ABSTRACT
Electric lighting plays an essential role in determining the environmental quality of building interiors. Furthermore, the choice of artificial lighting systems and the relationship to daylighting strategies is central to the achievement of energy efficiency. In the design of electric lighting systems there are three levels of initial decisions to be made relating to: • the lighting strategy • the type of lamp • the type of luminaire. In terms of a lighting strategy for commercial situations the choice is typically between providing: • general lighting (uniform illuminance, regular
layout, monotonous effect, independent of furniture layout)
" localised lighting (provides illuminance where it is required, more energy efficient, relocatable systems are preferable to achieve flexible)
• task lighting (with minimal background lighting, typically one third of working illuminance, efficient when high illuminances are required, flexible, permits individual control).
