Sometimes wearing two masks is better than one. Dr. Anthony Fauci approved the wearing of two masks for a firm and comfortable fit, and the Centers for Disease Control and Prevention (CDC) found that double masking can improve protection by about 50%.
However, a double mask may not be necessary if you already have a well-fitted mask, a recent study found as a research letter in JAMA Internal Medicine.
Researchers at the University of North Carolina at Chapel Hill tested several combinations of masks on volunteers, from a single cloth mask to doubled surgical masks. They found that wearing a full-face mask, such as a bandana or ice, over a surgical mask provided the best filtration.
“[This] it makes us understand that double masking is most effective because of the improved fit it provides, not because of the extra layers, “lead author Emily Sickbert-Bennett wrote in an email to Insider.
The study found that placing a cloth mask over a surgical mask also improved matching and filtering. However, the same combination with the surgical mask above offered no additional benefit compared to wearing a single surgical mask.
Surgical masks filter the particles well, but their fit can be improved
Most surgical masks are made of non-woven layers of polypropylene, the same material used to make top-level N95 respirators. Some are even equipped with an electrostatic barrier designed to catch infectious particles, Insider, air virus expert Linsey Marr, previously said.
But surgical masks may not fit compared to cloth options. The layer of a fabric mask on top combines the top filtering of a surgical mask with an improved fit.
If the double mask sounds awkward, there are other ways to make a surgical mask fit better. In a CDC double-mask study, knotting the ends of a surgical mask and wrapping the fabric so that it wrapped better around the wearer’s face worked almost as well, as did the folding.
Other scientists have suggested using a dental brace to make a single surgical mask adhere better to the face.
Double masking is very effective – if everyone does it
Both the CDC study and recent research at Chapel Hill have found that wearing a mask works best when both interacting people wear well-fitted masks.
“The best form of double masking is when you and the person you’re interacting with have a mask,” said Sickbert-Bennett.
This universal masking approach could achieve a 95% reduction in infectious particles, regardless of the right option that people choose, the CDC study concluded.
This article was originally published by Business Insider.
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