MADISON, Wis. - The United States Centers for Disease Control says two masks are better than one when it comes to slowing the spread of the coronavirus. The key is to get a good fit. The CDC cited University of Wisconsin research and creation as an alternative to wearing two masks.
In the photo below, you can see a simulated breath going up and out of a disposable mask. University of Wisconsin engineers went to work to try to fix that.
UW Engineering experiment
"It’s a rare opportunity, I think, for mechanically engineers to contribute to a public health problem," said Scott Sanders, UW professor of mechanical engineering.
In 2020, the university asked Sanders and a colleague, David Rothamer, to look at how to make classrooms safer. It led UW engineers to create the "Badger Seal," something you can buy or make at home.
Sanders explained what it takes: an ordinary disposable mask, a garden tie used for tomato plants, elastic, and VELCRO.
CDC guidance cites their work. The document says the goal is to get a good fit, which can include double masks or a mask fitter, like the Badger Seal.
"Masks work, and they work best when they have a good fit and are worn correctly," said Dr. Rochelle Walensky, CDC director.
The CDC says a mask fitter "can potentially increase the wearer’s protection by ≥90%."
"I hope that to the degree there is a demand, I hope it can be met because this is saving lives," said Sanders.
While the CDC touted the mask fitter, the Badger Seal team still puts up a disclaimer that the FDA has not approved it for medical use.
In the same document referencing the UW research, the CDC encouraged the option of wearing two masks. The CDC found one mask blocked around 40% of the particles going to another person. When a cloth mask was worn on top of a surgical mask, about 80% were blocked. When both people were double-masked, that number rose to more than 95%.
You can buy a Badger Seal, or make your own at home.