My study design is in vivo study using animal model which is mice. Mice are exposed to ultraviolet UVB for 3 minutes. Lamp source that i use: wavelength 302 nm, 15W with the length 50.2 cm.
Given the dose i chose for example 36 mJ/cm2, how to determine ultraviolet lamp output measurement? Is this related to Keiz equation?
Can someone explain to me what is the difference between irradiance and fluence rate? Is dose term actually the same thing as fluence rate?
I have no idea how to answer your specific question, but I will warn you that the output of a UV bulb diminishes over time. That is, the output of a new bulb is greater than that of an older bulb.
For example, the UV bulbs that I use in biosafety cabinets for decontamination only have a useable lifespan of 1,200 hours. The older the bulb is the longer the exposure time needs to be.
You might want to consider this in your calculations and either use a new bulb for your experiments or else use a device to measure the actual UV output.
To answer your specific question, and to determine the global output of your UV source, you should use a calibrated spectro-radiometer and take a full spectrum of your UV source at a well determined distance from the first active optical device of your spectro-radiometer (e.g. 50.00 cm).
These measurements will provide you the spectral irradiance of your UV source (in W/m2 nm). The integral of this spectrum will give the total irradiance of the source ( in W/m2). You can calculate the UV dose by integer the global irradiance during a define time.Dose in given in J/m2.
Do not forget that your UV lamp need some time to reach the optimal emission (warming time) and that the UV sources are not constant during long period (usual life time is around 1000 hours, depending of the type of source).
An other important notion is the radiance that depends on the solid angle (W/m2 nm sr).
I hope these few remarks will help you
Didier Gillotay
Fluence rate is the same as irradiance, measured in W/m2, for example. Fluence is the same as UV Dose, measured in J/m2 or W-s/m2, for example. Your previous question is not clear. Is 36 mJ/cm2 the dose you are seeking to impose? The Keitz equation is not accurate for UV lighting. It deviates significantly in the near-field.
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