§ Mr. Don Foster
To ask the Secretary of State for Transport what research has been conducted(a) for and (b) by his Department into the impact of variable speed limits; what plans he has in relation to variable speed limits; and if he will make a statement. 
§ Mr. Jamieson
The Transport Research Laboratory (TRL) monitored trials on the effectiveness of variable speed limits outside schools. Variable Message Signs were installed outside schools that reduced the speed limit typically one hour around school arrival and leaving times. The result showed very little reduction in vehicle speeds and the report concluded that as a speed reducing feature they were ineffective.
The Highways Agency is also currently trialling variable speed limits on sections of the M25. Independent monitoring and assessment of the scheme is being undertaken by TRL and the results so far have been encouraging. The area over which the variable speed 111W limits operate has recently been extended. The extension is being closely monitored and results are expected next year.