First, it was toilet paper and bleach.
Will air purifiers be the next target of a pandemic-fueled, clear-the-shelves shopping spree?
Only time will tell, but people are now looking at air purifiers, also called air cleaners, to help them reduce the risk of contracting COVID-19.
It makes sense, as the disease is caused by an airborne virus. In a closed environment, that virus may travel farther than a 6-foot social distancing limit, according to updated guidance by the Centers for Disease Control and Prevention (CDC).
The virus also could linger for some time after an infected person has left the room. “In these instances, transmission occurred in poorly ventilated and enclosed spaces that often involved activities that caused heavier breathing, like singing or exercise. Such environments and activities may contribute to the buildup of virus-carrying particles,” reported the CDC.
Hence, a home-use purifier is looking more and more like a smart purchase — especially with winter coming, when people tightly close their windows and doors to keep out cold air and keep in the warmth.
What air purifiers do and don’t do
The Environmental Protection Agency said that Americans spend about 90% of their time indoors, where air quality may not be healthy. Concentrations of some pollutants, such as particulate matter (solid particles and liquid droplets in the air), smoke, pesticides and even animal dander are typically 2 to 5 times higher indoors than outdoors. Air purifiers help filter out these unwanted particles and more from the air.
And now we can add COVID-19 to the list.
Air purifiers are not a one-step solution in any air-cleaning situation, and they don’t guarantee that your air will be 100% virus-free. But they can reduce the amount of virus in the air.
“The more air exchanges and the cleaner the air, the lower the risk,” infectious disease physician Gregory A. Poland, MD, said in an article in the Mayo Clinic News Network. “Let’s be sure the air in our home, if we’re having people to our home, is as safe as it can be. That means a HEPA [high-efficiency particulate air] filter.”
In a recently published NPR article, Joseph G. Allen, DSc, an associate professor of exposure assessment science at the Harvard T.H. Chan School of Public Health, said that air purifiers were a simple “plug and play solution,” and a relatively easy way to circulate clean air. Dr. Allen also directs the school’s Healthy Buildings program.
Using an air purifier is just one layer of protection though. Even if you use a purifier, you still have to continue with prevention measures: wearing masks around people you don’t live with, staying 6 feet apart when possible, and frequent, thorough handwashing.
The good news, according to Dr. Poland, is you don’t have to spend lots of money to get a fairly efficient purifier. A portable cleaner that you can move from room to room, with a quality high-efficiency particulate air filter, will do the trick. “The filter does not kill the virus, but rather it exchanges clean air more rapidly to get rid of the virus,” he said.
But how do you know if the air cleaner or purifier you purchase will do any good? And how do you ensure it works as well as it should?
Richard Corsi, PhD, dean of the Maseeh College of Engineering and Computer Science at Portland State University in Oregon, told NPR that consumers should “[l]ook for a unit with a HEPA filter and a clean air delivery rate, or CADR, of 300 cubic feet per minute [not hour] or better — and not much else.” In other words, the average consumer seeking to clear the air of potential virus contamination doesn’t need extra bells and whistles.
The HEPA filter is important, too, said Dr. Poland. “With a HEPA filter, [the virus] is being attached electrostatically to the filter itself so that it cannot then circulate in the air, which is why changing the filters and changing them properly is so important.”
Be sure to buy the right size air purifier. If you buy one that is too small for your room, it won’t do the job. If you buy one that’s too big, you may have spent more money than necessary. There are various air purifier sites online that tell you how to calculate the size you should consider.
For an air purifier to do its job, it must be located properly to ensure that the vent blows air away from people, not toward them. Follow the manufacturer’s recommendation about where to place it in the room.