Re: Tungsten and Mercury light

Terry King (101522.2625@CompuServe.COM)
10 Oct 96 12:57:46 EDT

Bob said:

> Some incandescent bulbs contain halogen gas which results in a greater
>UV output. Museums do not like them for illuminating that which might fade.

Are these the generally low voltage ( 6 V ) tungsten lamps often used in the
home as spot lights and in headlights ?

What proportion of UV are they giving out ? How do these compare with
standard voltage higher wattage halogen spot lamps of the same design used in
shop windows and my kitchen ?

If they are giving off more UV, how much more ? Is it unwise or unhealthy to
use them in the home or, contrariwise, would one recommend them for gum ?

I have also assumed that tungsten UV ' health' lamps work by filtering out the
unwanted 'light' which results in low UV output and high heat. Are there any
other significant factors ?

As a rider to the low pressure (fluorescent) / high pressure mercury vapour
discussion,how much does the lower wave spread and output of the fluorescent
lamp put it at a disadvantage compared with the higher output and wave spread of
the graphic arts high pressure MV UV lamp ?

Given Judy's 'nasty don't touch' point are the amounts of ' nasties' in
fluorescent lamps so low that even the US safety persons do not consider it
necessary to mention the risks in the packaging ( I assume that the practice is
the same as in the UK ).

I ask because some of the certainties do not appear to be as certain as they
used to be.

Terry King