On April 3, 2020, the Centers for Disease Control and Prevention (CDC) issued a new recommendation to help prevent the spread of COVID-19 coronavirus disease: People should wear cloth or fabric face masks when they go grocery shopping, visit pharmacies, or do other essential errands. Made from T-shirts or bandanas, these face coverings are an at-home alternative to surgical masks or N-95 respirators, which the CDC recommended only for healthcare workers on the front lines of the pandemic.
The recommendation — which the CDC posted in a statement on its website alongside a 45-second video of U.S. Surgeon General Jerome Adams demonstrating how to make one of the cloth masks — spurred a wave of do-it-yourself guides online.
But this raised a new dilemma among crafty Americans making their own masks: How should people clean the masks in order to safely reuse them? Making a new face guard for each trip outside could prove tedious.
Cue the advice of Facebook: "Those that use a fabric mask - after wearing place in ziplock bag and microwave 2-3 minutes to sanitize. Do this after each wear," says a post that users have shared more than 7,200 times. Another post with similar advice has about five times that amount of shares.
People contacted Snopes seeking clarity.
According to an April 9 instructional guide by the CDC, people who go outside wearing fabric or cloth masks should clean them regularly, the frequency of which depends on how often the face coverings are used. When asked by Snopes if microwaving cloth masks will sanitize them, a CDC spokesperson responded via email with a bulleted list of what cloth face coverings should do, including "fit snugly but comfortably against the side of the face" and "be able to be laundered and machine dried without damage or change to shape." The latter bullet point was highlighted yellow in the email.
In other words, the CDC has not explicitly forbidden the public from microwaving the face coverings nor weighed in on the effectiveness of the method. But it has made this recommendation, including in its April 9 guide: "A washing machine should suffice in properly washing a face covering."
Meanwhile, Greeneville/Greene County Office of Emergency Management and Homeland Security on Facebook warned against microwaving face masks, writing on Facebook:
There are a couple of problems with this:
1. The microwave will set flame and/or burn certain materials.
2. If your mask has metal in it, refer to issue number 1, as well as, possibly killing your microwave.
Please do NOT microwave your hand made masks.
Washing in warm water and Antibacterial Soap and a small amount of bleach will disinfect your masks of any germs. Yes this includes COVID-19.
"DO NOT place any face mask in the microwave for any amount of time," the Colorado River Fire Rescue department also said on Facebook. "There is no evidence that microwaving a face mask will sanitize it properly."
Proof of people’s failed attempts at the microwave idea are available via social media, too. People have shared stories of kitchen fires starting in their microwave and photos of charred fabric masks. "I tried it," one Facebook user wrote. "Please don't try it. It smells awful."