Artificial EV sounds will add to noise pollution

ev-noise-debate4morgan-blog-rollI have lived in small towns of 2,000 people and large state capitals, and it surprises me how much noise a city creates compared to small rural towns. Sirens go off in the middle of the night, loud music blasts from the neighbor’s house, and there’s almost always the hum of traffic in the distance. After months of adjusting to the city, I hardly realize the noise anymore.

But just because I don’t notice it, doesn’t mean the noise isn’t there affecting me.

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Noise pollution adversely affects the overall health of millions of people, according to the U.S. Environmental Protection Agency. Noise pollution is defined as any “unwanted or disturbing sound” that interrupts day-to-day activities such as sleeping, conversation, or concentration.

The issue of noise pollution does not receive very much attention, because people can’t see, smell, or taste it—so other health issues like air and water contamination take the foreground.

However, with the recent development of electric vehicles (which are quieter than most other vehicles on the road) vehicular noise got some attention.

Prompted by the EV rise, Congress passed the Pedestrian Safety Enhancement Act of 2010, which requires electric and hybrid vehicles to establish a sound, in order to help alert blind and other pedestrians who are nearby.

Here are the main points of the Act:

  • The driver or pedestrian shall not be required to activate the sound;
  • Pedestrians should be able to reasonably detect a nearby electric or hybrid vehicle in critical operating scenarios including, but not limited to, constant speed, accelerating, or decelerating;
  • The Secretary of Transportation shall allow manufacturers to provide each vehicle with one or more sounds that comply with the motor vehicle safety standard at the time of manufacture;


  • Manufacturers will be required to provide, within reasonable manufacturing tolerances, the same sound or set of sounds for all vehicles of the same make and model;
  • Manufacturers will be prohibited from providing any mechanism for anyone other than the manufacturer or the dealer to disable, alter, replace, or modify the sound or set of sounds;
  • The manufacturer or dealer may alter, replace, or modify the sound or set of sounds in order to remedy a defect or non-compliance with the motor vehicle safety standard;
  • The Secretary of Transportation shall promulgate the law no later than 36 months after the law was enacted. The rulemaking shall begin no later than 18 months after the passing of the law, and when rulemaking the Secretary shall:
    • Determine the minimum level of noise required to alert pedestrians and blind;
    • Consider the overall community noise impact;
  • A phase-in is required for the vehicles. However, no later than 48 months after the enacted of this Act, the Secretary of Transportation must report to Congress whether or not the safety Act needs to be applied to conventional motor vehicles;
  • If the Secretary of Transportation determines that a safety need does exist, then the law will be applied to all standard conventional motor vehicles.
  • “Motor vehicle” is defined by the law as, “a vehicle driven or drawn by mechanical power and manufactured primarily for use on public streets, roads, and highways, but does not include a vehicle operated only on a rail line.”

A mis-focused law?
So, after considering this new law, I really wonder what truly has a larger impact: less noise on the road, or adding to noise pollution?

An online discussion held on a Priuschat Forum recently indicates many people are opposed to the law.

Let’s see what some of the commentary was:

    • “The law is mis-focused. All modern cars are incredibly quiet at low speed; mostly what you hear is tire noise. It’s not really an EV or PHEV issue. Focusing on EVs and PHEVs takes attention away from where it belongs, which is getting people’s attention back onto whatever it is that they are doing, whether it be driving or walking.”
    • “Increased pedestrian safety is a wonderful idea. But that’s not what this Act is about – it’s an attack on hybrids. It doesn’t apply to all vehicles based on noise levels, nor does it bear any relation to statistical evidence of a problem.”
    • “The UK Leaf models were held back from initial release whilst Nissan DISABLED the noise maker as it conflicted with a law about artificial noise from vehicles at night. So our UK EV’s are nice and quiet. Oh and I drive a Prius as a taxi here in the UK and one of my corporate customers is a blind [colleague]. I have spoken to the students at length about the noise of my car and they can hear it at low speeds – especially now that they are aware of what to look out for (pardon the pun!). In fact they enjoy being a passenger in my Prius because it is so quiet.”
    • “I don’t see any harm to alert a blind person or pedestrian in certain situations that call for it…I don’t see this as a threat to EV’s but a push to reach a common sense compromise that benefits all parties. And if it’s carried out in common sense, I’m for it.”


    • “The fact is, very few people are blind and in need of a noise-maker. The vast majority of people are fully capable of seeing a vehicle that poses a threat to them navigating a roadway. So the simple and polite solution for everyone involved– assuming there’s even a need for such a law– is that we require a short-range transmitter in quiet vehicles that activates a small, relatively quiet alert device in a blind person’s cane, or wrist watch, or pendant etc. that gets louder the closer the vehicle is to them.”
    • “So all golf carts and Segways should have these noise makers fitted too then. I’m mean hey, driving a golf cart could be dangerous – all those people on golf courses not expecting an EV to sneak up on them and run them over. What about an alternative to the noisemaker? A speed sensitive horn? Below 10 mph it emits a softer alert so as not to induce a heart attack on the pedestrian and above 10 mph it emits the usual sound? I still think this noise maker nonsense is all about trying to restrict EV sales.”

No one in the discussion expressed a concern for noise pollution, but many people questioned the actual necessity of the law.

Given all of the health issues that have been noticed — though not extensively studied…yet — plus my own experience of adapting to a louder environment when I moved to a city, I can’t help but wonder just how much of an impact noise is having on us.

Again, there is a general lack of public knowledge regarding noise pollution, and many people are not even consciously aware of the noise that exists in their environment, or the impact that it can have on their health.

Noise pollution
Given all of the health issues that have been noticed — though not extensively studied…yet — plus my own experience of adapting to a louder environment when I moved to a city, I can’t help but wonder just how much of an impact noise is having on us.

According to the article published in 2003 by Oxford Journals, “Noise pollution: non-auditory effects on health,” noise interferes with task performance, modifies social behavior, and causes annoyance.

Researchers Stephen Stansfeld and Mark Matheson outlined other associations between health and noise that they found in their research:

  • Occupational and environmental noise exposure à linked to hypertension
  • Aircraft and road traffic noise exposure à linked with psychological symptoms
  • Industrial and community noise à linked to raising catecholamine secretion
  • In children, chronic aircraft noise exposure à associated with raising blood pressure, and weakening reading comprehension and long-term memory

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Furthermore, according to the Centers for Disease Control and Prevention, noise has effects on health including hearing-loss, sleep disturbance, cardiovascular and physiologic problems, performance reduction, annoyance responses, and can contribute to adverse social behavior.

With the consideration of noise pollution and its health effects, perhaps the studies will determine that a noise requirement will have a greater negative impact than a positive one.

Or, maybe all of the motor vehicles on the road will be required to adopt noisemakers.

Beep. Beep. Beep. Beep. Beep.

I think it would be better if things were quieter…

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