Recommended levels for building façades and monuments These are currently contained in the CIE Guide to Floodlighting (CIE 93-1993), which provides information on how to use exterior lighting for the decoration of the nighttime urban landscape.22 Building façades and monuments should have a maximum luminance of no more than 1 cd/m2. Buildings should not be illuminated from bottom up, except for historic buildings for which it is impossible to light them from above. In this last case, the light flux should be completely intercepted by the building facade.23
© Federico de la Paz
Recommended illuminance levels for luminous signs and advertisements The recommendations contained in the ”Guide on the limitation of the effects of obtrusive light from outdoor lighting installations” (CIE 150–2003) related to this section can be taken into account as guidance reference. Advertisement luminous signs and billboards not exceeding a luminance value of 4 cd/m2 and a total flux of 5000 lumen in every direction, turned off at the closure of the respective activity can be considered acceptable.21
© ISTIL
The “Guide to the lighting of urban areas” CIE-136-2000 includes recommendations to limit luminaire brightness to avoid glare, setting maximum values according to the luminaire fixture height.
Reference Guidelines In order to develop detailed criteria and recommendations, the following reference guides shall be taken into account: Summary of recommendations for outdoor lighting installation and open enclosures (OTPC-IAC, Oficina Técnica de Protección del Cielo de Canarias). Reviewed in 2008. Summary of criteria to be followed for lighting installations which may have a negative effect on night sky quality. (OTPC-IAC, Oficina Técnica de Protección del Cielo de Canarias). Reviewed in 2008. 21
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A few advanced regulations establish a limit of 1 cd/m2 of luminance for luminous signs, with a total lumen output for each sign of no more than 4500 lm. This Guide is currently being updated by CIE Technical Committee 5.24 The need to limit maximum brightness values allowed for illumination of building façades and monuments has also been taken into account in the ”Guide on the limitation of the effects of obtrusive light from outdoor lighting installations.” (CIE 150–2003).
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