Raleigh, North Carolina – The Centers for Disease Control and Prevention say you should double down on wearing masks.
Researchers at the University of North Carolina put that idea to the test, running tests to see how much additional protection, if any, double-masking would provide. On Friday morning, they released their findings.
In a briefing, they shared their research on the effectiveness of masks in general, the importance of mask fit, and the additional benefits of double masking.
Fit is the most important
“You really need to address the fit and make sure everything you’re wearing is snug to your face,” said Dr. Phillip Clapp, assistant professor in the Department of Pediatrics.
According to Clapp, simply making sure a single mask is worn can increase effectiveness by 20%.
A mask that is not in place allows air and aerosols to pass through the spaces, decreasing protection against COVID.
Double masking provides greater protection
Testing indicated that double masking provides greater protection, provided the masks are worn.
“With double masking, we see a 15% increase [in protection]simply through a double-masking procedure or surgical masks, “Clapp said.
Additionally, the double mask can provide additional protection, depending on how the wearer puts on their masks.
For example, placing a cloth mask over a surgical mask showed an increase of approximately 40% in efficiency. However, placing a surgical mask over a cloth mask did not provide similar protection.
Mask frames, which help ensure a good snug fit, also provide additional benefits.
However, even the double mask does not compare to wearing an N-95 mask.
But the use of two surgical masks and the addition of a frame or brace around the face to prevent leakage and create a good fit, was 97% effective in one test.
In short, the extra layers provide extra protection, but it’s very important to make sure your mask fits, or else the leak will allow the sprays to pass through.
Finally, Dr. Emily Sickbert-Bennett, director of infection prevention at UNC, addressed the most important type of “double-masking.”
“The most important ‘double-masking’ is when you and the person you’re wearing a mask with,” he said.
So whether or not you decide to wear a double mask, one of the most effective ways to prevent the spread of COVID is simply for everyone to wear at least one mask.
Is it dangerous to wear a mask or a ‘double mask’?
Some people have expressed concern about whether wearing a mask could lower their oxygen levels. So could double masking have a possible downside?
Clapp and Sickbert-Bennett said they don’t think this is a concern.
Clapp said that what people worry about is breathing their own air again, which increases carbon dioxide and decreases oxygen.
However, he said, those concerns are not supported by the science of how masks work.
“When you are wearing a mask, the volume of air inside this breathing space is very low. So when I breathe, I am taking in air from outside,” he said.
That’s the whole purpose of the masks, he explained. They are intended to filter particles from the outside air by breathing air through the masks.
“So you are bringing in fresh air in addition to the small amount of air that you exhaled earlier,” he said.
Sickbert-Bennett said: “Of all our medical colleagues who have reported on this, that’s not going to be a concern.”
When can we stop wearing masks?
Since COVID is transmitted by respiratory droplets, masks are key to preventing the spread.
“If everyone wears masks consistently, I think that’s the best way to end the pandemic,” Sickbert-Bennett said.
She said that when streaming slows down, the community can reevaluate when it’s time to hang up our masks forever.
Until then, we can increase our protection by making sure our masks are on and, if we wish, by double masking.