Q&A Germicidal Air Purifiers

For optimum IAQ and most efficient performance, the devices should be run continuously if possible.

Not always. The blue color does not come from the UVC energy but rather from argon gas inside the Emitter. A blue glow indicates that the Emitter is turned on, but it does not provide an accurate measurement of UVC output. That's why you should change UV lamps annually - even if the blue glow still appears to be bright.

UVC Emitters do not require cleaning as part of normal operation; however, cleaning is recommended if the quartz has been touched during installation. Use 99% pure alcohol and a lint-free cloth.

For large or critical applications, change out should be performed when Emitter output decreases by 40% as measured by our radiometer, after about 9,000 hours or 12 months. For installations with no radiometer, change Emitters annually (after about 9,000 hours) Our GeneralAire UVC lamps have QuartzCoat® Durability Effective Lamp Life 18,000 hours (2 year lamp replacement)

Dispose of them as you would any fluorescent tubes, in compliance with your local or state codes.

UV-Germicidal Light uses ultraviolet energy. UVC energy penetrates even the tiniest microbe to destroy its DNA, killing or deactivating it.

No. UV-Germicidal Light's non-chemical energy destroys organisms without producing toxic ozone, fumes or secondary pollution. It poses no risk to people, furnishings or equipment. (Direct exposure to the light itself is not recommended.)

Absolutely! UVC products have been installed in buildings all over the U.S. and Asia - including hospitals, schools, offices, public buildings, food processing plants, electric utilities and residences. View the Case Studies section of our website for details.

Most UV-Germicidal fixtures are designed specifically for installation in HVACR applications. On existing systems, infestations always exist. Therefore, the best results are obtained when the light is located downstream of and facing the coil. In this location the user can expect the highest efficacy in eliminating surface (coil and plenum), drain pan and airborne microbes. On new systems, it can be placed either up or downstream of the coil and aimed at the coil.

No, installation instructions are available for every model, and CAD layout drawings are often provided when we are informed of dimensional specifics. Depending on the fixture size and style, installation time can average about 15-20 minutes per fixture.

UVC will degrade all of the organic material on and within a coil, usually within 30 days or less. Prior cleaning of the coil is not necessary, and may delay the benefits of UVC.

Yes, NEMA 4x (water and rustproof) style fixtures use single ended Emitters that are easy to install in rooftop systems.

There are several ways to demonstrate the many things taking place: One is to use a contact plate containing specialized agar before the lights are installed. Thirty days after the lights are installed repeat the procedure and compare results. A visible reduction of mold will be seen in a very short period of time. Coil pressure drop will fall, and can drop as much as 30% in 30 days or less (depending on coil cleanliness and water activity). The system's airflow will usually increase as a result. Drain pans and drain pan water become significantly cleaner. All line-of-site surfaces, i.e. insulation, will start to look like new. Most of the space odor will disappear and the air will seem fresher.

UVC is only harmful under prolonged direct exposure - which is not generally an issue, since the devices are installed inside air conditioning equipment or are otherwise shielded to prevent exposure. Use of safety goggles and gloves is recommended as a precaution during installation to protect the eyes and skin.

No, UV-Germicidal devices do not produce ozone or other secondary contaminants.

In commercial, industrial or institutional buildings, a Steril-Aire UVC installation offers the most rapid payback in the industry. A typical installation can pay for itself in a few months and save thousands of dollars thereafter in energy and maintenance costs. This is possible because the devices continually clean coils, drain pans, plenums and ducts, reducing or eliminating costly cleaning programs. HVAC energy costs are lowered by improving heat transfer and increasing net cooling capacity. General IAQ is improved for better productivity and less absenteeism. Product quality, shelf life and yield in processing plants are improved as well.

No, a UVC fixture is an air conditioning component that is used in addition to other system parts. These include the coil, heating core, fan, dampers, humidifiers, filters, etc. All are designed to do some form of work within the air handler or on the air.

Yes, in an infectious disease application the efficiency and location of a filter should always be a concern. The filter goal is to provide a reduction in the total number of microbes. However, viruses can be as small as 0.02 micron, so the target organism needs to be known to provide a predictable result. More importantly, filters do not abate microbial growth on coils, in drain pans or in plenums and ductwork. UV-Germicidal devices do.