IAM calls for 80mph speed limit trial

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The Institute of Advanced Motorists (IAM) has called for an 80mph trial in preparation for the new speed limit potentially taking hold of UK motorways.

The move is proposed too address concerns about safety and the possibility of a de facto 90mph limit being established nationwide.

Although the 80mph speed limit is still in consultation, it's widely assumed that it will be written into law in 2012 – particularly as it has the vocal backing of Transport Secretary Philip Hammond.

But road safety groups reacted with vitriol when the 80mph consultation was announced, with Brake suggesting it would "legitimise law breakers".

The IAM has recognised that an "unofficial 90mph limit" could be created when the 80mph limit is established, in the same way that today's "law breakers" adhere to a pragmatic limit of 80mph.

The way to see if that actually will become the case, says the IAM, is to trial 80mph on "controlled and managed motorways" with average speed camera checks in position.

Tight law enforcement during the trial should see "for example, driving at 82mph [risking] a speeding ticket," says the IAM.

Simon Best, CEO of the IAM, said: "A fifth of motorway users already travel at this increased speed, and more than half exceed 72mph 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 70mph limit may be a more appropriate system."

The assumption that a motorway driver is currently 'safe' from prosecution at speeds up to 80mph is a reasonable one: a speed enforcement policy document issued by the Association of Chief Police Officers confirms that, normally, ten percent plus 2mph over the speed limit is the margin. That, of course, is currently 79mph.