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For the GEEKS in you - How to calculate the UVC dose for given UVC lamp?

The Irradiance formulas for UV Discharge lamps:

A) For a large distance to the lamp we get: The irradiance = (Total Radiation flux (W)/ π2.a2 ——- For (a >> L)

B) At shorter distances the irradiance: The irradiance = (Total Radiation flux (W)/ 2 π.a.L ——- For (a < 0.5 L)

L is arc length of the lamp which is distance between 2 arcs inside lamp tube

- which is 3.35” (85mm) for 4 Watt lamp

a: Is the perpendicular distance between surface & Bulb

Eg: For a 4W Lamp The Total Radiation flux is 0.9 w At 1 meter the irradiance would equal to 9.13 uW/cm2

At 1"/ 2.54cm the irradiance would equal to 6.64 mW/cm2

At 4” (10.16cm) >>>>> the irradiance would equal to 884 uW/cm2

Note: Don’t forget the Mercury UV lamps operate at 254nm wavelength, while the Peak Germicidal effect occurs at ~264nm so you need to correct for the radiation generated by your bulb at 254 nm, which is approximately at 85% of the maximum germicidal effect. So derate you’re calculated irradiance by 15%.

For UVC LEDs 265-275nm this difference is negligible with thanks to Mark Qandil on Jul 01, 2020

Are you buying UVC LEDs and not finding the PCB and Circuit ?

Use our UVC Linear LED Lamp works with any smps 12/24V . You can run 6 different powers on same size LED lamp, and mature to oridering the individual UVC 3535 package LEDs !

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