[westdave]

nick-
All good stuff, but the critical thing about UV is its wavelength - 
anywhere from 10nm to 400nm.
 
Below 300nm, dangerous to people - above that is mainly UV-A which is not 
too bad - its like cholesterol - there is bad (LDL or all UV *except* UV-A) 
and "not so bad" (HDL or UV-A) :)

westdave

where did I come up with that stuff about the atomic bombs and a glass windshields

in his book" surely you're joking Mr feynman"

Richard feynman said, that's where he was sitting during the first atomic blast ,in a jeep watching from behind the windshield to block out the UV

(yea ,it would be much more fun to just make things up. but sometimes I can back them up!)