The Dangers Of Silent Electric Cars: A Hazard For Pedestrians

Every customer has their own reason for selecting the vehicle(s) they drive. It may be a little more specialized for work, or it's simply be a matter of budget, or maybe there's a fondness for a particular brand. Another primary factor that can play into this is environmental concerns.

Where the latter is a priority, electric vehicles are certainly an attractive option. Not only do they cut out that dreadful gas pollution -– the U.S. Department of Energy states that a colossal amount of carbon dioxide amounting to around 1.5 billion tons is emitted by cars every year – but they help with another form too: Noise pollution.

For some drivers (and those in a vehicle's vicinity), the delicate hum of an electric vehicle makes a nice quiet change. For others, it's rather unnatural, a sign of a huge, sweeping change that the motoring world is still struggling to take on board (that being EVs more broadly).

The absence of a petrol or diesel engine's characteristic cacophony, however, will become a growing problem for pedestrians as such vehicles become more common.

A silent danger

The Injury Prevention study "Headphone use and pedestrian injury and death in the United States: 2004–2011," from Richard Lichenstein et al, provides some sobering information. It's acknowledged that, over this period, 116 pedestrians were killed while wearing headphones, slightly over half of them by trains. 29% of them were tragically killed after an audible warning was given. The message is clear: the deaf, hearing impaired, blind, and vision impaired must be safeguarded against the dangers of these far quieter cars, as not sensing the approach of oncoming vehicles can be fatal.

Those varied electric cars may not be entirely silent while in motion, but compared to some of the roaring vehicles on our roads, they're as good as. In the light of this, lawmakers had a bright, lifesaving idea: Just as natural gas is artificially infused with the foul-smelling mercaptan so that potential gas leaks can be quickly discovered, so electric vehicles should have sounds and sensors intentionally added so that it's easier to hear them coming.

Across the European Union, legislation came into effect in July 2019 to address this. Uniform Provisions Concerning the Approval of Quiet Road Transport Vehicles with Regard to their Reduced Audibility may be quite a mouthful, but it boils down to this: Electric cars in the E.U. require an Acoustic Vehicle Alert System that makes, New Atlas reported, "a continuous noise of at least 56 decibels if the car's going 20 km/h (12 mph) or slower."

Slower isn't always safer

In the United States, similar regulations were also set down. A final rule from the National Highway Traffic Safety Administration from November 2016 defined what it called the Minimum Sound Requirements for Hybrid and Electric Vehicles. In a similar fashion, it notes, it "requires hybrid and electric passenger cars and LTVs with a gross vehicle weight rating (GVWR) of 4,536 kg (10,000 lbs.) or less and LSVs, to produce sounds meeting the requirements of this standard."

Both of these regulations specifically target EVs that are traveling slowly, and the National Highway Traffic Safety Administration explains why: "At higher speeds ... tire and wind noise are the primary contributors to a vehicle's noise output, so the sounds produced by hybrid and electric vehicles and ICE vehicles are similar." EVs that are moving slowly enough not to produce such ambient noises, then, are a major threat.

In October 2011, the U.S. Department of Transportation and the National Highway Traffic Safety Administration distributed the study "Incidence Rates of Pedestrian And Bicyclist Crashes by Hybrid Electric Passenger Vehicles: An Update." In a study of 16 states, researchers determined that a hybrid had a 57% greater chance of being involved in an accident with a bicycle, and was 37% more likely to experience a crash involving a pedestrian than a petrol or diesel vehicle.

As the adoption of EVs continues to increase, then, so should the measures taken to keep pedestrians safe.