HC Deb 05 March 1990 vol 168 cc512-3W
Mr. Batiste

To ask the Secretary of State for Transport (1) whether he has undertaken any studies in the United Kingdom on the implementation of transitional lighting and the effect of it on accident rates at night;

(2) what research he is undertaking to assess the safety implications for a transitional lighting system to allow drivers to adjust from lit motorways to darkness.

Mr. Atkins

Studies in many countries, including the United Kingdom, have shown that the transition from bright sunlight conditions to those lighting conditions in a road tunnel is a problem because of the reduction in road surface luminance of about 50,000 candelas per square metre. On average, this transition lasts several seconds. Transitional lighting is therefore justified and provided.

The equivalent transition from lit to unlit motorway at night represents a reduction in luminance of just 2 candelas per square metre and is completed in about one second. The potential in these circumstances for any effect on accident rates is negligible. No research is therefore being undertaken into this aspect.

If my hon. Friend has specific evidence that he feels merits looking into, I will consider it.

Mr. Batiste

To ask the Secretary of State for Transport what is the standard intensity of lighting on lit motorways, rural and urban roads.

Mr. Atkins

The standard average luminance of lighting on lit trunk roads in England is as follows:

Candelas per square metre
Motorways 2.0
Dual carriageways and high speed roads 1.5
Other trunk roads 1.0

These standards are in accordance with the recommendations of the appropriate national and international standards bodies.

The standard of lighting installed on other roads is a matter for the highway authority concerned.

Mr. Batiste

To ask the Secretary of State for Transport what technology is available to light sections of roads and motorways at different levels to allow people to adjust to lighting changes.

Mr. Atkins

Lighting technology is available, or can be readily adapted, to provide a range of road lighting levels. This can be achieved by altering the type of lamp, the electrical control system, the column height and the column spacing, or by a combination of these means.

Forward to