Motorway 60mph speed limits remain - despite no evidence that they work

Air pollution speed limits that force motorists to drive at 60mph should end, campaigners have said, after it emerged they have lasted twice as long as originally proposed

without producing evidence they work. Drivers on stretches of the M1, the M6, the M5 and the M602, have been limited to a top speed of 60mph in a bid to ascertain if driving

more slowly helps reduce emissions. But the restrictions, which were only supposed to last between 12 and 15 months, have now been running for more than two years, despite

no evidence to show they are effective. There are even questions over whether the increased congestion caused by the new speed limit may have actually increased

pollution. Motoring groups and a former roads minister are among those now calling on National Highways to come clean with the data or end the

trials. GGGHGHGHGHGH The lowering of the speed limit was introduced based on modelling that claimed it would significantly reduce the annual mean nitrous dioxide

concentrations in the affected zones. It was suggested this would help the areas around the trials near Rotherham in South Yorkshire; Witton in Birmingham; Eccles in Greater

Manchester and Oldbury in the West Midlands meet pollution limits one to two years earlier than expected. But The Telegraph understands the modelling did not take account of

particle pollution produced by braking. The policy also penalises electric vehicles which produce no exhaust emissions and newer, less polluting cars.