Frequently Asked Questions

Germicidal UV (GUV) refers to using ultraviolet radiant energy to inactivate bacteria, mold spores, fungi or viruses. When the process is applied in a given location, it has generally been referred to as ultraviolet germicidal irradiation (UVGI). Because of the public’s concern about ionizing radiation (e.g., X-rays and gamma rays), the term GUV avoids needless concerns about a link with that type of radiation. Another non-technical term is germicidal light, although “light” is technically only visible radiation.

Germicidal UV (GUV) damages nucleic acids (DNA and RNA), thus preventing replication and leading to the death of virtually all bacteria and inactivation of all viruses—both DNA and RNA types.

Bacteria and viruses vary somewhat in UV susceptibility, with environmental organisms, fungal spores, and mycobacteria being relatively harder to kill than more rapidly replicating and non-environmental microbes and most bacteria. But even fungi are effectively killed with high-dose UV, which is used, for example, to treat fungal contamination of air conditioning systems. GUV can be most effectively used to disinfect air in the upper room where ceiling height permits, but can also be used in ventilation ducts and room air cleaners, as noted. Upper-room GUV is considered the most effective application for room air disinfection, where feasible.

(Commonly used GUV lamps generate predominantly 254-nm UV radiant energy, which is close to the peak germicidal wavelengths of 265 to 270 nm – both in the UV-C range, compared to the longer-wavelength ultraviolet (UV-A and UV-B) in sunlight)

Each of our Blue Halo™ products come with an air circulation system that cycles air through a UV-C disinfection chamber. UV-C kills living bacteria, mold, and inactivates viruses rendering them non-infectious. Since viruses are technically not living organisms we should correctly say "inactivate viruses." Individual, energetic UV-C photons photochemically interact with the RNA and DNA molecules in a virus or bacterium to render these microbes non-infectious. This all happens on the microscopic level. Viruses are less than one micrometer (µm, one-millionth of a meter) in size, and bacteria are typically 0.5 to 5 µm.

Yes. There are no significant differences between the installation of our products and the installation of others that an electrician or handyman might be familiar with.

Yes! Our Blue Halo™ products still remain high quality LED lights manufactured by one of the most well known lighting manufacturers in the world.

(NOTE: Some of our products are not lights, such as the 2x2 Upper Air and the UVC Universal Flushmount which are high quality, yes, but are purely air disinfection products and do not illuminate a space)

The official position of the World Health Organization (WHO) is that this virus is spread by contact with large respiratory droplets, directly or indirectly by touching contaminated surfaces and then touching the eyes, nose, or mouth. However, research is underway to determine the degree of airborne spread—meaning virus in particles so small that they remain suspended in air. Such aerosol results from the evaporation of larger respiratory particles generated by coughs, sneezes, ordinary speech, singing, and possibly by faulty plumbing systems, as occurred with the severe acute respiratory syndrome (SARS) virus. How much of the virus responsible for COVID-19 is spread by the airborne route is not clear, but recommendations for healthcare workers to use fitted respirators, not surgical masks, reveal official concern for airborne transmission. The possibility that inhaled virus may result in more-severe lung damage than acquisition by other routes—for example, via the mouth, nose, or eye—is currently being investigated.

This is important, but difficult to answer in a simple fashion and it depends on how the microbes were made airborne, e.g., from a sneeze or cough, or by being blown up from surfaces or dusted off clothes. The smallest particles (1- to 5-µm droplet nuclei) can remain airborne much longer than cough droplets—for many minutes or even hours.

Yes, if the virus is directly illuminated by UV-C at the effective dose level. UV-C can play an effective role with other methods of disinfection.

Yes, UV-C kills living bacteria, but viruses are technically not living organisms; thus, we should correctly say “inactivate viruses.” Individual, energetic UV-C photons photochemically interact with the RNA and DNA molecules in a virus or bacterium to render these microbes non-infectious. This all happens on the microscopic level. Viruses are less than one micrometer (µm, one-millionth of a meter) in size, and bacteria are typically 0.5 to 5 µm.

In the U.S., the Centers for Disease Control and Prevention (CDC) has provided guidelines for the use of UVGI lamps in upper rooms and air handling units (AHUs) as a supplemental control measure for air disinfection.[5, 6, 7]

[5] Sehulster L, Chinn RYW. Guidelines for environmental infection control in healthcare facilities – Recommendations of the Centers for Disease Control and the Healthcare Infection Control Practices Advisory Committee (HICPAC). 2003;52(RR10):1-42.

[6] Jensen PA, Lambert LA, Lademarco MF, Ridzon R. 2005. Guidelines for preventing the transmission of Mycobacterium tuberculosis in health-care settings, 2005. Morbid Mortal Weekly Rep. 2005;54(RR17):1-141.

[7] Centers for Disease Control and Prevention; and National Institute for Occupational Safety and Health. Environmental Control for Tuberculosis: Basic Upper-Room Ultraviolet Germicidal Irradiation Guidelines for Healthcare Settings. Washington, DC: Department of Health and Human Services; 2009.