Day Light, Good Light (03-12-10)

Good mental health depends on soaking up a few rays – and not just outdoors.  Researchers have determined that our mental state is enhanced when we have access to daylight while indoors, and the Society for Light Treatment and Biological Rhythms (SLTBR) met recently to discuss within building exposure to daylight.  The architects, lighting engineers, and scientists who met at the SLTBR session drafted building design guidelines that include:  1) Views from windows should allow people inside a building to see out far enough to monitor the direction of sunlight and the height above the horizon of the sun.  2) It’s a good idea to cycle colors and intensity of artificial lighting to mimic sunlight when it is not possible to bring much direct daylight into a structure.  Sunlight is brighter at midday than at sunrise or sunset and is bluer around noon and more yellowish/reddish at sunrise and sunset.  3) “Artificial light sources, both within public places and private spaces, should be designed and placed so they minimize the amount of light pollution at night, in order to achieve adequate darkness conditions . . . . Darkness is an important determinant of circadian adjustment, as is the gradual twilight transition from darkness to daylight.”

Anna Wirtz-Justice and Colin Fournier.  2010.  “Light, Health and Wellbeing:  Implications from Chronobiology for Architectural Design.”  World Health Design, vol. 3, no. 1, pp. 44-49.