UV glass can't protect against heat, for one 
thing. Improper temperatures are just as damaging 
for any piece of artwork as radiation might be. 
Like the article said--- it's important to never, 
ever hang your artwork in direct sunlight. So how 
much of the fading was due to UV radiation, and 
how much of the fading was due to heat?

However, there's a major flaw that I can see 
right off the top with this study. *The two 
prints being used weren't the same colors.* Reds 
undergo a much quicker deterioration than blues 
do. It was hypothesized that the differences were 
in the modern inks being more "color-fast".

I have to go to work, but I'll try and dig up 
some other studies. :o) But yes, UV-filter glass 
is important to have. For an experiment, all you 
really need is a meter that measures UV 
radiation, a piece of glass, and a piece of UV-
protected glass. You hold the UV meter behind the 
regular glass, and record the number. Then you 
hold the UV meter behind the protected glass, and 
you record that number. The UV-protection is very 
effective; I've done this experiment before. But 
UV radiation isn't the only agent of 
deterioration out there. :o)

-Cres