According to the International Ultraviolet Association (IUVA), UV-C disinfection technologies reduce the transmission of the virus responsible for COVID-19, SARS-Cov-2 infections, as demonstrated by disinfection data and empirical evidence.
With "UV-C" or "UV-C disinfection" we refer, in the germicidal range, to the energy of UV-C light (200-180 nm), different from UV-A and UV-B rays used in tanning beds or in reference to exposure to sunlight.
In fact, as already demonstrated, UV-C rays are able to disinfect air, water, tissues and surfaces of all kinds, and for this reason, if applied correctly, can help in the prevention of infections caused by COVID-19 virus.
Why UV-C rays can help prevent transmission of COVID- 19
Empirical data confirm the disinfected action of UV-C rays, which are able to eliminate 99.99% of bacteria, germs, viruses and fungi present in the air and on surfaces. Precisely because of this disinfectant capacity, UV-C light has been used for more than 40 years in the sanitization of drinking water, waste water, air, pharmaceuticals and surfaces against an entire suite of human pathogens.
Over the years, UV-C technology has been successfully tested on hundreds of types of bacteria and viruses including other coronaviruses: some organisms have proven more sensitive than others, but all viruses and bacteria responded to the appropriate doses of UV rays.
Laboratory experiments have shown that UV-C light is capable of inactivating at least two coronaviruses related to COVID-19, SARS-Cov-1 and MERS-Cov.
The effectiveness of UV-C disinfection depends mainly on two factors:
- the exposure time
- the ability of UV light to reach and neutralize bacteria and viruses in water, air and cracks of different materials and surfaces.
The empirical data obtained from the experiments allow to identify the time and the exposure modalities necessary to inactivate the various viruses and bacteria and to define guidelines for a correct UV disinfection.
IUVA Information Sheet on COVID-19
The IUVA is a non-profit organization founded in 1999, with the aim of developing ultraviolet technology to solve public health and environmental problems.
Following the pandemic and health emergency that has affected much of the world, IUVA has brought together the most important international experts to develop a guide for the use of UV technology and provide a valid disinfection process that can reduce the transmission of COVID-19 virus.
IUVA believes, in fact, that the use of UV-C rays, which has proven effective for the inactivation of the coronavirus SARS-Cov-1, can give similar results also in the treatment of COVID-19.
It has been shown that the COVID-19 virus is able to survive on various surfaces for a variable time depending on the material: on plastic for example it is able to live for at least 3 days; infections from COVID-19, therefore, can be caused not only by contact with infected people, but also by contact with contaminated surfaces.
A multiple approach consisting of normal cleaning and UV disinfection is certainly more prudent and effective in preventing infections. UV-C disinfection can be used together with other technologies as an additional barrier to ensure complete neutralization of all pathogens.
If the virus or beat is not "killed" by the first cleaning or filtration process, it is inactivated by the next UV disinfection process. This sanitization procedure can be adopted in clinical or other contexts to reduce the risks of contagion and consolidate existing protocols.
In addition, according to IUVA and the Center for Diseases Control (CDC) guide provided to hospitals, the germicidal efficacy of UV-C light is affected by several factors:
- the UV-C absorption properties of the surface, suspension or air in which the organism is located;
- the type or action spectra of the micro-organism;
- various design and operational factors affecting the UV dose affecting the micro-organism. If UV-C rays cannot reach the pathogen, it cannot be neutralized.
Reducing the total number of viruses and bacteria decreases the risk of transmission, so the application of UV rays in the disinfection of surfaces and air can be an effective secondary barrier to cleaning, especially if this happens in hasty conditions.