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Roads: Accidents

Volume 487: debated on Monday 9 February 2009

To ask the Secretary of State for Transport what research his Department (a) has undertaken, (b) plans to undertake and (c) has evaluated on the number of (i) minor, (ii) serious and (iii) fatal road accidents where speed was a contributory factor which drew on (A) UK and (B) international research; and if he will make a statement. (253011)

Since 2005 a report on the contributory factors, including speed, reported by police officers who attend personal injury collisions has been published as part of “Road Casualties Great Britain”. The DFT-funded “On The Spot (OTS)” study involves additional non-police investigation of road collisions to explore the characteristics of personal injury collisions in depth. The OTS study is currently examining the characteristics of crashes that involve excessive or inappropriate speed.

In addition, there is a wide range of research on the link between speed and casualties which may be found on the Department’s website at:

For example, the Transport Research Laboratory (TRL) published a review of non-UK studies in 1994 which established a link between vehicle speed and the risk of a collision. This indicated that, in broad terms, a 1 mph reduction in average speed can reduce accident risk by around 5 per cent. In 2000 TRL published a report investigating whether this general rule could be applied to different types of UK roads and to further understand the relationship between vehicle speed and accident frequency. The report concluded that the percentage reduction in accident frequency for a 1 mph reduction in average speed is between 2 per cent. and 7 per cent. depending on vehicle speeds and the nature and layout of the road.