ARI SHAPIRO, HOST:
As coronavirus cases surge in many parts of the U.S., health officials and lawmakers on both sides of the aisle are urging Americans to wear face masks in public. To answer some common questions about the safety of wearing masks, especially for long periods of time, NPR health correspondent Maria Godoy joins us now.
MARIA GODOY, BYLINE: Hi, Ari.
SHAPIRO: Masks stop the spread of the coronavirus. We know that. That's important. We want to reiterate that. At the same time, I've seen people express concerns. One common one is, like, people are worried that wearing a mask might limit oxygen intake in ways that could be harmful. Is that anything people should actually be concerned about?
GODOY: You know, no, not for the types of cloth masks or surgical masks that the general public wears. The fibers they're made of aren't dense enough to block the exchange of gases, like oxygen or carbon dioxide. And these masks aren't so tight that air can't get in around the sides. Now, there is some evidence that wearing N95 respirators for long periods of time - like an hour or more - can reduce the amount of oxygen you take in, but those masks seal more tightly to the face. And the risk there is really for people who are predisposed to breathing problems, like emphysema. So, you know, and also really only medical workers should be wearing N95s because they're still in short supply.
SHAPIRO: You mentioned people with emphysema. What about people who have serious respiratory conditions? Is the masks calculation different for them?
GODOY: You know, actually, doctors say people with these conditions especially need to be masking up in public because they are at greater risk for severe disease if they get COVID-19. Even if someone, you know, relies on oxygen when they go out in public, they can wear a loose-fitting mask over their cannula, which is that tube that delivers air under their nose. And if someone with a serious respiratory condition is having a really hard time breathing through face mask, they should definitely talk to their doctor, but they could try a face shield. These are plastic shields that attach to the top of your head, and they go down past your chin, and they wrap around your ears. And they can block incoming respiratory droplets, though it's not yet known how well they protect other people from the wearer.
SHAPIRO: What about exercising with a mask? You're breathing heavily. You're sweating. The mask sticks to your face. What's your advice there?
GODOY: You know, that is a legitimate concern. If you're doing something like running or biking outdoors and you're alone or just with the people you live with, it's OK to pull down your mask as long as you haven't been touching stuff along the way, like benches or rails. If you see someone coming, pull up your mask until they pass. Indoor gyms are tricky because we know people who breathe heavily are likely to expel more respiratory droplets, and they aren't going to disperse as quickly as they would outdoors. So you really have to weigh the risk for yourself there.
SHAPIRO: And let me ask about comfort because people who are required to wear a mask at work all day say that after hours it can become really uncomfortable. What advice do you have there?
GODOY: You know, experts say it's OK to take periodic breaks from wearing a mask. Just make sure you do it when no one's around. Maybe, you know, step outside first. And also try out different masks to see what's more comfortable for you because a mask is only useful if you actually wear it.
SHAPIRO: You mentioned that you can take it on and off. We've also been told we're not supposed to touch our mask when we wear it, so how do you reconcile that?
GODOY: You know, don't touch the front of the mask when you take it off so you don't touch any infectious droplets it might have blocked. And instead, you take it off by the earlobes. And you wouldn't want to touch your mask if you're indoors, like in a store, where your fingers might have touched, you know, objects that have virus droplets from other shoppers. But if you're outdoors and solo and you haven't been touching stuff along the way, you haven't had a close chat with someone, it's OK to pull down your mask to catch a breath. You know, as one doctor told me, nobody is 100% perfect with this. Just do your best.
SHAPIRO: That is NPR health correspondent Maria Godoy with the latest information on masks.
GODOY: Thanks, Ari.
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