Indoor Air Quality is Cool for Schools : Short Wave The benefits of indoor air quality in schools are substantial, but American school buildings are old and many face major challenges when it comes to upgrades.

Science and health correspondent Maria Godoy talks to host Aaron Scott about how there are a few hopeful signs that indoor air quality in schools will be improved- including some federal money and a new awareness of air quality because of the pandemic.

Read Maria's story on indoor air quality in schools here:

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Indoor Air Quality is Cool for Schools

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Good day, SHORT WAVErs. Aaron Scott here. As we've talked about many times on the show, the COVID pandemic has highlighted just how much the air we breathe matters. And science correspondent Maria Godoy is here to talk to us today about air in a very important type of building.

MARIA GODOY, BYLINE: Hey, Aaron. Welcome to the science desk.

SCOTT: Thank you so much, Maria. It's a joy to get to talk to you.

GODOY: Yeah, likewise. And, you know, you're right. Air quality is really important in schools. I actually want to start this episode by handing the metaphorical mic to Tracy Washington Enger. She says actually, the pandemic has made her job easier.

TRACY WASHINGTON ENGER: You know, it is such a hallelujah moment, absolutely.

SCOTT: A pandemic hallelujah. I will raise my hands up to that. So what is she talking about?

GODOY: (Laughter) So Enger works at the Environmental Protection Agency's Indoor Environments Division. For more than 25 years, she's been fighting to improve the air quality inside of America's schools. She's very deeply passionate about the issue. She says the benefits of better air quality are well-documented and substantial.

WASHINGTON ENGER: One of the things that has been a real mission for us has been to help schools recognize that creating healthy learning environments is really connected to health and academic performance.

GODOY: But, you know, America's schools are really old. There was a 2013 survey that found even back then, the average school building was constructed more than 40 years earlier. A lot of schools face major challenges when it comes to making air upgrades.

SCOTT: Right. And I'm guessing we're talking here about that constant struggle in education where the schools have way more needs than they actually have a budget to cover.

GODOY: Exactly. But today on the show, I want to talk about how there are a few hopeful signs, including some federal money and a new awareness of air quality because of the pandemic.

SCOTT: We are going to get passionate about clean air.

GODOY: Woo-hoo (ph).

SCOTT: You're listening to SHORT WAVE, the daily science podcast from NPR.


SCOTT: All right, Maria. So you're here to talk to us about how getting school districts to focus on indoor air quality has often been difficult because of all the demands that are competing for their limited school budgets - you know, basic things like hiring enough teachers or maintaining some often very old buildings.

GODOY: Yeah. So the EPA's Tracy Enger says often what happens is that school districts will prioritize funds to clean up indoor air only after some kind of emergency.

WASHINGTON ENGER: When they found the mold problem, when their asthma rates were kind of going through the roof, then they started to seek out that kind of help with indoor air quality, and they would find us.

SCOTT: And then came the COVID pandemic, which is an emergency in its own right.

GODOY: Absolutely.

SCOTT: So people started to get concerned that kids needed to go back to school after lockdown, but also, now there's this huge emphasis that the return to school had to be safe. And I'm guessing that started to mean air quality.

GODOY: Right. And, you know, as you know, virus particles can linger in the air indoors and spread COVID. A key to clearing out those infectious particles is good ventilation and air filtration, which means suddenly, finally, lots of people have started to pay attention to indoor air quality. People finally care. Joseph Allen directs Harvard's Healthy Buildings Program. And like Tracy Enger, he says it's about time.

JOSEPH ALLEN: The way we design and operate our buildings has been an afterthought for too long.

GODOY: Even though Allen says the health and academic benefits of good ventilation in schools have been seen repeatedly in different countries and in different ages.

ALLEN: We see benefits in kindergartners. We see benefits in high schoolers. We see benefits in college students and middle schoolers - every age group.

SCOTT: OK, Maria, so let's talk about some of those benefits specifically. So you mentioned earlier that indoor air quality can affect students' academic performance, right?

GODOY: Right. And, you know, I talked to Anisa Heming of the Center for Green Schools. She says in the past, it's been hard to make a health case for improving air quality in schools because studies of the health impacts and their effects on academics tend to be longer-term. But I was actually floored to find out that there's a whole body of research that shows the health and academic benefits are really substantial, and they go far beyond COVID.

So when a room is better-ventilated, influenza rates, asthma attacks and absenteeism go down. Reading and math test scores go up. Less carbon dioxide builds up in a room, which helps students think more clearly. And, by the way, researchers have actually seen these benefits in workplaces, too, where better air quality is linked with clearer thinking and more worker productivity. But now in the COVID era, improving indoor air quality, you know, also has the huge benefit of substantially reducing the risk of transmission. For example, one study of Georgia schools linked improved ventilation strategies combined with HEPA filtration to a 48% lower rate of COVID.

SCOTT: Wow. That is significant and great. So if a school does this right, what exactly needs to be done? - because, I mean, obviously, schools vary all around the country. Some of them are getting pretty old. So kind of give us the overall picture.

GODOY: Yeah, a lot of them are. And there was a recent government report that found one-third of all schools have outdated HVAC systems. Some don't even have mechanical systems to bring in fresh air. Last year the Center for Green Schools published a survey of more than 47 school districts representing 2.5 million students in 24 states. Anisa Heming of the center says the vast majority of school districts said they would like to invest in long-term solutions rooted in revamping or replacing their HVAC systems. But...

ANISA HEMING: We keep hearing the same challenge, which is that school buildings are in bad shape. And so they need, in some cases, pretty major renovations in order to implement some of these recommendations.

SCOTT: This is a steep hill to climb, but the Biden administration has provided several rounds of funding. What's been set aside for schools thus far?

GODOY: Well, so the Biden administration's national COVID-19 preparedness plan encourages schools to improve air quality using funds from the American Rescue Plan Act. And that's legislation Biden signed in March of 2021. There is more than $120 billion for schools in it on top of other emergency funding.

SCOTT: Yet when we're talking about not just upgrading old buildings but planning and building fully new buildings that have better airflow, that kind of work - that takes months, even years, right?

GODOY: Yes. But just this month the Biden administration has really put renewed focus on air. They updated guidelines with really clear recommendations of what schools and other building operators can do to improve air. They're really just sort of stepping up the role of indoor air quality as part of its pandemic response. Broadly speaking, Allan says, all the advice boils down to three major things - increase the amount of outdoor air in a classroom, use higher-efficiency MERV filters in HVAC systems, and then supplement these measures with portable air cleaners with HEPA filters. Allen says it's clear that while a lot of schools have taken steps to improve ventilation, many others haven't even done the basic stopgap measures.

SCOTT: So let's talk about those stopgap measures, some of which may be very helpful and can be as simple as opening windows and using portable air cleaners.

GODOY: Yeah. So research shows stopgap measures like opening windows or using portable air cleaners - they can really be effective at improving indoor air quality and reducing the risk of transmission. And Heming found that a lot of schools are taking these measures, but they can only take schools so far. It's not always as simple as it sounds.

SCOTT: Why not?

GODOY: Yeah. So, for example, Heming says if you open windows, it's not really realistic when outdoor temperatures are freezing. And then in humid regions, you know, open windows can pull in more humidity, which ends up promoting the growth of mold. And while many school districts have invested in standalone portable air cleaners, Heming says they actually come with their own headaches. These units can be destructively noisy and they need to be stored and maintained over time. That is why a lot of school districts would prefer to invest in a long-term solution like upgrading HVAC systems.

SCOTT: And a lot of people did some deep dives into the different air filters back at the beginning of the pandemic and discovered that they're not really all created equal. And especially with COVID, the industry has just exploded and started pumping out all sorts of filters with different technology that are making all sorts of claims that aren't always backed up by science. And in fact, from what I understand, there's even research that shows some kind of filters that use a process called bipolar ionization could actually make air quality worse and that a group of scientists released an open letter that had asked schools to actually stop using them, right?

GODOY: Right. So there are some engineers who will defend that technology. But I spoke with Marwa Zaatari. She's one of the authors of that letter asking schools to stop using this ionization technology.

MARWA ZAATARI: So there are, like, basically two things we need to know. One is about the effectiveness. Another one is about the safety.

GODOY: She says when tested in the field, these devices don't always perform as advertised. And there are some studies that suggest they can actually increase levels of ozone in a classroom, which is harmful to health.

SCOTT: So there's a lot of information that schools have to take in, oftentimes without a lot of staff to process it all and, I mean, make all these decisions. So what do we know about where schools stand with upgrades?

GODOY: Yeah, good question. And two years in, it's unclear how many schools have actually made these changes. That information just isn't tracked at the federal level. But there are some reports that hint at the challenges schools have faced. As we mentioned, it takes many months to plan and contract the kind of HVAC overhauls that many schools need. Heming of the Center for Green Schools says, in a lot of cases, those plans are only being firmed up now. And a recent survey found many school districts are worried that they're not going to be able to complete the work by a September 2024 deadline under the law, especially because of supply chain issues and labor and material shortages, which we've all heard of.

SCOTT: So you're saying they would actually have to give them money back before they have a chance to use it.

GODOY: Well, they wouldn't be in compliance with the rules for using that money, so they would essentially be left holding the bag. Technically, they have the money already, but they would have to give it back.

SCOTT: Wow. But I guess the flipside is this renewed attention and more funding. I mean, there surely has to be some good news here, Maria.

GODOY: Yeah. Yeah, I think there is. There are signs that more schools may be catching up soon. An analysis released in February by FutureEd - that's a think tank at Georgetown University - it found that school districts already have plans in place to spend about $4.4 billion on HVAC updates. And if trends continue, that could reach nearly $10 billion. Now, Heming of Center for Green Schools says she's optimistic, but her enthusiasm was tempered. She says the, you know, over $120 billion in American Rescue Plan funds that were designated for schools have to pay for a lot of pandemic-related needs, from hiring more staff to summer school programs, in addition to ventilation upgrades. So there's just a big gap between that and what's actually needed to get schools in good condition.

SCOTT: Tempered optimism. I feel like in a global pandemic, that might be all we can ask for sometimes.

GODOY: (Laughter) Yeah.

SCOTT: So thank you so much for bringing us this reporting, Maria. I love talking about air filtration.

GODOY: You know what? That's strange because so do I.


SCOTT: Today's episode was produced by Eva Tesfaye and edited and fact-checked by Gisele Grayson, who is also our senior supervising editor. The audio engineer for this episode was Neil Tevault. Andrea Kissack runs the news desk. Edith Chapin is the executive editor and vice president of news. And Nancy Barnes is our senior vice president of news. I'm Aaron Scott. Thanks for listening to SHORT WAVE, the daily science podcast from NPR.

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