Are All Masks Created Equal? How To Find The Right Mask To Protect Against COVID-19
SCOTT SIMON, HOST:
Public health officials have been reminding Americans for months how vital it is to wear masks or some other face covering during this pandemic. We've been told they reduce the spread of the coronavirus. But as it is written, all face coverings are not created equal. This week, there was confusion over reports that a certain kind known as the neck gaiter could actually encourage the spread of the coronavirus. NPR's science correspondent Richard Harris joins us now to talk about - can we call it gaiter-gate, Richard?
RICHARD HARRIS, BYLINE: That's a great idea, Scott. Let's do that.
SIMON: All right. Well, tell us the story of this controversial face covering. They're made of thinner fabrics, and they seem to be especially popular with runners, right?
HARRIS: Right. The story is about a fabric tube that you wear around your neck and you can pull up to cover your mouth and nose. And the misunderstanding about this is from a paper published in the journal Science Advances by a team at Duke University. A doctor there wanted to give away masks, but he was hoping to figure out which ones worked best. So he sent a bunch of different products down to the physics department. There, Professor Martin Fischer and a team, including his undergraduate daughter, Emma, as a matter of fact, set out to devise a way to see how effective masks were at blocking respiratory droplets.
MARTIN FISCHER: The aim of the study was never to do a systematic study of all mask types and mask materials. Masks vary all over the place.
HARRIS: He just wanted to develop a testing technique that he could share. And in the process of doing that, Fischer ran 14 different masks through this process just to see how well the system he devised would work. A volunteer would say, stay healthy, people, five times into a device involving a laser, a smartphone and some duct tape. N95 respirator masks did fine. And most layered cotton masks he tested were also pretty efficient.
SIMON: When did this routine lab study become a controversy?
HARRIS: Well, Scott, it turns out that one of the face coverings in the pile that was to be tested was a - this gaiter, or the neck tube - whatever you want to call it.
FISCHER: The one that we tested was a 92% polyester, 8% spandex blend. It was single layer. You can stretch it out and you look at - look at it through - hold it against the sun, and you could see light going through it. And you could easily blow through it.
HARRIS: And the test involved a single test by a single volunteer - hardly what you'd call a rigorous study of this garment in particular, or certainly neck gaiters in general. But some reporter picked up on this finding and decided to write a story focusing on this single outcome and saying that neck gaiters essentially don't work as face coverings.
SIMON: Richard, I've always thought neck gaiters make somebody look like, you know, they're a Teenage Mutant Ninja Turtle. But other than that, can they be effective in this pandemic?
HARRIS: Well, we can't really say much. In general, we know that materials you can see through and can easily blow through aren't likely to be as effective as denser material when it comes to mask material. But, you know, of course, the denser the material is, the harder it is to breathe through. So everybody would like to find that sweet spot where it's not too hard to breathe but the face covering is still blocking particles.
SIMON: What about those masks that look so official with the vents that help you breathe out?
HARRIS: Not a good idea. The single sample in this very limited experiment didn't do too badly, but the CDC advises people not to use them. Let's remember they're designed to protect the person who's wearing them from inhaling bad stuff, not exhaling bad things like, say, a virus, and that defeats the purpose of wearing a mask to control the spread of the coronavirus.
Let's remember the main reason that health officials are telling us to wear masks is many people who have the coronavirus don't know it, so we're mostly protecting people around us when we wear a mask. I will say there is also some evidence that they protect the wearer as well, but I would say don't count on that.
SIMON: NPR science correspondent Richard Harris, thanks so much for going into all this.
HARRIS: Happy to be with you, Scott. Transcript provided by NPR, Copyright NPR.