Date:Jan 22, 2021

Q: What percentage of ultraviolet light can glass block?

A: Ordinary glass (for windows) is transparent to ultraviolet light (UV-A) with a wavelength of about 330 nm. The transparency is very high, so almost all UV-A light passes through the glass. Below 330 nm (UV-B and UV-C), almost 100% is blocked by ordinary glass.


Q: I know that water purification with 254 nm ultraviolet light requires 1/100 watt-second per square centimeter. What is the dose of air?

A: Now, most regulatory agencies stipulate a fluence or UV dose of 40 mJ/cm2 (please note that 1 mWs = 1 mJ) to ensure that any pathogenic microorganisms are inactivated by at least 4 log. Since the applied energy density or UV dose is independent of the medium, this requirement also applies to air. However, I do not know any regulations regarding UV air treatment.


Q:  When disinfecting the water, will the temperature of the water and the temperature of the lamp affect the UV output intensity? Does the UV lamp have an optimal operating temperature and maximum and minimum thresholds?

A: Yes, water temperature does affect the UV output of low-pressure UV lamps (it has little effect on low-pressure high-output or medium-pressure UV lamps). The best operating temperature for UV lamps working in the open air is about 40 degrees Celsius (104 degrees Fahrenheit). At 20 C (68 F), the output drops to about 50%, and at 0 C (32 F), it drops to about 10%. When the other end is wrapped in a quartz sleeve with water, the effect will not be too great. The optimal water temperature is about 22 degrees Celsius (71 degrees Fahrenheit), and at 0 degrees Celsius (32 degrees Fahrenheit), the output drops to about 80%.


Q: I only have 110V main power supply. Is the voltage of these lights higher than this voltage?

A: The lamp voltage is provided by a power supply with 110V input (sometimes called a ballast or EPS). The output voltage of the lamp is handled by the power supply.

Q: I need to place a row of UV lamps in the air conditioning duct. Is this possible?

A: Yes, this is a very safe way to use UVC because the lamp is completely enclosed. uv technik is dedicated to HVAC systems.


Q: We need to sterilize banknotes or documents with UVC. is it possible?

A: It is theoretically possible, but all surfaces must be illuminated without illuminating the operator.


Q: I want to disinfect fruits and vegetables with UVC in the cabinet. is it possible?

A: Yes, but you need to make sure that all surfaces are illuminated. No part of the object in the shadow will be processed. If you have a conveyor belt, it will be easier to use a uv tunnel with a vibrating belt. This will ensure complete exposure while protecting the operator.


Q: I need a delivery line with a dose of 30mJ/cm2 UVC. Can you tell me how many lights and what power do I need?

A: Yes, we can calculate with experienced UV engineers.

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