“If supplies are limited, it is possible to reuse filters until they become visibly soiled, moist, or have lost shape,” Dr. Devine said.
However, this isn’t ideal as you can’t be certain what kind of germs might be buried in the filter while you’re wearing it. To ensure you never get caught without the necessary protection, you should always have at least one extra filter on hand at all times, as well as a spare mask. Also, Dr. Devine pointed out that if you’re experiencing any trouble breathing while wearing a filtered mask, you should change the filter promptly.
For a little bit of added protection against COVID-19, many people have begun adding filters to fabric face masks. In fact, many of the cloth masks available from small businesses and major retailers now include a filter pocket specifically for that purpose.
While the CDC’s face mask guidelines don’t discuss filters at length, doctors have suggested that adding a filter to your mask can help keep you and those around you safer.
We spoke with Daniel Devine, MD, a dual-board certified internist and geriatrician and co-founder of Devine Concierge Medicine, to find out more about using filters in masks, and specifically, how often you should change them.
“Masks are coming to market with interchangeable filters, and filters offer the benefit of increased rates of filtration against smaller virus particles,” Dr. Devine told POPSUGAR. You can also use everyday items like coffee filters to make your own filters at home, then simply tuck them between layers of fabric. But just as it’s recommended that you wash your face mask every time you wear it, you should also change the filter every day.