Abstract
This paper reports the requirements of the Nordic Road Association for lighting in road traffic tunnels. The objective of lighting is so that traffic can enter, pass through and leave the tunnel in safety. Lighting must give the carriageway an adequate luminance level. The tunnel is divided into threshold, transition, interior and exit zones and lighting levels are determined separately for each. Suitable lamps for tunnel lighting are fluorescent and high pressure sodium lamps. The guidelines also make recommendations for the construction and presentation of the entrance and exit roads to enable continued clear visibility. Daylight screens may also be employed in the threshold zone to reduce the artificial lighting used.