A new study has shown that children are unable to judge the speed of cars travelling at faster than 20mph and are therefore in greater danger of being knocked down by cars travelling at greater speeds.

The study, from academics at the Royal Holloway College in London, shows that children's perceptual limitations put them at a greater risk of stepping in front of cars which are travelling at speeds faster than 20mph and that at greater speeds they may even be unable to detect approaching cars.

The most recent figures from the Department for Transport showed that 1,655 pedestrians aged 15 or under were killed or seriously injured in 2009 and one of the authors of the report said the research was evidence of the need to bring the speed limit down to 20mph in residential areas.

Professor John Wann, said: "Travelling one mile through a residential area at 20mph vs 30mph will only add 60 seconds to journey time. We encourage drivers to take a minute and save a child's life."

Some cities, including Portsmouth and Hull have introduced a 20mph limit in residential area, though the government says that the decision is one for the local council rather than central government.

http://www.telegraph.co.uk/motoring/news/8391189/Children-cannot-detect-cars-travelling-faster-than-20mph.html