# UVB in the shade?



## gregcalverley0327 (Jun 9, 2013)

I heard animals still can get UVB even in the shade or covered areas outside, just wondering if this was true?


0.3.0 sulcata tortoise 
(Manavi, aspen, Bronx)
1.0.0 Russian tortoise 
(Ivan)
1 Great Dane
(Koko)


----------



## pfara (Jun 9, 2013)

Shade from trees, plants, clouds- yes. Light can still pass through leaves along with UV. It'll be diminished, but still pretty decent depending on how thick the canopy/clouds are. Shade from other materials- unsure. You'd need a solarmeter 6.2 to test the amount of UV penetration.


----------



## gregcalverley0327 (Jun 9, 2013)

Hm okay just sounded interesting 


0.3.0 sulcata tortoise 
(Manavi, aspen, Bronx)
1.0.0 Russian tortoise 
(Ivan)
1 Great Dane
(Koko)


----------



## hunterk997 (Jun 9, 2013)

I think this is true because as long as it's not after sun set, there is still some light. It may not be direct, but the abscence of light is not absolute until it's actually dark.


----------



## pfara (Jun 9, 2013)

No man made light can ever replicate the intensity of the sun (well.. maybe). So since the sun is crazy powerful, the light/uv from it can pass through certain things. Leaves are one of those things; hence why vegetation still grows under massive trees in dense rainforests.




hunterk997 said:


> I think this is true because as long as it's not after sun set, there is still some light. It may not be direct, but the abscence of light is not absolute until it's actually dark.



Light and UV don't necessarily go hand in hand. Light can pass through glass and greenhouses but filters the UV out.


----------



## Millerlite (Jun 9, 2013)

Uv rays also bounce, so if not going though the trees then bouncing through little gaps or angles to get in and under. This happens too on cloudy days, the uv rays get trapped green house effect with the overcast sky's and you can actually get worse sunburn on an overcast day..


I think uv waves are also not visible to the human eye,


----------



## Yvonne G (Jun 9, 2013)

Yes, it's true.

Not really UVB, however, an interesting factoid: I have solar panels on my roof. This a.m. before the sun was shining on the panels, I happened to look at my converter and it showed that I was sending electricity back through the grid. The sun wasn't even shining on the panels.

So, the UV, along with the actual sunshine, is in the air all around us.


----------



## Jd3 (Jun 9, 2013)

I've had 21 spots of skin cancer removed and I've never received more than 1 or 2 minor sunburns. Indirect sunlight is a very real producer of UVA/UVB. 

http://www.cnn.com/TECH/science/9807/14/shade1.enn/

This site shows the uv index for your area, and forecasted too. You'll see that even in low light times it is present!

http://www.uvawareness.com/

And because this is what I link to every time I talk about the sun:
http://youtu.be/_4jgUcxMezM

Wear sunscreen. Every time you're outside. It prevents aging In skin, too! Wear good sunscreen. The best are often store brands! 

/soapbox.


----------



## JoesMum (Jun 9, 2013)

*Re: RE: UVB in the shade?*



gregcalverley0327 said:


> I heard animals still can get UVB even in the shade or covered areas outside, just wondering if this was true?
> 
> 
> 0.3.0 sulcata tortoise
> ...



Yes definitely. I got my worst ever sunburn reading a book on a very overcast, cloudy day in mid summer when I wasn't wearing sunscreen; a painful lesson as a teenager and one that I have never forgotten!


----------



## jaizei (Jun 10, 2013)

There are a lot of variables. In the shade looking out at a sunny area then yes there will be considerable UVB. In the shade where you can't see a sunny spot, then there will be considerably less, if any. 

I measured over 30uW/cmÂ² on my back porch in the shade (compared with ~300uW/cmÂ² in full sun). That's better than a 100w Powersun @ 12" after burn in and initial degradation. Something to keep in mind when using artificial sources of UVB.


----------

