Are quantum board LED grow lights a bad idea for SAD light therapy?
October 4, 2020 2:22 PM Subscribe
Last year after moving cities I knew I’d have to up my game to fight SAD. I decided to try and build a morning routine around some indoor gardening (started with sprouts) under a SAD lamp.
It was alright, so I expanded, bought some grow lights and started some containers. My old awkward SAD light is hanging out dusty in a corner. I spend maybe 20-30 mins puttering under these lights, 4-5 mornings per week. They are mostly white spectrum LEDs but I know these units also have some blue / red / IR / UV leds in the mix.
However, this previous question made me realize I should do a safety check. Internet’s not being super helpful. So... should I give up trying to get my daily light therapy from “quantum board” grow lights?
Response by poster: I have two lights hanging above a couple shelves. The lights are about 2’ from soil level and about the same from me, when I’m attending to plants.
posted by sixswitch at 5:13 PM on October 4, 2020
posted by sixswitch at 5:13 PM on October 4, 2020
Response by poster: Mars Hydro are the lights I have, yeah.
posted by sixswitch at 8:32 PM on October 4, 2020
posted by sixswitch at 8:32 PM on October 4, 2020
According to the Mayo Clinic, you want a lot of photons, any color, and little UV.
https://www.mayoclinic.org/diseases-conditions/seasonal-affective-disorder/in-depth/seasonal-affective-disorder-treatment/art-20048298
Grow lights are a lot of photons (mostly red and blue, no green), and little UV.
You and the plants have the same needs.
posted by nickggully at 8:55 PM on October 4, 2020
https://www.mayoclinic.org/diseases-conditions/seasonal-affective-disorder/in-depth/seasonal-affective-disorder-treatment/art-20048298
Grow lights are a lot of photons (mostly red and blue, no green), and little UV.
You and the plants have the same needs.
posted by nickggully at 8:55 PM on October 4, 2020
Per the Amazon page you linked, the light's spectrum is this.
Assuming that spectrum is accurate, it has a strong spike in the spectrum at about 440nm.
So the ultraviolet A (UVA) spectrum is considered to be 315-400nm and then UVB and UVC are lower than that (280-315 and 100-280nm, respectively).
So, your light has some violet light, but no significant amount of UVA light and none at all of UVB or UVC.
In short, it's visible light--should be good to go. (Again--assuming you can rely on the spectrum published on that page.)
Want more confirmation, look starting page 1038 here (look under "148 — Electromagnetic Radiation and Fields" and then "Ultraviolet Radiation"). This is from a book compiling Threshold Limit Values (TLVs®) for Chemical Substances and Physical Agents and the Biological Exposure Indices (BEIs®) that were adopted in 2012 by the American Conference of Governmental Industrial Hygienists.
So if you look at their charts (see p. 1041 for example), the danger drops off exponentially as frequency rises 320nm to 400nm. And then frequencies above 400nm aren't even listed (ie, there is no concern about them at all).
So all the frequencies your light outputs, are exactly in the zone of "no concern at all".
posted by flug at 9:06 PM on October 4, 2020 [1 favorite]
Assuming that spectrum is accurate, it has a strong spike in the spectrum at about 440nm.
So the ultraviolet A (UVA) spectrum is considered to be 315-400nm and then UVB and UVC are lower than that (280-315 and 100-280nm, respectively).
So, your light has some violet light, but no significant amount of UVA light and none at all of UVB or UVC.
In short, it's visible light--should be good to go. (Again--assuming you can rely on the spectrum published on that page.)
Want more confirmation, look starting page 1038 here (look under "148 — Electromagnetic Radiation and Fields" and then "Ultraviolet Radiation"). This is from a book compiling Threshold Limit Values (TLVs®) for Chemical Substances and Physical Agents and the Biological Exposure Indices (BEIs®) that were adopted in 2012 by the American Conference of Governmental Industrial Hygienists.
So if you look at their charts (see p. 1041 for example), the danger drops off exponentially as frequency rises 320nm to 400nm. And then frequencies above 400nm aren't even listed (ie, there is no concern about them at all).
So all the frequencies your light outputs, are exactly in the zone of "no concern at all".
posted by flug at 9:06 PM on October 4, 2020 [1 favorite]
This thread is closed to new comments.
posted by bluedaisy at 3:03 PM on October 4, 2020