> I am curious what this deal about sunscreen is if normal air can
supposedly
> block most of the nasties, there must still be a somewhat damaging band
that
> isn't sufficiently blocked, otherwise I wouldn't think scientists would be
> so concerned with upper atmospheric ozone.

The UV from a mercury vapor tube is much shorter wavelength than the UV that
gets thru the atmosphere and causes sunburn.  This longer wavelength "near
visible" UV is what UV coatings on glasses and UV filters from cameras are
intended to filter out.


********************************************************************
Olin Lathrop, embedded systems consultant in Littleton Massachusetts
(978) 742-9014, olin@embedinc.com, http://www.embedinc.com

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