Translating the LED literature into good SSL design

July 28, 2017
How I made the leap from an impromptu Spanish lesson to how we communicate and interpret information in the SSL design community...  

Last night on the way to pick up dinner, I attempted to give my husband some very basic Spanish lessons and we nearly ended up in tears of laughter as he failed to repeat back to me exactly the pronunciation that I delivered. (I’m no phenomenal teacher; I’ve maintained some decent level of comprehension but my vocabulary is limited since I haven’t studied Spanish for, oh, 20 years. But my pronunciation is pretty good, in the academic sense.) Apparently, to his ear “puertas” sounded like “huertes.” I don’t even know what word that is and I’m afraid to look it up. The incident made me wonder about the difference between what is being communicated and what is being interpreted. It’s certainly open for discussion!

I’m referring to a recent draft report publicized by the European Union (EU) Scientific Committee on Health, Environment and Emerging Risks (SCHEER). Chief editor Maury Wright reported on this just a few days ago, and I’ve been ruminating on it ever since. Now, of course, I am pleased to see that a respected science-backed organization has been charged with and done its due diligence on investigating purported health risks of LED lighting. And knowing that this is an 84-page report (links to PDF), there is a lot more detailed information than what we as a media outlet can report to our audience. But a couple of notes right at the outset of the draft report stand out to me in bold LED lights (no neon here):

Additional articles on outdoor SSL design & light pollution:

“The search of the literature for the long-term impact of LED emissions on human health did not identify any studies since the technology has been recently distributed on the market for the general population. Because the technology is still evolving, it is important to continue monitoring the scientific literature.

“The SCHEER concludes that the available scientific research does not provide evidence for health hazards to the eye or skin associated with LEDs when the total exposure is below the international agreed eposure[sic] limits (ICNIRP). However, issues in terms of flicker, dazzle, distraction and glare may occur.

“It is expected that the risk of direct adverse effects will increase if these limits are exceeded. However, there is insufficient information in the scientific literature on the dose-response relationship for adverse health effects for optical radiation exposure of the healthy general public.”

Note that these comments in the initial summary are about potential photobiological effects, as well as the impact on skin. Also note that the document is labeled a “preliminary opinion.”

The report draft does go on to outline specific scenarios such as automotive exterior LEDs that tend toward blue-rich light, glare, beam distribution, intensity characteristics, and area illumination viewing angles. The point I am getting at is that a “clean bill of health,” as our partners at Lux put it, is only one part of the information communicated.

My interpretation is the report findings reinforce that, when designed within appropriate tolerances and applied with the utmost care for light delivery and emissive display technology, LEDs have not been shown to promote any health or safety risks. Eye-safe is not the same as comfortable. Ask any of your acquaintances who report increased light pollution in their residential areas due to poorly planned and executed lighting retrofits. Responsibly developed products and carefully considered SSL design will ensure the comfort and safety of those who use them.

*Editor’s note: I overcame my fear of Googling into the unknown on my work PC and there is no such word as “huertes” in Spanish. There is, however, “huerta,” which means “orchard.” I’m relieved.