A new report from the International Transport Forum has called for 20mph speed limits as standard in built-up areas. The study examined road safety performance in ten countries after they changed speed limits or introduced automatic speed cameras and in all cases found a strong relationship between average speed and the number of crashes.

Part of the Organisation for Economic Co-operation and Development (OECD), the International Transport Forum is an intergovernmental organisation that acts as a think tank for transport policy.

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It looked at changes in speed limits in six countries and the introduction of automated speed enforcement in four more to gauge the impact on the number of collisions.

The report states that an increase in mean speed was accompanied by a higher number of crashes and casualties, while a decrease was associated with fewer crashes and casualties. In no case did an increase in mean speed coincide with fewer crashes or casualties.

The International Transport Forum therefore makes a number of recommendations.

Reduce the speed on roads as well as speed differences between vehicles

Set speed limits based on the Safe System principles, i.e. at a level that humans can survive without dramatic consequences in case of a crash

Introduce compensation measures where speed limits are increased; for instance, stricter enforcement or a safety upgrade of the road infrastructure

Use automatic speed control to effectively reduce speed

Working towards a Safe System, the authors proposed as reasonable speed limits:

30 km/h in built-up and residential urban areas where motorised vehicles and vulnerable road users share the same space

50 km/h in other urban areas with intersections and high risk of side collisions

70 km/h on rural roads without a median barrier and a risk of head-on collisions

The report also notes that lower driving speeds generally improve citizens’ quality of life, especially in urban areas.

Rod King MBE, founder and director of the 20’s Plenty for Us campaign commented:

“This is yet another report coming to the firm conclusion that 20 is plenty where people live, work, play, shop and learn.

“Other countries have adopted a near universal 30km/h limit for urban and residential streets. Over 25% of the UK live in authorities who have also set 20mph as the right urban limit. The Scottish assembly is considering a bill to make 20mph the limit (with exceptions) for built up roads. It’s time to end the postcode lottery on pedestrian/cycling safety and general well-being in our residential and urban places by setting a 20mph default limit for built-up roads across the UK.”

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