§ Mr. Stringer
To ask the Secretary of State for Transport what estimate he has made of the effect of providing lighting on the whole of the motorway system on the number of recorded accidents. 
§ Mr. Jamieson
No estimate has been made of the effect of lighting the whole of the motorway network. Research has shown that where motorway lighting is provided the number of reported accidents can be reduced by about 8 per cent. and can result in a reduction of night-time personal injury accidents by as much as 30 per cent.
Lighting is generally only provided where there are particular problems and where the economic assessments show the cost of installation and operation of lighting is exceeded by the benefits of reduced nighttime accidents. At present, approximately 30 per cent. of motorways are lit.