AIR DISINFECTION TO FIGHT CORONAVIRUS SARS-COV-2
UV-C and Coronavirus
AIR DISINFECTION FAQ
Air disinfection to fight Coronavirus Sars-Cov-2
9 ] Why is air disinfection useful to fight Coronavirus Sars-Cov-2?
Indoor air quality is a very important value, in fact most of the inhabitants of the planet spend most of their days locked indoors, without access to good, clean, healthy air sources.
Air plays a significant role in the transmission of disease. Sars-Cov-2 has been tested by scientists in the virology laboratory of the National Institute of Allergy and Infectious Diseases: the American Institute for Infectious Diseases.
The results were published on March 17 in the scientific journal New England Journal of Medicine.
Sprayed with aerosols under laboratory conditions, the coronavirus survives up to three hours. In the period between the time of nebulization and the end of the three hours, its quantity was significantly reduced (halved within an hour). Survival remains, however, higher than we would like.
It should be ponted out, however, that transmission always takes place between person and person, and not directly through the air. What is called “social distance” is the only good practice to avoid contagion. It has to be considered, however, that in a closed environment with limited air circulation, the breaths and “droplets” emitted by people sneezing, coughing and talking can concentrate at levels that make the presence of more people risky in case of infection. The sharing of common enclosed spaces should therefore be avoided as much as possible unless there are systems that “dilute” the concentration of the microbial load or frequent air changes are foreseen.
10 ] How can we disinfect the air?
To reduce disease transmission, air can be disinfected in three ways:
- Ultraviolet germicidal irradiation (UVGI) or UV-C purification
These approaches are applicable for the control of any pathogen from colds, flu, to measles and even bioterrorist agents.
11 ] What is meant by Dilution, Filtration and Air Purification?
Dilution reduces the concentration of infectious agents by increasing the amount of external air flow into the occupied space. Dilution does not destroy microbes, but rather reduces their concentration by spreading them over a larger volume of air.
Filtration reduces the concentration of infectious agents by passing air through high-efficiency air filters that trap bacteria and viruses and remove them from circulation.
UV lamps can be used in closed spaces by placing them in ventilation ducts in AC, or applying specific systems for the treatment of the “upper” air layers in environments higher than 2 mt and 50. Stand-alone air purifiers are also another way of treating air in closed environments. The use of UV-C lamps is recommended in all spaces shared by several people. Infectious particles move in the air following natural convective motions, which typically move from the bottom to the ceiling of a room. Complete microbial inactivation occurs due to the cumulative effect of exposure over time, as infectious particles are repeatedly transported in recirculation. Each UV-C passage inactivates the infectious particles until their concentration is effectively eliminated.