Equipment and Design Aspects

Abstract

For the high lighting levels in the threshold zone, pronounced light distributions in the longitudinal direction are needed, which calls for the use of compact lamps. Tubular high-pressure sodium lamps and LEDs are therefore the lamp types most suitable for the lighting of the threshold zone. For the tunnel zones, where lower lighting levels are needed, viz. the transition and the interior zone, long linear light sources are more advantageous. Many tunnels therefore make use of tubular fluorescent lamps for these zones. However, thanks to the high efficacy and long life of LEDs, these types today offer often a more efficient solution. The most important properties of these lamps and of the luminaires in which they can be used, will be dealt with in this chapter. Daylight screens mounted in front of the tunnel that filter the daylight, can sometimes be an alternative to electric daytime lighting of the threshold zone. Such screening equipment will also be discussed in this chapter.