The IAM is calling for the government to pilot an 80 mph speed limit on a controlled and managed motorway to assess its practicality and safety, and road users’ reaction to it.

In September the government announced that the motorway speed limit could be raised to 80mph.

On uncongested motorways more than half of car drivers exceed the 70mph speed limit, and around a fifth exceed 80 mph; it is rare for the police to prosecute drivers travelling between 70 and 80mph.

Road safety groups have raised a concern that legalising today’s tolerated, yet unofficial, 80 mph speed limit would simply create an unofficial 90 mph limit. If this happened average traffic speeds would increase, as would accidents and their severity more people could be killed and seriously injured.

The IAM highlights the need for a full risk assessment of an increase in the speed limit, and believes strict enforcement is required to ensure greater compliance with the limit. For example driving at 82mph should risk a speeding ticket.

The IAM wants to see 80mph trialled initially on “Controlled Motorways” and “Managed Motorways” where variable speed limit technology is used. These have already been implemented successfully on the M25 orbital motorway in Surrey and the M42 in the West Midlands.

IAM CEO Simon Best said: “A fifth of motorway-users already travel at this increased speed, and more than half exceed 70mph when they can, suggesting that a properly controlled 80mph limit may not show huge increases in carbon or road casualties. A detailed trial is needed to assess these risks though, and if they are shown to increase significantly, of course a better-enforced 70 limit may be a more appropriate system.
“Raising the motorway speed limit has been debated for many years, and the evidence is that the motoring public are ready for it. The transport secretary should now publish a consultation with firm proposals.”