UV filters

I have recessed low-wattage recessed halogen lights (Halo housing
#H-1499-T & trim #1420-P) that I use in my the space in my home
dedicated to displaying antique and ancient textiles.  Some textiles
are under UV treated plexiglass, but not all.  The lights have a
round glass lens (about 2" in diameter) between the housing and the
bulb--that is, between the bulb and the space it is shining into.  I
was wondering if it were possible to find lenses that are UV
treated.  If so, how much impact does the treatment have on UV
reduction?  Also, how much impact on UV reduction does dimming the
lights have? Thank you,

Bea Weicker Irvin

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                  Conservation DistList Instance 12:45
               Distributed: Wednesday, November 18, 1998
                       Message Id: cdl-12-45-010
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