Measuring UV

Carlyn Hammons <carlyn.hammons [at] thc__state__tx__us> writes

>...  I am in search for some obscure information and hope
>that someone here might be able to help.  I know that there is a
>very complicated formula for determining microwatts per lumen using
>the combination of a lux meter and a UV meter which gives readings
>in microwatts per square centimeter.  Does anyone recall this
>formula?

This is how you get there:

    1 lux = 1 lumen per square m (by definition)
    1 square m = 10,000 square cm

Therefore:

1 microWatt per square cm = 0.0001 microWatt per square m = 0.0001
microWatt / lux per lumen

This gives you:

    1 microWatt per lumen = 10,000 microWatt per square cm and lux

So, what you need to do is:

    Take your UV meter reading in microWatt per square cm
    Multiply by 10,000
    Divide by your luxmeter reading (in lux)
    Now you have your microWatts per lumen

Example:

    Your UV meter reading is 0.3 microWatts per square cm
    At the same time and in the same place you measure 50 lux
    Calculate: 0.3 x 10'000 / 50 = 60
    This is a reading of 60 microWatts per lumen

Good luck,

Kilian Anheuser
Conservateur responsable du secteur
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Rue Charles-Galland 2
Case postale 3432
1211 Geneve 3
Suisse
+41 22 418 2520,
Fax: +41 22 418 2511


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                  Conservation DistList Instance 20:13
                 Distributed: Friday, September 8, 2006
                       Message Id: cdl-20-13-006
                                  ***