Aug 4, 2017: The Illuminating Engineering Society (IES) has issued a position statement that disagrees with some aspects of a policy statement issued last year by the American Medical Association (AMA) on outdoor lighting.
AMA Policy H-135.927 “encourages minimizing and controlling blue-rich environmental lighting by using the lowest emission of blue light possible to reduce glare” and “encourages the use of 3000K or lower lighting for outdoor installations such as roadways.”
IES Position Statement PS-09-17 points out, among other things, that CCT “is inadequate for the purpose of evaluating possible health outcomes” and that the AMA recommendations “target only one component of light exposure (spectral composition) of what are well known and established multi-variable inputs to light dosing that affect sleep disruption, including the quantity of light at the retina of the eye and the duration of exposure to that light.” The IES statement notes that increased melanopic content is “a more widely accepted input to the circadian system associated with higher risk for sleep disruption and associated health concerns,” and that “LED light sources can vary widely in their melanopic content for any given CCT.”
The IES position statement offers valuable, science-based information to aid in the ongoing discussions regarding LED street lighting and blue light. Visit the DOE website for additional online resources, including an updated table of blue light characteristics for various outdoor lighting sources.