Can grow lights cause eye damage?

March 13, 2013 8:05 PM

I have a nice 4' long fluorescent grow light set up in my study. I am busy starting up plants for spring and it is on 14 hours a day. The light is working perfectly and seedlings are growing beautifully, but I am wondering about any possible damage it might do to my eyes, as I spend many hours a day in the office working. The hood that came with the light is very narrow so a lot of light reflects up into the room, though I am not looking directly into it, the reflected light is always visible out of the corner of my eye. Should I be worried about it? My main concern is exposing my eyes and skin to UV light and damage, but could there be other things I should be worried about too. Can I fix the hood by say sticking some foil on it so less light bounces up into the room and is directed downwards? Or should I just move it to another room? I have no other heated rooms in my house at the moment it could go in so I worry about the seedlings Thanks in advance for any help or suggestions.
posted by wwax to Home & Garden (5 answers total)

If they give off ultraviolet light, then yes, it is bad for you, and it appears that even compact fluorescent lights might give off enough UV to be harmful. I'd move it. Or wear sunscreen.
posted by overleaf at 8:43 PM on March 13, 2013

If it's not causing noticeable tanning/sunburn, and it's not making your eyes feel itchy, then I (not a doctor) would be fine with it. It might slightly increase your UV exposure but the positive effects on your mood might outweigh the risks. If you can see the glowing bulb, I would make a foil shield like you suggested just so the brightness doesn't bother you. Foil blocks UV light just like it blocks visible light.
posted by sninctown at 8:51 PM on March 13, 2013

Would there be a parts number or identifying information on the bulb?
posted by sebastienbailard at 1:13 AM on March 14, 2013

Best answer: 1- Look at the bulb's model number and find out what it's UV output is supposed to be. Some grow lights purposefully put out UV.

2- Unless you are using a very high wattage bulb, the amount of UV light getting out is probably not going to make a difference compared to incidental exposure from the sun.
posted by gjc at 6:26 AM on March 14, 2013 [1 favorite]

Best answer:

overleaf: If they give off ultraviolet light, then yes, it is bad for you, and it appears that even compact fluorescent lights might give off enough UV to be harmful. I'd move it. Or wear sunscreen.

FTFA: Rafailovich explained that at close range, around a foot or so, CFL exposure is "the equivalent of sunbathing at the equator." This may not be cause for alarm for those who have CFLs mounted in ceiling fixtures, but it should be a concern with desk or table lamps.

The UV exposure drops off as an inverse square of distance, so staring at the bulbs from 2' away is four times safer than staring at them 1' away. It sounds like you aren't using this light for direct lighting on your desk, so I suspect your exposure is more like dozens or even 100's of time lower. In other words, as long as your direct line-of-sight to the exposed bulbs are greater than your arm's length, you probably get more UV by walking outside in June than by having these bulbs in your room. And if you are momentarily within 1' of the bulbs, it's like staring at a dazzlingly bright cloud on a sunny day. Just don't stare all day, every day, at those clouds.

You are fine. The bulbs are fine. IANAD, but I am an optical engineer who has studied eye safety regulations and applied the calculations to prove our light sources did not risk anyone's health. 99% of the doctors in the world wouldn't actually know how to do this, so all they could do is guess.
posted by IAmBroom at 10:42 AM on March 14, 2013 [1 favorite]