What type of glass blocks UVB?

[RandyMarsh]

Just thinking about it today since it's so nice, but I have a super old house with old old windows in it, they don't even block REGULAR weather, there's no chance they block any actual Sunshine spectrums, anyone know what year glass windowpanes started to get good? Right now I'm enjoying having Franklins light off during the day and he loves his windowsill!

This is just out of curiousity really not any actual need

 

[LLLReptile]

They all block out UVB rays - old windows don't block out UVA much, though. You'll find lots of info about this by simply googling it, although the info is primarily geared towards human skin care and/or tattoo fading.

For example:
http://www.smartskincare.com/skinprotection/uv-indoors.html
http://www.drbaileyskincare.com/blog/do-uv-sun-rays-go-through-windows/
http://cancerhelp.cancerresearchuk....n-glass-block-sun-rays-that-cause-skin-cancer

All of those sites state that glass blocks out UVB, but rarely UVA. UVA is a stronger wavelength and makes it through, but unfortunately does not trigger D3 synthesis in reptiles. UVB is needed, and does not make it through glass. Even screen can significantly filter it - testing bulbs here in the store, the screen can filter out up to half of the UV output of a bulb.
(please note those were all just grabbed off google a minute ago - I didn't thoroughly read them, but they do give a snippet of how much info is out there)

Here's a chameleon forum discussion about it as well.
http://www.chameleonforums.com/glass-uv-technical-explanation-74557/

Hope that helps!

-Jen