Blanket 20mph limits a priority, says academic

Speed Limits

Reducing almost every 30mph speed limit in Britain to 20mph should be the top priority for local authorities if they want to improve their population’s health, according to an academic.

Danny Dorling, professor of geography at the University of Oxford and patron of RoadPeace, makes the case for lower limits in a new report by the British Academy looking at how councils can reduce health inequalities.

Dorling says 30mph limits should “in almost all cases become 20mph”.

“By grouped cause of death, the biggest killer in Britain of children between 11 and 16 years old, and, in fact, anyone between the ages of 5 and 25 is road traffic crashes,” he says.

“When vehicles are travelling at 20mph or below, most adults and children survive collisions.”

Dorling cites material from the website of campaign group 20’s Plenty to suggest that 20mph limits are actually better for drivers because they cut spacing between vehicles as braking distances contract. “Shorter gaps mean more vehicles can use the available road space, reducing standing traffic.”

Evidence from Bristol shows walking and cycling increase in 20mph limit areas, he adds. 

“We are getting very close to the point where it [20mph] now makes sense as a national limit. The tipping point may well be the decision reached in summer 2013 for all the roads in the City of London to switch to be 20mph.

“If we saw cars as being as important an influence on our poor health as we now see cigarettes we would not have such a benign view of them.

Discuss this at LTT's Time for 20mph event on the 18 Feb 2014