Germicidal Lamp Technology

Across the spectrum of companies selling UV equipment for germicidal applications, you will come across several different types of lamp technologies and configurations. Some are newer technologies; some are variations of old technologies. This section will explain the difference in some of the more common lamps you may come across.

Essentially, all UVC lamps consist of a quartz envelope containing mercury and other gases and electrodes. When the lamp is struck, the energy between the electrodes excites the mercury into a vapor, which produces C-band ultraviolet energy. All germicidal lamps currently being used in mainstream HVAC applications are low-pressure lamps. Within this “low-pressure” classification are the following types:

Hot Cathode – an older technology (not very common anymore), which uses a softer glass envelope (which devitrifies faster) and smaller electrodes (which put out less intensity and last shorter than other lamps). The trade off is that they are rather inexpensive, in comparison to Slimline or High Output lamps.

Slimline – the most commonly used germicidal UV lamps. They utilize a much harder quartz envelope and bigger electrodes than Hot Cathode lamps. A Slimline lamp can have a useful life up to 15,000 hours and produces almost two times the intensity of a hot cathode lamp of the same size.

High Output – essentially still Slimline lamps, but they use a heavy-duty electrode and slightly different gas mixture to produce 100% more UV intensity than an equal length Slimline lamp while still maintaining an effective life of up to 15,000 hours. The majority of American Ultraviolet Company's UVC fixtures for HVAC applications use High Output germicidal lamps. More information on High Output lamps appears below.

Read about the NEW Eliminator 1 UV Germicidal Lamp System!

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