How schools monitor and control air quality

The COVID-19 pandemic put the importance of indoor air quality in stark relief. The air in schools was of particular concern, and that concern spurred collaboration between researchers and school staff to find interventions to improve air quality to safeguard the health of students and staff. Data from indoor air monitors revealed that filter-based portable air cleaners were effective at removing airborne particulates. Ongoing research and monitoring will determine whether this effort is making a beneficial health impact and will be used to decide how to manage indoor air quality going forward. C&EN Uncovered, a project from C&EN’s podcast, Stereo Chemistry, offers a deeper look at subjects from recent stories. Check out the full story about air quality monitoring in schools at cenm.ag/airqualityinschools.

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Executive producer: David Anderson

Episode artwork: Glenn Asakawa/University of Colorado Boulder

Music: “Hot Chocolate” by Aves

Contact Stereo Chemistry: Contact us on social media at @cenmag or email [email protected].

The following is a transcript of the episode. Interviews have been edited for length and clarity.

Craig Bettenhausen: Welcome to C&EN Uncovered. I’m Craig Bettenhausen. C&EN Uncovered is a podcast series from Stereo Chemistry. In each episode, we’ll take another look at a recent cover story in Chemical & Engineering News and hear from C&EN reporters about striking moments from their reporting, their biggest takeaways, and what got left on the cutting-room floor. At the beginning of the COVID-19 pandemic, one of the chief concerns was how to get children back in schools—safely. Once health officials publicly accepted that the virus was primarily transmissible through the air, schools made concerted efforts to monitor and improve the air quality in their classrooms to make them safe for students. In a story that appeared in the Sept. 2 print issue of C&EN, today’s guest looked at ongoing programs in Colorado and Massachusetts designed to help schools identify, monitor, and mitigate air quality issues in their classrooms. We’ll put a link to the story in today’s show notes. I’m here with C&EN assistant editor Fionna Samuels, who wrote the article. Hello, Fionna!

Fionna Samuels: Hi. Thanks for having me.

Craig: So, for anyone that hasn’t had a chance to read the story yet, can you give a brief recap of what’s in the article?

Fionna: Essentially, I talked to two researchers who are continuing to do indoor air quality monitoring programs with schools in Colorado and Boston, Massachusetts, and then sort of tied it all together with a little bit about the ongoing sorts of pushing for regulations that’s happening across the country.

Craig: And what attracted you to this as a story topic?

Fionna: I think that I, like many other people, got very concerned about the indoor air quality around me during the COVID pandemic, and I knew that Mark Hernandez, one of the researchers that I talked to, started working with schools during the COVID-19 pandemic, and I was really interested in following up and seeing where that research was now. And it turned out that they basically have finished installing indoor air quality monitors across Colorado, and now they’re really digging into how indoor air quality might be affecting absenteeism. And from him I learned that there’s other programs in other places in the country, like the one in Boston, which sort of led me on to talk to Patricia Fabian. And then again, I wanted to know what the state of regulation was, which is when I talked to the EPA [US Environmental Protection Agency] folks.

Craig: So the COVID-19 pandemic was the catalyst for all this monitoring. How has that evolved now that we’re settling into something like a new normal?

Fionna: The major point is just because COVID-19 sort of put a focus on indoor air quality, that doesn’t mean that indoor air quality has improved since then. Indoor air quality has always been important, and it’s just that the pandemic sort of spotlighted that importance for the general public. Now I feel like the focus has really shifted towards sort of the idea that indoor air quality, more generally, is important to monitor and improve, rather than sort of hyperfixating on COVID specifically.

Craig: So, what steps did schools take to improve air quality in the classroom?

Fionna: In Colorado, across the state, schools have installed HEPA [high-efficiency particulate air] filters, portable HEPA filters, as well as indoor air quality monitors. And then in Boston, specifically in that one school district, schools have done the same thing. And this is not unique to Colorado or Boston. There are other schools in the country who are installing, or the districts are installing, air quality monitors and HEPA filters. One thing that didn’t make it into the story was that in the middle of the pandemic, at the height of the pandemic, schools had a lot of funding to improve indoor air quality, and what ended up happening is that companies sold indoor air purifiers that were not actually effective. There’s been some litigation surrounding that sort of exchange of money for ineffective indoor air purifiers. But HEPA filters do work. HEPA filters and ventilation are the two big things. So just getting the air that’s inside out and exchanging inside air for outside air if the outside air is clean.

Craig: So Mark Hernandez’s team in Colorado set up monitoring systems with the air purifiers. What were they measuring exactly?

Fionna: In Colorado, they measure temperature, humidity, VOCs [volatile organic compounds], carbon dioxide, and particulate matter, but they have measured particulate matter in two sizes. They do pm 2.5 and pm 10. So that’s particulate matter that is smaller than 2.5 µm in diameter, and particles that are smaller than 10 µm in diameter. Those have slightly different health effects, but both of them are not good for you.

Craig: For VOCs, again, where do these pollutants come from, especially in the home?

Fionna: VOCs can come from a lot of places. It’s actually very interesting and a really broad area of research for indoor air chemistry. VOCs come off your skin. They come off of your cleaning products. So anything that smells, that’s like a VOC. So if you have a really pungent perfume, that’s a VOC. I had some friends who were atmospheric chemists, and they were doing some indoor air quality monitoring at Colorado State University. One of the researchers had to be told to stop wearing such pungent sunscreen, because the sunscreen was showing up in their data. Easy answer is, anything that smells is probably a VOC. Not all of them are, you know, terrible for you. Obviously.

Craig: As a side note, when I was reading the story, I loved coming across the term “dab pens” in C&EN. You know, cannabis is becoming more mainstream every year, but it’s still surreal for me to hear that sort of thing discussed openly.

Fionna: Well, that was something that Mark said. He said that they can always see when the students are smoking anything, and I guess students or teachers, when anyone is smoking anything in the building that shows up. So I guess, don’t smoke around indoor air monitors. Or try to be sneaky.

Craig: So what are the negative consequences that can arise from not doing a good job at this, from not having good air quality?

Fionna: There’s a lot. I mean, the obvious one is increasing respiratory disease. We all experienced that with COVID. I guess one thing that is important to highlight with this is that there’s not so many standards yet. So for example, there’s not a standard for what bad levels of CO₂ means. There’s not a number. But something that Patricia Fabian brought up was that during the pandemic, there’s this idea that 1,000 ppm of CO₂, so 1,000 parts per million of carbon dioxide, meant that you were more likely to get COVID. But that doesn’t totally make sense, because if you’re standing next to someone with COVID, you’re probably going to catch it, regardless of what the concentration of carbon dioxide is. When we’re talking about, like, What are the negative consequences of bad indoor air? there’s not enough research at this point, really, to say anything more than, you know, you don’t want to be in a space where there’s a bunch of virus particles. You don’t want to be in a space where there’s potential carcinogens that are floating around in the air. You don’t want to be in a space that’s full of smoke or particulate matter that can get down in your lungs and cause pulmonary issues. But beyond that, there’s not a lot of concrete numbers. Can’t say it’s safe to be in a space that’s less than 100 or 1,000 ppm of CO₂, right?

Craig: So we’ve talked a fair amount about Colorado already, but you also talked to folks in Boston. How is the program different there, and what’s the status?

Fionna: The biggest difference is that the general public can actually access all of the air quality monitoring data in Boston, whereas in Colorado, as far as I can tell, that’s sort of privately held for the schools to access but not necessarily the public. The other thing is that Boston doesn’t measure VOCs. They measure carbon monoxide, and the reason they measure carbon monoxide is just because that’s a super dangerous gas. But other than that, they’re very similar. You know, the researchers are trying to help interpret data for the school districts, and in both cases, there’s a really big push to inform the school districts before potentially informing the public. For Boston Public Schools, you can go and see how the indoor air is in every single school in that district.

Craig: Yeah, the transparency is really interesting. A plug for your story again: At the bottom, you have a link to this tool, and you can, just like, zoom right in. It’s a map, and it has the numbers right there.

Craig: In Boston, yeah. At the same time, raw data can be scary, especially for parents that might not have a scientific background. How good a job are the schools doing at putting the context out with the data?

Fionna: The point is that this resource is there so that parents who are involved can sort of push the school to act on it. It’s a really good resource for building managers. But like you’re saying, building managers are going to have to have some level of understanding of how to read graphs, which might be challenging, but I think that there is—I mean, the scientists that I talk to were very enthusiastic about trying to inform and help in any way they could in terms of teaching people how to use these tools, “people” being the school administrators, the building managers, and everyone who’s sort of involved in keeping the building safe.

Craig: So what has been the overall effect of the purifiers in the Colorado pilot program?

Fionna: The overall effect of the purifiers seems to be that they very effectively remove particulate matter. And there’s a significant difference before and after the purifiers are used. More importantly, again, is the ventilation. The indoor air purifiers are an important aspect of the story, but probably the more important piece is the monitoring, because with the monitoring, Mark and Patricia can both say pretty confidently that ventilation makes a difference. Or, This purifier is making a difference. Without the monitoring, we would have no idea. My sort of interpretation is that, yes, the technologies to clean the air are good and helpful, but more important is to monitor everything so that you can actually see if they’re good and helpful rather than not good.

Craig: So another person in your story is Patricia Fabian at Boston University. Can you talk about their work?

Fionna: So Boston Public School District installed a bunch of monitors in their schools, as well as filters, and Patricia saw in a news article somewhere that all of this monitoring was happening, and she really wanted to get involved in analyzing that data. And so her whole focus is taking the data from the monitors and basically digesting it into something that is able to be used by the schools and the administrators, building managers, whomever, to basically get more funding to address specific problems at those schools and to identify the problem areas so that things can be fixed in a way that makes the most sense, basically triaging the worst case rooms first rather than focusing on ones that are fine.

Craig: Yeah, that’s an interesting nuance in your story, that talked about how even within the same school building, sometimes there was one classroom that was great and one classroom that was in a real rough state.

Fionna: So that variability is why she thinks that it’s really important to put a monitor into every single classroom and every single really important space. So they have it in the nurse’s office and the administrative offices. In Colorado, they don’t put them in every single classroom, but in both cases, you can see variability. Based on what Patricia was saying, like, you can literally see one classroom is much warmer than the classroom next door.

Craig: So when I think of air quality, one of the first entities I think about is the EPA, but the EPA hasn’t been able to step in yet. Why is that?

Fionna: They don’t have any regulatory power in indoor spaces. So we have the Clean Air Acts for outdoor spaces, where the EPA can do some regulating, but there’s no sorts of regulatory power for indoor spaces. And I mean, I would assume it’s because indoor is considered private.

Fionna: That might change, though.

Craig: Yeah, I was gonna say, because your article mentioned that there’s some legislation in the works that could change that.

Fionna: The legislation that’s in the works is basically focusing on trying to basically enable regulatory bodies to get into public spaces and do something about the indoor air quality in public buildings.

Craig: So there would be a new law that would give the EPA authority in that space.

Fionna: Yeah, so the law actually will give the EPA the ability to get into those indoor spaces and have a say about what is considered good or bad air. And they have some pollutants that are on the list that need to be monitored. And the bill will also allow the EPA to add more pollutants as more information and data are acquired by scientists.

Craig: And that’s at the federal level? Is there a bill name you can point us to?

Fionna: Yes. So the bill is called the Indoor Air Quality and Healthy Schools Act of 2024, and it was introduced by congressmen Paul Tonko of New York and Brian Fitzpatrick of Pennsylvania. It seems like something that aligns with what a lot of the indoor air scientists are hoping to see.

Craig: So from a very practical sense, what resources are available now to schools that want to improve their ventilation and purification systems?

Fionna: So right now, there are still potentially unspent ESSER [Elementary and Secondary Schools Emergency Relief] grants from when the Biden-Harris administration was funding schools, specifically elementary and secondary schools, to reopen during COVID. In addition to that, there’s the Inflation Reduction Act, and also the White House has this thing called the Clean Air and Buildings Challenge, which also has some funding resources. And the EPA has been funding a lot for scientists who want to get involved in helping learn more about indoor air quality, but that’s sort of a separate thing than schools.

Craig: Yeah. So this is going to be hard to answer, because schools come into different sizes, but I wonder if you could give a sense of the costs that an average-size school would be looking at to overhaul their ventilation system. What does it cost to really fix these problems in a normal school building?

Fionna: It can cost a lot to fix the ventilation or to fully replace the ventilation. That can be a very significant amount of money, like $10,000 or something. Something Mark Hernandez was very adamant about was the fact that when you break down the cost of installing indoor air quality monitors and the short-term solution of these HEPA-filter-based air cleaners, it breaks down to about the cost of a cup of coffee every day per student, because there are so many students that if you consider every student, you kind of disperse the cost across a lot of young people. So I mean, it seems like it would be worth it, especially if you can use the grants that are available from the federal government to sort of subsidize or to cover those costs.

Craig: Slightly distracted by the idea of someone clipping out that one audio clip and having, “Fionna endorses a cup of coffee for every student.”

Fionna: Every student should have a cup of coffee.

Craig: I’m terrified of what would happen if you put some of these air quality monitors, especially for VOCs, in a chemistry lab, speaking of other spaces that might give you unpleasant results.

Fionna: Yeah, I would be worried about that too. I mean, I think that that’s honestly—

Craig: And those windows don’t open, usually.

Fionna: The windows don’t open. Some of the vent hoods don’t work. It’s probably even more important to be monitoring those spaces—

Craig: I guess that’s true.

Fionna:—especially when you don’t know the kinds of things that are going to end up in the air, depending on the reactions that you’re running. Again, while this story focused on schools specifically, it’s not unique to schools. So installing indoor air quality monitors is something that, especially Mark Hernandez thinks is something that we should be doing across the board in all public spaces. Just because information is powered we spend, you know, a huge amount of our life in buildings. We’re constantly at the ACS [American Chemical Society] office, right? The other day, I was smelling lemongrass in the hallway, and I had no idea where it was coming from. So it would perhaps be nice to be able to look at a dashboard and say, like, Okay, even though I smell this weird thing right now, I can tell that we’ve got enough ventilation that the air exchange rate is high enough to protect me from any sort of bad pollutant, or offer some measure of protection against bad pollutants. Monitoring is power, and that’s kind of the overall point beyond just schools.

Craig: Fionna, thanks for diving deep with us on this.

Fionna: You’re so welcome.

Craig: So listeners can find me on social media as @craigofwaffles. How can listeners get ahold of you?

Fionna: My email is on the C&EN directory, which is totally open to anybody. Anybody can email me.

Craig: You can find Fionna’s cover story about air quality in schools on C&EN’s website or in the Sept. 2 print issue of C&EN. We’ve put a link in the show notes along with the episode credits. We’d love to know what you think of C&EN Uncovered. You can share your feedback with us by emailing [email protected]. This has been C&EN Uncovered, a series from C&EN’s Stereochemistry. Stereochemistry is the official podcast of Chemical & Engineering News. Chemical & Engineering News is an independent news outlet published by the American Chemical Society. Thanks for listening.