Is microwaving a face mask in plastic baggies a good way to kill COVID-19 particles on the mask? No, it is not. Research shows that hydrogen peroxide will kill the virus on masks, but no proof has been found that microwaving kills the novel coronavirus. Moreover, microwaving can melt the plastic bag and burn the fabric.
The claim that microwaving will kill the deadly virus comes from an article (archived here)] where it was published by SmartAir.com on March 30, 2020, under the title "Does Microwaving Masks Disinfect Viruses?" The story read, in part:
The researchers in Germany tested the effects of microwaving on Hepatitis C and HIV viruses, not coronaviruses. Although there isn't research on microwaving Covid-19, scientists have tested this with human parainfluenza, an RNA virus similar to the coronavirus that infects humans."
Users on social media saw posts like this:
By contrast, another user posted a shot of a mask after trying the "microwave trick":
The microwave rumor has been around for over a week and was debunked by The Washington Post on March 30.
The Post article quotes Benjamin Neuman, chair of Biological Sciences at Texas A&M University, who said:
Even if microwaving the virus kills it, which scientists haven't verified, there's still risk in microwaving anything other than food."
The Post story further warns:
Other medical experts warn against placing the N95 mask into a microwave oven because the mask contains a metal strip across the top that the wearer is supposed to use to form a seal around the top of the nose. There also is a plastic box that holds the filter that will melt. In addition, the materials in other kinds of masks could be damaged by the heat of the microwave, rendering them ineffective.
What has been shown to work better is hydrogen peroxide.
Researchers at UCLA report that an N95 mask sterilized with hydrogen peroxide blocked infectious particles as effectively as a new mask.
Also, Duke University researchers confirmed a way to use vaporized hydrogen peroxide to decontaminate masks so they are safe to reuse. Duke routinely uses hydrogen peroxide gas to sterilize equipment and even entire rooms. The process, tested and published by others in 2016, kills germs on the masks after they're worn.
Matthew Stiegel, director of Duke's Occupational and Environmental Safety Office, said:
We had never considered needing it for something like face masks. But we've now proven that it works and will begin using the technology immediately in all three Duke Health Hospitals."