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From: Patent Tactics, George Brock-Nannestad Hello, confusion is understandable, even from a technical point of view, because the fluorescent lights do contain neon to get the discharge going. However, it is the mercury content that creates the trouble. The mercury discharge has very strong ultraviolet bands at (from memory) 180 (nm) nanometers, 254,1 nm, 300 nm and 360 nm (and some visual ones). The shortest wavelength will create ozone when it irradiates oxygen, as it may, if a quartz burner were used, because quartz is transparent to short-wave ultraviolet. All of these wavelenghts are absorbed by the fluorescent pigment and converted by fluorescence (mainly red-emitting), but not completely. The glass absorbs the two shortest almost entirely, but 300 nm and in particular 360 nm do escape to some degree. For suntan you only want the 300 and 360; the others are damaging. Now, I have never understood why anybody who is responsible for an archive would want to leave lights on; light of any wavelength, and particularly the shorter ones, is very damaging to almost everything from organic pigments to plastics. Museums really concern themselves with light doseage over the lifetime (which is obviously forever) of their collection items. Ceramics hold out well, as do metal objects, but organic matter, ouch! Kind regards, George Shai Drori wrote: > Sorry for the confusion, fluorescent of course (English second > language). Here both words are used to describe the same lighting > source. :-[ > Shai > > Richard L. Hess wrote: > > At 01:28 PM 2010-01-30, Shai Drori wrote: > >> So here is what happened. I would love to hear comments etc. > >> > >> Burnt cd's were stored in jewel boxes on shelves. The room was lit > >> with neon lights 5 days a week from 7am to 5pm. > > > > Neon or fluorescent? > > > > If fluorescent, they have some UV content, I think. Neon doesn't make > > sense--it's orange. > > > > Cheers, > > > > Richard > > > > > > Richard L. Hess email: [log in to unmask] > > Aurora, Ontario, Canada (905) 713 6733 1-877-TAPE-FIX > > Detailed contact information: > http://www.richardhess.com/tape/contact.htm > > Quality tape transfers -- even from hard-to-play tapes.