Electric cars – learning the new sound of danger
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According to the Society of Motor Manufacturers and Traders (SMMT), more electric cars were registered in 2021 than in the previous five years combined. Noise and air pollution have been a driving factor in the rising number of electric vehicles (EVs) and hybrid electric vehicles (HEVs) on the roads, and the government is planning on banning the sale of new cars and vans powered entirely by petrol or diesel by 2030.
However, because electric vehicles are dramatically quieter than ones powered by petrol and diesel, it has raised the question of whether these low noise vehicles increase the risk of accidents involving cyclists and pedestrians, with a particular emphasis on visually impaired pedestrians.
Do electric cars cause more accidents?
Several studies have been carried out to determine whether there is a higher risk of accidents involving electric or hybrid vehicles compared to vehicles with a traditional engine. One such study (The detectability of conventional, hybrid and electric vehicle sounds by sighted, visually impaired and blind pedestrians, Altinsoy, E., 2013) focused on the detectability of electric vehicles. The study found that pedestrians with or without a visual impairment were able to detect the sound of a vehicle with a traditional engine from about 36 metres distant, electric vehicles weren’t heard until they were at most 14 metres away.
The Department for Transport commissioned the Transport Research Laboratory to carry out investigations into accident statistics involving pedestrians and EVs/HEVs, and pedestrians and internal combustion engine (ICE) vehicles. While currently the relative number of EVs/HEVs involved in any accident is still smaller than traditional vehicles, proportionately more of the EV/HEVs accidents involved pedestrians. The investigation also found that there is a higher risk of accidents involving EVs/HEVs when driving at low speed in urban areas, but this risk was still relatively small. The important point to bear in mind here is that despite the rise in their sales, it was estimated that only 2% of cars on UK roads were electric or hybrid as of December 2021.
Making electric vehicles safer
In 2019, the European Commission said that when EVs/HEVs are driving at 12mph or less, they must be fitted with an acoustic vehicle alerting system (AVAS) to alert pedestrians when a vehicle is close. On 1 July 2019, it became mandatory in the EU for any new electric, hybrid, plug-in hybrid, and fuel cell vehicle to be fitted with an AVAS. From 21 July 2021 it also became mandatory for all existing electric vehicles to have an AVAS, not just new models. The noise must change as the car gets slower or faster to ensure that pedestrians can identify what the car is doing based on the sound. The sound must be like that from a fuel powered vehicle, but the manufacturers can decide what specific form of noise their AVAS will emit. Manufacturers have seized this as an opportunity to craft an identity for their cars and the artificial sound can vary from a low hum to a musical tone. Where the noise of a vehicle is currently universally recognisable, this does present a danger that people may not understand that what they’re hearing is a warning.
Although the use of AVAS is mandatory for all UK-registered vehicles, they can be deactivated by the driver using a pause switch. This has caused for people, in particular people within the blind and visually impaired community, to call for a change in laws due to the danger these silent vehicles can present. In response the Department of Transport has said that a regulation preventing manufacturers from installing the pause switch will be brought in on 1 September 2023. Additionally, the AVAS will only be activated when the car is travelling at 12mph or less. Some have asked for this to be increased as they are not convinced an electric car travelling at 13mph will emit enough sound to alert a pedestrian or cyclist of their presence. All these safety issues need to be addressed to ensure the safety of cyclists and pedestrians as the sale of these vehicles is due to rise dramatically.