audible alarms and signals.

Click the first link above to read Botta’s entire piece.  It is well worth your time.

How can big cities deal with noise pollution?

Based on a recent increase in news items about noise in cities, the issues of urban soundscapes and noise pollution seem to be getting more attention. Included in this recent spate is an article by Robert Bright, The Huffington Post, who writes about smart, sound solutions to urban noise. Bright begins his article by noting that most people tend to think of noise pollution as “a cause of irritation and sometimes anger,” but fail to regard it as “doing us any physical harm.” But Bright shows that noise is more than a mere nuisance, as he discusses a recent study by Mimi Hearing Technologies which shows that people who live in noisy cities are more likely to suffer hearing loss, a not insignificant health problem. In fact, the World Health Organization estimates that the cost of hearing loss is $750 billion globally, which  includes medical bills, lost earnings, and related problems people suffer when they lose their hearing (but does not consider other effects of noise, like stress, fatigue, and poor sleep quality).

So, armed with the knowledge that urban noise pollution is a serious health threat, what can we do? Bright thinks that electric vehicles (EVs) will help to quiet the din, as they make very little noise. He also suggests that the ubiquity of smartphones coupled with free, downloadable sound meter apps will allow cities to compile noise maps that will allow users to avoid noisy areas and help city governments target noisier areas for sound mitigation. Other possibilities exist too, like the development of “radical new materials” that “could provide hitherto unimaginable forms of sound proofing in the future,” to ridiculous street furniture designs like the “Comfort-Shell,” “a giant helmet-shaped object positioned above the head which drastically reduces noise.”

The good news is that whatever method or products are used to address noise in the future, it is clear that noise can no longer be ignored. As Bright concludes, there is a marked “shift in approach to noise pollution” that “combined with citizen activism, increased EV usage and a more mindful attitude to how we are affected by the sounds around us…is putting city life on the cusp of a ‘quiet revolution.’”

 

Electric cars must make noise after September 2019:

car-bmw

“Quiet Car” rule will require all electric vehicles to make noise, so pedestrians can better hear and avoid them.  CNET.com reports on the long-awaited National Highway Traffic Safety Administration rule requiring auto manufacturers to add waterproof, temperature resistant sound generators to hybrid and electric vehicles sold after September 1, 2019.  Referred to as vehicle warning sounds, the sound will be automatically activated when a car travels at speeds below 18.6 miles per hour.

Electric and hybrid cars are noticeably quieter than cars powered by an internal combustion engine.  This fact drew the attention of advocates for the blind and visually impaired a decade ago, ultimately leading to the passage of the Pedestrian Safety Enhancement Act (PSEA) of 2010.  The PSEA is intended to reduce the risk of harm to blind and visually impaired pedestrians, as well as cyclists, or anyone unable to hear the very quiet approach of these cars, by requiring electric and hybrid cars to emit a minimum added sound.  The issue regarding this requirement is complex and contentious, and it has generated a lot of research and extended discourse both for and against added sound.  Many electric and hybrid cars have used added sound for years; samples of some sounds can be found online.

A significant concern is that some automakers see the need to comply with the rule as an opportunity to invent branded sounds, while critics of branded sounds would prefer sounds as similar as possible to a vehicle engine, noting that discordant or unusual sounds could actually create confusion.  In addition, environmental advocates and soundscape preservationists have expressed concern about adding more noise to an overburdened soundscape.

One problem with reaching a sensible solution is that the instructional videos produced by industry tend to show cars and pedestrians interacting in open spaces, but real world experiences are more likely to occur in busy parking lots or residential streets.  Measures such as traffic calming and slow zones could result in a growing number of areas where driving below 20 miles per hour would be the norm in order to improve safety for pedestrians, cyclists, and drivers.  One thing is clear, vehicle engineers must incorporate these details into the planning of current and future warning sounds.

Asked about branded sound design, Jeanine Botta, who runs the Green Car Integrity Project blog, said that she hopes sound designers will follow the rule’s requirement that sound be recognizable as a motor vehicle in operation, and let go of branding concepts.  “Our attention is already stretched to its maximum potential.  No pedestrian – or cyclist or motorist – should have to quickly process and interpret any sound, especially one intended for safety.  If a sound is the least bit discordant, it runs the risk of being misinterpreted and ignored.”

Automotive product developers considering new and improved added quiet car sound should include industry outsiders in the research and development process.  Consultation with environmental psychologists, environmental health researchers, acoustic ecologists, and soundscape preservationists would be a step in the right direction.