Lighting for museums is a specialised area in lighting engineering usually carried out by experts. Besides illuminating and sometimes even dramatic showcasing of exhibits and visual guidance for observers, lighting aspects relating to conservation are paramount in museums and galleries when it comes to planning and implementation. The sector initiative "licht.de" has released the publication "Museumsbeleuchtung – Strahlung und ihr Schädigungspotential, konservatorische Maßnahmen" (only available in German language) as well as licht.wissen issue no. 18 "Good Lighting for Museums, Galleries and Exhibitions" (in English) for free download at www.licht.de.
Light ought to present exhibits, not destroy them. This requires sufficient knowledge of materials and their susceptibility to radiation of different spectrums (see also chapter "Lighting of retail spaces").
To reduce the damage to exhibits caused by incandescent-lamp heat radiation (tungsten halogen lamps), the International Council of Museums (ICOM) recommends limiting illuminance on exhibits. Regarding maximum UV radiation power, 30 μW/m² are specified for the UVA and UVB ranges. The values can be provided by lamp manufacturers. ICOM thus recommends fluorescent lamps with warm-white light colour and tungsten halogen lamps.
For new installations, LED luminaires are predominantly used today. Their benefits are the complete avoidance of UV components (ultraviolet radiation) as well as a highly reduced IR radiation component (infrared or heat radiation). At the same time, luminaires are available in a great variety of light colours, colour rendering indices, luminous flux levels and distribution characteristics at extensive dimming capability.