WASHINGTON — Double masking and wearing a more fitted mask – they’re part of the CDC’s updated guidance for reducing transmission of the coronavirus and its variants.
Every week the CDC issues a morbidity and mortality report, but his week’s report has brought on a deluge of questions. One of the most popular is about whether or not double masking will reduced oxygen intake and reduce the ability of carbon dioxide to escape the thicker masks.
WUSA9'S Ariane Datil spoke to Dr. Monica Gandhi, one of the scientists whose research was used by the CDC in issuing this new guidance.
"I understand that concern but it’s actually been examined," Dr. Gandhi, an infectious disease doctor with the University of California San Francisco, said. "This has been scientifically looked at and there's no drop in oxygen nor an increase in carbon dioxide."
Dr. Gandhi said oxygen and carbon dioxide are such tiny molecules that they can easily pass through a double-layered mask. She co-wrote a commentary with Virginia Tech engineering professor Dr. Linsey Marr that spurred the CDC’s updated guidance.
"So the research was... to use different combinations of masks and different types of masks on a mannequin," she said. "Then she kind of sprays it with different sized particles to see if it blocks the virus more."
Their research found that N95 masks are most effective, but they also learned that placing a cotton mask on top of a surgical mask could reduce a wearer’s exposure by about 90%. Those results simulate the efficacy and filtration of an N95 mask.
Double masking isn't the only option Dr. Gandhi said.
"One is doing two layers of cloth with the filter inside, which is thinner," she said.
During a news conference, D.C. Health Director LeQuandra Nesbitt addressed the CDC’s weekly report.
"What they emphasize in that report is that people should wear masks that fit properly," Dr. Nesbitt explained. Adding that for some people "putting a cloth mask on top of a medical procedural mask ensures a better fit."
If you’re planning to double mask, the CDC’s new research indicates it's best to fit the surgical mask closer to your face by knotting the corners and tucking in the excess fabric.
So do you need to double mask while you’re outside?
Dr. Gandhi says no.
"The recommendation is not actually to do this outside because you have that ventilation going for you," she confirmed. "It's actually inside to up our mask game, and do that now with all these transmissions. But not outside."
If you’re not a fan of double masking, Dr. Gandhi notes that even with an N95 respirator mask a good fit is essential.