UVC: Frequently Asked Questions

What is UVC radiation?

“UVC radiation is a known disinfectant for air, water, and nonporous surfaces. UVC radiation has effectively been used for decades to reduce the spread of bacteria, such as tuberculosis. For this reason, UVC lamps are often called "germicidal" lamps.” – FDA: “UV Lights and Lamps: Ultraviolet-C Radiation, Disinfection, and Coronavirus”

How long has UVC technology been used for germicidal irradiation to improve air, water and surface disinfection?

“Like electricity, ultraviolet light is as old as the universe. It just took someone to notice. In 1877, British Physiologist Arthur Downes and scientist Thomas P. Blunt noticed. They put solution-filled test tubes outside and discovered that sunlight could kill and inhibit the development of pathogenic bacteria. Some 25 years later, the German Ophthalmologist Ernst Hertel built on this knowledge, determining that light in the UV-C wavelength, rather than UV-A or UV-B, is the most effective for killing microorganisms.

In the 1930s and 1940s, William F. Wells, a Harvard University sanitary engineer, made a significant stride in the knowledge and application of UV-C light for disinfection by proving its effectiveness in killing airborne microorganisms. In 1936, Dr. Deryl Hart experimented with UV-C to disinfect an operating room at Duke University Hospital. He reported an 11.38 percent reduction in the rate of postoperative infection rates. Throughout the next few decades, UV-C was applied in schools and hospitals across the country, proving its ability to inactivate microorganisms and bacteria.” – UV Resources: “UV-C Lamps – A Short (Wave) History”

Is UVC effective against viruses like COVID-19?

“Radiation disinfection, especially ultraviolet (UV) radiation, is another well-known inactivation approach for all known microorganisms and viruses that offers some advantages over liquid disinfectants and heat sterilization. It can be performed automatically and employed to disinfect surfaces, liquids, air and rooms, and it is also very energy efficient.” – National Center for Biotechnology Information

“When used in combination with other mandatory air treatment modes, UVC provides an incremental benefit. For example, if a particulate filter removes 85% of a given agent in an incoming airstream and a UVC system with a single-pass efficiency of 85% for the same contaminant is installed in series with it, the combined filter/UVC system would have a combined single-pass capture and inactivation efficiency of approximately 98% (i.e., the incremental benefit of adding an 85% efficient device is only 13%).”




“UVC radiation has been shown to destroy the outer protein coating of the SARS-Coronavirus, which is a different virus from the current SARS-CoV-2 virus. The destruction ultimately leads to inactivation of the virus.” – FDA


How can UVC be used to safely reopen schools?


– Washington Post


Why isn’t UVC more commonly used in the healthcare industry?

“This has to do significantly with human perceptions, according to Edward Nardell, a Professor of Environmental Health, Immunology, and Infectious Diseases at the Harvard TH Chan School of Public Health. According to Professor Nardell, there is a barrier of fear associated with UVC radiation, even though UVC radiation does not penetrate the skin and eyes well. Second, there is a lack of familiarity: biomedical engineers and healthcare professionals are not taught much about germicidal light during their professional training.” – Health Europa

Is UVC radiation safe?

“UVC can irritate skin and eyes, which is why the light is usually restricted to above people’s heads, or for use in unoccupied rooms. The irritation usually clears up within a couple of days. The safety of UVC ‘is really long established,’ Dr. Nardell said.” – The Washington Post

UVC fixtures have louvres on them to prevent the light from striking people, skin and eyes, and they are installed at a “minimum ceiling height of 8 ft (2.4 m) and the fixture bottom mounted 7 ft (2.1 m) above the floor.” – Global Health Delivery Online

cloud-syncearthbullhorn linkedin facebook pinterest youtube rss twitter instagram facebook-blank rss-blank linkedin-blank pinterest youtube twitter instagram