Al: Wikipedia may be of assistance:

http://en.wikipedia.org/wiki/Ultraviolet

Wavelength is inversely related to "strength" of electromagnetic
radiation. Shorter wavelengths have more energy than longer ones do; when
using handheld UV lights, the shortwave is very dangerous to eyes and
skin, for example. The longwave UV light is less harmful.

If I remember my physics correctly, UV-A is longwave, and
shortwave is UV-B. Most (not al) glass will stop most (99%+) UV-B, but
allow much of the UV-A to get through. It is possible to buy specially
coated glass that will prevent 99.9...% of the total UV light from getting
through.

Not sure if this helps or not.

Send no e-mail to the address in the header. Spam trap.

-AJHicks
Chandler, AZ