Use Air Cleaning as Part of Your Strategy Against Covid in the Home

Inching closer to the start of the third year of Covid-19 in the United States, homeowners understandably continue to be concerned about risks of transmission within their own houses, especially if they have frequent guests. Fortunately, a variety of effective tactics, taken in tandem, can minimize the risk of infection in your home.

One of these tactics is the proper use of air cleaners/purifiers and HVAC filters in a residential setting. To varying degrees, these can reduce the incidence of a wide range of airborne contaminants, including the virus that causes Covid-19. But they’re most effective when used as part of a broader strategy that includes masks and social distancing around unvaccinated people or those whose vaccination status is unclear, as well as effective ventilation in the home,

How to Select an Effective Air Cleaner

Simply put, HVAC filters and air cleaners, if performing as designed, will remove pollutants/contaminants from any air that passes through them. These devices come with a range of ratings meant to tell you how effective they work against smaller and smaller airborne particulates. Viruses such as SARS-CoV-2 are comparatively small, which means lower-efficiency filtration won’t remove particles carrying them from the air. Air purifiers/cleaners especially come in handy in situations where it’s too cold or humid outside to depend on natural ventilation to cleanse indoor air. The same goes for situations where outdoor air pollution is present.

The most common type of air purifiers, cleaners and HEPA filtration devices are portable models intended for use in limited areas, such as a room or small level of a home. They’re relatively inexpensive, though the prices generally rise with their effectiveness at filtering out more and smaller particulates, and their capacity in terms of square footage.

Will the Purifier Remove Viruses?

According to the federal Environmental Protection Agency (EPA), for an air cleaner/purifier to filter viruses from the air, it should have the ability to remove airborne particles as small as 0.1 to 1.0 microns. In other words, very, very small. Most of these devices cannot remove particulates that are that small, perhaps only going down to 3 microns.

It’s a good idea to become conversant with the various ways that manufacturers state the efficiency of air cleaners and purifiers. One common method is to claim that a particular filtration device will remove a certain high percentage (e.g., 99 percent) of particles as small as, say, 2 microns. Some manufacturers reference the CADR rating system (i.e., Clean Air Delivery Rate) for how well an air cleaner performs. Manufacturers can be expected to mention what sort of technology they use to remove airborne particulates, such as HEPA filtration or UV light. The best air purifiers use more than one technology to do their job.

When selecting the system that’s best for your home, pay attention to whether it’s the right size and capacity for the space you want to purify. The device description usually will state what maximum square footage it should be used for. It’s also important that the air cleaner has a sufficiently high CADR for smoke (as opposed to dust or pollen), and/or has the ability to filter airborne particulates ranging from the aforementioned 0.1 to 1.0 microns (sometimes expressed as “um”).

Portable or Whole House?

As mentioned, standard air cleaners or purifiers are meant for limited areas, a room or relatively small section of a home or apartment. Some high-efficiency air filters also can be installed in the central forced-air heating and cooling system, though ultra-efficiency filters such as those using HEPA technology may require modifications to the HVAC equipment. Otherwise, they risk slowing airflow through the system due to their dense filtration media. That’s something to be avoided for a variety of reasons, including efficiency and performance. Whole-house air purification systems also can be installed to work in tandem with the home’s forced-air system, using varied technology.

Take a Multi-Faceted Approach to Preventing Covid

It’s important to repeat, if your goal is to minimize the risk of infection and transmission of the virus that causes Covid, you should not rely on just one strategy, whether air purification, ventilation or safe practices such as masks, distancing, hand-washing and the screening of guests. Use “all of the above” for the safest approach to warding off viral infection in your home.