Operational UVB-1/UVA-1 Frequently Asked Questions
1. I am interested in the DNA damage action spectrum of UV-B and not the erythemal action spectrum. Can I use a correction factor with the UVB-1 instrument's output to calculate irradiance using this action spectrum?
Yes. Each UVB-1 and UVA-1 instrument includes our UV_Calc modeling program that lets you model other action spectrums and compare the UVB-1 measurements to Green's model. UV_Calc is also sold separately.
2. Owners of UV-B networks would like to know what instrumentation is required for making routine calibrations of the Model UVB-1.
rather complicated area of radiation physics. First of all, you don't calibrate broadband UVB-1 instruments using irradiance standard or arc lamps. The spectral output of FEL lamps is wildy different than the solar spectrum. What you do is calibrate a spectroradiometer using a FEL lamp, then you co-locate the spectroradiometer with a pool of about five closely matched broadband instruments and using the sun, transfer the calibration (a UVRSS or U-1000 will work for this, in the past we've also used Richard McKenzie's own spectroradiometer as a check). Please direct them to chapter 4 of the attached UVB-1 manual which outlines the procedure. You should read this before meeting with them.
This will be far more expensive path if they do not own a UVRSS-1024. In some real sense this is a very good reason to buy a UVRSS, it permit you to derive calibration constants directly, (usign the same transfer source, the sun). We sell the PFC-5001 lamp calibrator as an accessory to the UVRSS (does not work standalone).
Most users pay us the cost calibrate them at the factory. NIST/PTB/NPL are highly competent labs, but it will be expensive. In the US the specific NIST lab to talk to is the CUCF - have them look at:
CUCF calibrates all of the USDA's broadband UVB-1s for Colorado State (who runs the US Dept of Agriculture's UV-B monitoring program.)
The UVRSS can produce ozone data, (see page 3-23 of the manual for information.) We have compared the UVRSS favorably with Dobson measurements taken near Boulder, Colorado.
The monitor is able to measure HCHO in Air and Water samples. Both functions can not be separated. The input line for the analysis of HCHO in the liquid phase is also used to calibrate the instrument itself or its internal HCHO- permeation source for automatic calibration.
4. I want to set up a UVB-1, MFR, UVMFR, or SPUV site and only download data every few days on my YESDAS-2. Is unattended operation doable? What about the TSI and RSS?
Yes, absolutely. For radiometers such as the UVB-1, MFR-7, UVMFR-7 and SPUV-10, the YESDAS supports automated remote unattended operation. However, depending on the number of instruments, you will likely want to order the PCMCIA-2 memory card option.
For our TSI and RSS instruments, you can expect to collect anywhere from 1 to 32mb of data per day, depending on data rates. Thus a local PC or a 24-hour, 7 day a week Internet connection is good to have. In cases where it is infeasible to have a network connection, the TSI-880's optional DSM-420 data storage module supports 420Mb of removable storage.
5. We also own your UVB-1 pyranometer. Could you explain any benefits of obtaining the TSI working in conjunction with it.
Clouds affect UV to a high degree. There has been interest in trying to estimate UV from % cloud cover, but at the moment this is an academic area of research. In principle, it should be possible to directly correlate the two measurements, enhancing confidence in the measurements.
Yes. Although mainly used above water, the UVA-1/UVB-1 can handle shallow depths (1 m) for periods of hours to days. The instruments are sealed and have on-board desiccants. You will find that the water's surface and suspended aquatic material tends to attenuate UV-B data in strange and unpredictable ways, mainly as a function of turbidity. A TSP-700, MFR/UVMFR, or SPUV cannot be used underwater.
7. What is the ambient temperature operating range of the radiometers (UVB-1, MFR/UVMFR and SPUV? Will they work in the arctic?
YES has successfully deployed MFR and SPUV systems running from the tropics to Point Barrow, Alaska. However, above 75° north or south latitude you won't be able to make direct-normal or diffuse measurements (a SPUV works just fine above this range but requires a tracker). The SPUV working temperature range is -50° to +50° ; the MFRs working temperature range is -35° C to +40° C. But extreme wind loads can decrease the range slightly. If you can protect the instrument from wind and add additional infrared heaters for cold operations it can work at much lower temperature ranges, as the MFR Point Barrow installation indicates.
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This page was last updated on Monday, September 11, 2006 .