UV monitors

Peter Lundskow <plundskow [at] dnr__state__in__us> writes

>Recently, we purchased a more accurate meter, the UVX Radiometer
>from UVP Ultra-Violet Products (this meter comes with certification
>of calibration)it takes readings in microwatts per cm squared.  I
>have not been able to find any information on how to convert one
>measurement to the other and what safe readings would be for museums
>when measured in microwatts per cm squared. ...

The simplest way to convert from UV power (W/m2) to UV proportion
(W/lm) is to measure the illuminance (lux or lm/m2) at the same
measurement point.  A UV power measurement of 0.375 microwatts per
square centimetre (3.75 mW/m2 or 3750 microwatts/m2) with an
illuminance measurement of 50 lux (at the same point and as
simultaneously as possible) can be converted to UV proportion by
multiplying UV power by the illuminance reading: 3750 x 50 = 75
microwatts per lumen.  The 763 and 764 monitors measure all three
parameters.

Dr Barry Knight has a good posting on this subject in Conservation
DistList Instance 15:43, Monday, December 17, 2001
    <URL:http://palimpsest.stanford.edu/**
        byform/mailing-lists/cdl/2001/1488.html>.

    **** Moderator's comments: The above URL has been wrapped for
    email. There should be no newline.

Arfon Davies
ArupLighting
London


                                  ***
                  Conservation DistList Instance 17:17
                  Distributed: Thursday, July 31, 2003
                       Message Id: cdl-17-17-003
                                  ***