Can HEPA Air Purifiers Help Reduce COVID-19 Spread?

The short answer is YES!

We know that HEPA filters, according to NASA, are nearly 100% effective at capturing nanoparticles such as viruses (like the Coronavirus) and bacteria, because of Brownian Motion, but does that translate to reducing the spread of Covid in a room full of people?

Center for Disease Control (CDC) studies show that the answer is YES! Air purification is another essential tool in our protection against Covid and other viruses, along with vaccines, masking, social distancing, etc. Air purifiers do, in fact, reduce the spread of Coronavirus and its variants. 

Georgia School Study Shows Classrooms with HEPA Air Purifiers reduced the spread of Covid by 41%!

A CDC study in Georgia Elementary Schools compared the effectiveness of prevention strategies in schools for reducing the spread of Covid. They collected data on ventilation and air purification in schools where the community Covid rates were similar, to determine what was most effective and whether air purification and ventilation reduced the spread of Covid. 

123 elementary schools participated, and findings were that in schools where air purification alone was used, Covid transmission was reduced by 41%. Schools that used air purifiers with HEPA filters saw a 41% decrease in Covid cases compared with schools who did nothing.

Adding increased ventilation to the use of air purifiers added another 7% reduction, for a total reduced transmission rate of 48%!  Air purification is an essential tool in reducing the spread of Covid and other viruses in schools and workplaces.

CDC Study shows up to 65% reduction in exposure to viruses

with the use of HEPA Air purifiers!

A CDC study on the efficacy of air purifiers showed up to a 65% reduction in exposure to SARS-CoV-2 (the virus that causes Covid) in a simulation with an infected participant in a meeting with a speaker and other participants. They tested the HEPA filters at different locations in the room as well as at different elevations using simulated aerosols from the infected participant and tested the exposure to the other participants in the room. Optimally placed HEPA air purifiers reduced the exposure from an infected source to the others in the room by 65%!

The combination of HEPA air purifiers and universal masking reduced exposure to the virus by 90%. Using HEPA air purifiers is highly recommended, along with masking, to reduce the risk of exposure to the SARS-CoV-2 virus to protect from Covid.

Studies show that ventilation and purification make a big difference in reducing Covid, and that Air Changes per Hour (ACH) is an effective way to measure that. ACH is the number of times the air in the room passes through the purifier and is cleaned in an hour.[1]

The more air changes per hour, the more frequently the air in the room is filtered and cleaned.  ASHRAE recommends 4-6 ACH in a busy setting like a classroom. Smart Health air purifiers are cost-effective, high powered, quiet purifiers that will give you the air changes per hour that you need to reduce your risk to Covid and other viruses, bacteria, allergens, pollutants, etc., and help you breathe better.

At Smarter HEPA we are passionate about bringing cleaner and safer air to you. We believe that air purification is an effective and essential tool in the fight against viruses like flu, Covid and its variants (Delta, Omicron), along with other recommended safety protocols like vaccinations, masking, handwashing, and social distancing.  


[1] The ACH number is calculated by taking an air purifier’s filtering capacity in cubic feet per minute (CFM) times 60 minutes/hour and dividing that number by the volume of the room. Volume is the area of the room in square feet times the height (generally calculated at eight feet).  CFM x 60 / Length x Width x Height (8ft)

Written by Sonja Palmer

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