A charity has warned electric and hybrid vehicles that are virtually silent pose a threat to the safety of blind and partially sighted people.
According to the Guide Dogs charity, blind people could be at higher risk when they cross roads, especially when there are no visual or audible indicators to control pedestrian crossing.
The Transport Research Laboratory will be releasing a report on accidents between pedestrians and quiet vehicles soon.
Carol Thomas, Guide Dogs' access and inclusion manager, said: "We recognise the environmental benefits of electric and hybrid vehicles.
"However they are virtually silent, and blind and partially sighted people rely on vehicle sound to assist with their mobility and orientation.
"This is particularly important when crossing roads, especially when there are no controlled pedestrian crossings with audible and tactile indicators. The sound of oncoming traffic, or absence of this sound, is used to assess when it is safe to cross the road.
"It is also helpful to blind or partially sighted people to know when vehicles are waiting at traffic lights. If a hybrid vehicle is stationary at a pedestrian crossing, it may not be heard but may be about to move."
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