Life Kit - What to know about wearing a mask on public transit

Episode Date: April 23, 2022

Now that a federal judge has thrown out mask mandates on public transportation, many people are wondering, "How safe is it to use these forms of travel if many people aren't masked?" In this episode Life Kit, learn how to assess your risk and make the best choice for you.Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy

This is NPR's Life Kit. Planes, buses, rideshares. A federal judge has ruled we can now take masks off on public transit. But your worries about safety might still be on. Will I still be protected if I continue to mask, even if no one else is masked? Are some types of transportation safer than others? How do I deal with mask judgment? I'm Andi Tagel, one of the producers of this show.

And in this episode of Life Kit, NPR health correspondent Maria Godoy is here to answer your questions and help navigate us through these new mask-optional roadways. Maria, thanks for being here. Always a pleasure to get a little time with you. Thanks, Andi. Okay, to start, a lot of people might not feel comfortable with taking their masks off just yet, but are we even still protected if we choose to mask in public spaces where other people aren't masked? Look, a high quality mask like an N95 will offer really solid protection. It's not foolproof because nothing is, but it's really, really good. And experts agree that you are at less risk wearing an N95

than not, but a lot of people don't want a mask forever. So it helps to understand that different situations pose different risks, so you can decide for yourself. Very good to know. Okay, so let's talk about some of those different situations. There's obviously several types of transportation we all use. Are they really that much different from each other when it comes to the risk of getting infected? Yes, because it's all about the air we share with others and how it circulates. And that can be quite different depending on the mode of transportation. Right. Okay. What should we start with? Airplanes. Because people are so jam-packed together, right? Well, yeah, it's counterintuitive because you are in a small enclosed space. But the good news is that every researcher I've spoken with agrees that the air

filtration and ventilation on an airplane is really about the best it can be for an indoor environment. The air gets exchanged every few minutes in an airplane cabin, like in a Boeing 767. Joshua Santarpia is a microbiologist at the University of Nebraska Medical Center who has sampled the air during flights. He says the tiny respiratory particles that can carry the virus get sucked away quickly. Your exposure level to people, even in your immediate area, by aerosols alone, is not particularly high. Lindsay Marr studies airborne virus transmission at Virginia Tech, and she says there is a caveat to that if you happen to be sitting close to someone who is infectious and unmasked. There's still a risk, though, of transmission with those immediately

nearby, like next to or the row in front or row behind. Or if you're standing in the aisle waiting for the bathroom. Mar says even if other people aren't wearing a mask, she's got to keep wearing an N95 on flights for now because those masks really do protect the wearer. You also have to consider the risks of infection among crowds of travelers or while you're hauling luggage and you're, you know, jostling for it in each other's faces. And also, even once you're on board, several experts told us that sometimes the airlines don't keep the ventilation systems on fully while you're on the ground. Although we should note that Boeing's guidance to airlines is to keep its airflow system turned on with HEPA filters and circulating at all times that passengers are on board.

Okay. We've talked about planes. What's next? Trains and buses. Mar says the data she's seen from the subway systems in New York City and San Francisco show they have good air ventilation. And if she were on a subway car with, you know, fewer than 10 people on it, she probably would go without a mask. But if you're standing shoulder to shoulder with other riders, that ventilation alone won't be enough. And as for buses, the situation there is more concerning. Jesse Capasolatro of the University of Michigan has researched how air flows on urban buses. What we found was if the windows are closed due to sort of the recirculation of the air in the bus, whatever someone breathes out in about 45 seconds, everyone in the bus is breathing in a portion of that.

Wow. That's a strong mental image. 45 seconds. That's all it takes. Yeah. To share air on a bus. Now opening windows can make a big difference, but you can't always do that on buses. Now it's worth noting that a typical city bus is going to, you know, bring in fresh air more frequently than say a typical building, which is good news. Although other experts I've

spoken with note that bus is also a smaller space that tends to be more crowded. So that's another factor to think about. I also spoke with Neil Siegel. He's a health policy researcher at the University of Maryland, and he says the fact that ventilation tends to be bad on buses raises real equity concerns. Hispanic and Black people are more than twice as likely to take public transit than white people. And people with lower incomes are also disproportionately more likely to take public transit than people with higher incomes. Siegel says the end of mass mandates on buses means that people with fewer options for safer travel are now facing increased risk. Yeah, that's really important to remember that this isn't going to impact everyone equally. Right. Along those lines, a lot of people take ride shares. A lot of people

are ride share drivers. What do we need to know there? Okay, so if you've ever been in a passenger car with a smoker, you know that the cabin will quickly fill up with smoke when the windows are up. Some people actually call this hotboxing with cigarettes and, you know, other substances. But infectious aerosols behave like smoke. So in an enclosed car, they're also going to build up quickly. So if you're in a cab or say a ride sharing vehicle, open the windows all the way to lower your risk of transmission. If you're cruising along at a good clip, opening the windows fully is best, but even partially open windows can help a lot. If you're cruising along at a good clip, opening the windows fully is best, but even partially open windows can help a lot. If you're stuck in traffic, research suggests you also want to open all the windows, but run the AC too at full blast if you can. You know, there's studies showing that this can help clear out those aerosols.

Get the air moving. No one wants to be hotboxing infectious aerosols. Yeah. Okay, now this is a big change for everyone, but some groups are going to be impacted more than others by this news, right? I'm thinking about families with small kids under five who aren't yet vaccinated. This also really impacts immunocompromised people

of all kinds. How can folks who aren't at higher risk think about their role in keeping other people safe? Yeah, this is something that I personally think a lot about. Even though my own risk of severe disease isn't that high, I do still wear a high quality mask like an N95 in small enclosed public spaces. And that's really because I don't want to put others at risk. And definitely I do it if I have cold like symptoms. I really want to be mindful of others who might be vulnerable because of their age or other health risks. Absolutely.

And on that note, there are lots of different feelings out there about all of this. Yep. And I can respect that. Yeah. And so, you know, not everyone is automatically thinking about the person next to them. I anticipate some mask side-eyeing might be happening for people who choose to stay masked. Any thoughts on dealing with people who give you a hard time on public transportation or just out in the world? Well, so, you know, I'm going to admit that once or twice I have gotten dirty look masking while others weren't. And I just sort of

kind of fake cough like behind my mask, just like a reminder, hey, I'm protecting you. But actually, one time I was taking a walk and a person sort of like yelled at me because I was wearing a mask outdoors, which, you know, risk of transmission is very minimal. This was earlier in the pandemic. But actually, I was wearing a mask because I was feeling really cruddy and I had taken a PCR test and I was waiting for the results. Yikes. So you're trying to be considerate of your neighbors and you got yelled at for it. That's a good reminder. You never know what someone else's situation is,

so we shouldn't assume. Right. But hopefully this episode can help curb some of that. So thanks so much for all this great info, Maria. All good things to keep in mind. Oh yeah, my pleasure, Andy. For more Life Kit, check out our other episodes. We've got one on how to start biking to work,

another on maintaining long-distance friendships, and lots more on everything from finance to mental health. You can find those at npr.org slash lifekit. And if you love Life Kit and want more, subscribe to our newsletter at npr.org slash lifekitnewsletter. This episode was produced by Megan Cain, who's also the managing producer, with reporting and editing help by Will Stoneain, who's also the managing producer, with

reporting and editing help by Will Stone. Beth Donovan is the senior editor. Our production team also includes Sylvie Douglas, Audrey Nguyen, and Mansi Khurana. Our digital editor is Dahlia Mortada, and our visuals editor is Beck Harlan. I'm Andi Tegel. Thanks for listening.