Time to Raise Outdated Motorway Speed Limit
Alliance of British Drivers calls for 80mph speed limit proposal to be revived
The 22nd of December will mark the fiftieth anniversary in 1965 of the introduction of an 'experimental' national speed limit of 70mph, on all roads without any other limit. After extensions to the initial three-month trial, the limit was made permanent in 1967.
The limit was introduced as an illogical reaction to a series of multiple accidents on motorways in fog. That such accidents occurred and continue to occur is not surprising, since drivers have never been offered effective training in judging speed and distance within the unique visual environment of a motorway. A 70mph speed limit imposed in good conditions cannot prevent accidents in poor visibility. The report on the 70mph 'experiment' attempted to justify its continuation but provided no valid evidence that accidents had reduced.
Substantial improvements have been made in vehicle and highway engineering in the last half-century. Drivers are much more accustomed to motorway driving, even though training is still inadequate. Today's widespread lack of compliance with the 70mph speed limit is an indication of its irrelevance to modern conditions and is detrimental to respect for speed limits in general. Other adverse effects are tailgating, poor lane discipline, 'undertaking' and lack of driver concentration. It is also preventing the full economic benefits being achieved from the nation's investment in a high-standard motorway network.
Former Transport Secretary Philip Hammond indicated his support for raising the motorway speed limit to 80mph, but the proposal appears to have been shelved by his successors. This is presumably because of concerns that accidents might increase, but such fears are unfounded.
Since 1995, when the U.S. Government abolished the federal 55mph speed limit, most states have raised their speed limits on motorway-type roads. In virtually all cases, these changes were strongly opposed by the safety lobby, which anticipated huge increases in casualties. Analysis of accident trends, however, shows no such increases. Indeed, in some cases, the states that raised their speed limits saw a greater fall in casualties than those that did not 1
. Fears that raising the speed limit would lead to drivers increasing their speed by the same amount were also unfounded. Most drivers continued to travel at around the same speed they did before.
Many U.S. states are continuing to raise their speed limits to bring them into line with best practice in speed limit setting, known as the 85th percentile principle (setting limits at a level that 85% of drivers would not choose to exceed anyway 2
). By setting speed limits in this way, not only is a high degree of compliance achieved but the spread of speeds (variance) reduces 3
. Research shows that speed variance has a much greater bearing on accident rates than average speed 4 5
. Indeed, UK Government policy on speed limits for the last twenty years has been based on studies that have ignored speed variance, leading to a misguided policy of ever lower limits.
Most other EU countries have motorway speed limits higher than 70mph, with 130km/h (81mph) being the most common. It is time the UK's motorway limit (and that of high standard dual carriageways) was brought up to date. This would bring economic benefits, improve traffic flow, and end the needless prosecution of safe drivers.
ABD director Ian Taylor comments:
“Fifty years after it was introduced, the 70mph speed limit has long lost the respect of the majority of drivers. The Government should increase the limit to 80mph without further delay, to bring it into line with modern safety standards and most other EU countries. This should be followed with a thorough review of speed limit policy, reinstating the 85th percentile as the basis of setting local speed limits, to encourage the greatest compliance, lowest spread of speeds and minimum accident risk.”