COVID-19 Data Dispatch

Tag: co2 monitor

  • How my partner and I stayed safe during summer travel

    How my partner and I stayed safe during summer travel

    Betsy and her partner’s portable HEPA filter, pictured on the train from Berlin to Brussels. Her partner (in an N95 mask) is visible in the background.

    A few days ago, my partner and I returned home from a two-week vacation to several cities in Europe. It was our first time traveling internationally since before the COVID-19 pandemic, and the trip required a lot of time on planes, on public transportation, and in crowded spaces.

    I’m sharing what we did to reduce our risk of COVID-19 (and other common pathogens!) during the trip, in the hope that this will be helpful for readers traveling this summer. While taking these sorts of precautions may be increasingly unpopular in many places, these measures still reduce the risk of illness for individual travelers and the people around them.

    Here’s what we did:

    • Reduced potential exposure and tested before we traveled: It’s pretty typical for me to avoid crowds and indoor events prior to traveling. In this case, my partner and I did attend Pride marches in New York City the weekend before our trip, but we only attended outdoor events and wore masks in the crowds to reduce our risk. We also both got PCR tests the day before leaving (we’re lucky to live near one of the few public testing sites in the city that are still open).
    • Masked indoors, with high-quality masks: I consistently wore N95 masks on the trip, including my reusable respirator on planes. (I wrote more about my respirator in this post last summer.) My partner also wore an N95 or KN95 throughout the trip. We have different preferences for which masks fit us well, so we had a few masks of different brands packed to accommodate that.
    • Avoided indoor dining (as much as possible): All of our meals were outdoors. My partner is vegan, so any restaurant where we ate had to fit into a Venn diagram of “vegan options” plus “outdoor seating”; this might sound challenging to find, but with a bit of planning—and with thanks to the Happy Cow app—it was actually quite doable. We had to eat briefly on planes at a couple of points, but we minimized that time as much as possible (eg. masking in between bites) and did so only when plane air filtration systems were going.
    • Took advantage of smoking sections: European cities tend to have a more prominent smoking culture than the U.S., so many restaurants and bars have outdoor smoking sections. This can be a tricky situation for COVID-cautious travelers; yes, you’re outside, but you’re also breathing in a lot of second-hand smoke. Still, my partner and I found these sections to be a helpful option. We even had lunch in an outdoor smoking zone at the Keflavik Airport (in Iceland) during a layover on our way home to NYC.
    • Used a CO2 monitor to gauge ventilation in some spaces: I am a proud owner of an Aranet CO2 monitor, which I mostly use to track ventilation at my apartment and public spaces in NYC. I brought the monitor on the trip, and used it to identify which public buildings had better air quality. For example, train platforms at Berlin Hauptbahnhof (the city’s central train station) are open to outdoor air and have frequent airflow, as evidenced by a CO2 reading I took of 611 ppm—well within the Aranet monitor’s “green zone.” So, I felt comfortable taking off my mask there for a few minutes to drink coffee.
    • Used a HEPA filter on trains, hotel rooms: My partner and I have a personal, portable HEPA filter that runs on a battery and fits easily in my duffel bag. I brought it along on the trip and used it a few times, mostly on crowded trains and in hotel rooms that did not have great airflow. It also doubled as an extra fan in our Airbnb in Amsterdam (which was not air-conditioned).
    • Rapid-tested every two days: Over the two weeks of traveling, my partner and I took a rapid test every two days to check for any developing illness. We also requested testing from friends and family members with whom we spent time indoors, such as a friend whom we stayed with in Berlin.
    • Testing and symptom monitoring after getting home: Since arriving home in NYC on Wednesday evening, my partner and I have each gotten PCR tests. I also rapid-tested once, as an extra check before attending an event on Thursday. We’re planning to do another round of PCR testing next week and monitor for any symptoms; so far, we haven’t seen any signs of illness.

    I acknowledge that these safety measures may sound like a lot of effort. Certainly, tools like rapid tests and a personal HEPA filter cost money, and may not be accessible to many people. And in an ideal world, everyone would be able to travel in a world where these tools are free and commonplace, rather than a reason for extra advanced planning.

    There are also increasing social pressures to not take precautions, especially in some of the places that we visited. I had a few conversations with strangers who insisted I was strange for wearing an N95, that COVID-19 was “over”; I was even patted down and pulled into a security screening at the Amsterdam airport by guards who decided my respirator was suspicious.

    I am the kind of person who doesn’t back down to this pressure, especially when I have the research and reporting to back up my convictions. But I don’t want to be an isolated person taking precautions in a sea of others who aren’t acting to protect public health.

    Broader change is really needed; in the meantime, though, I hope my experience is informative for others.
    If you are also traveling this summer and you have other tips you’d like to share with the COVID-19 Data Dispatch community, please send them to me! You can email me or comment on this post.

    SIGN UP FOR WEEKLY UPDATES
  • Q&A: Libraries lend out CO2 monitors to make public health data more accessible

    Q&A: Libraries lend out CO2 monitors to make public health data more accessible

    This map shows libraries across Canada that have set up CO2 monitor lending programs with CAVI.

    Two weeks ago, I shared that I’d recently purchased a monitor to measure CO2 as a proxy for ventilation in my apartment and other spaces. That post led to responses from several readers who’ve also been using CO2 monitors—including Kate Nyhan, a research and education librarian at Yale University who specializes in public health.

    Nyhan explained that, in addition to using a CO2 monitor at her home and workplace, she co-founded a nonprofit that helps public libraries loan out monitors. This nonprofit, called Community Access to Ventilation Information (CAVI), has brought CO2 monitor access to libraries serving about one in five Canadians. In addition to the monitor-lending, CAVI develops educational materials to help library patrons use these tools and collaborates with other air quality initiatives.

    I talked to Nyhan and Danielle Cane, CAVI’s managing director, to learn more about the organization and get their tips on using CO2 monitors. Here are the highlights from our conversation. 

    How CAVI started

    Cheryl White, an engineer and air quality expert based in Toronto, Canada, got the idea for this organization in fall 2021. At that time, many people on the COVID-conscious side of Twitter started to express interest in air monitoring, Cane said.

    “When we would post our readings from CO2 monitors on social media, a lot of people were saying, ‘This is really cool, I’d love to get involved,’” she recalled. “But it’s just so expensive to access these tools.” Higher-end monitors, like the Aranet device I purchased, can cost around $300. 

    White had the “bright idea” to partner with libraries as a way to make these monitors more accessible, Cane said. After Cane and Nyhan came onboard, the group reached out to Peterborough Public Library, a library system in a town northeast of Toronto. (Cane and White are both based in the area.)

    “Peterborough Public Library was really game to introduce this program,” Cane said. CAVI also worked with the local public health department, which helped gain buy-in for lending out air monitors. The initial Peterborough pilot was launched in spring 2022 with 15 monitors, supported by funding from Canadian and American Aranet distributors.

    The city of Toronto later joined the program, followed by other Canadian municipalities. Right now, about 22% of Canadians “have access to a co2 monitor through a public library,” Cane said. CAVI received additional funding in late 2022 to expand further. While the monitor-lending is focused on Canadian libraries, CAVI also produces free, open-source educational materials that can be used in other places.

    Why do this in libraries?

    Nyhan explained that libraries are well-poised to make air monitors more accessible. “Libraries want to empower community members with access to information,” she said. “In the context of indoor air quality, or COVID transmission risk mitigation, that might be information about airborne transmission, that might be about information about mitigations like air filters… It might be as tangible information as, what’s the number of CO2 parts per million in the space that I’m in right now?”

    Lending out CO2 monitors also fits into the “Library of Things,” a concept in which libraries lend out non-traditional items—ranging from home repair tools to arts and crafts materials. As an expensive item that can provide valuable information to the community, CO2 monitors are a great addition to many libraries’ existing collections. In addition, some libraries already have people on staff with public health expertise or existing programming in this area, Nyhan said.

    How the program works

    The lending system tends to vary from one library to the next, but most places are loaning out CO2 monitors for one week at a time, Cane said: “Especially given the demand in certain areas, like big cities, we find that the one week schedule tends to work out best to both balance, giving people the opportunity to check a variety of settings… and allowing other people to also have that same opportunity.”

    Some libraries have seen high demand, especially when the CO2 monitors first arrive at a new library. But as demand levels out over time, patrons might be able to “renew” their loans to keep the monitors for an additional week, Cane explained. Along with the physical monitors, libraries can point patrons to educational resources from CAVI that help interpret the findings.

    Interpreting CO2 monitor data

    As I’ve found in my own CO2 monitor adventures, there’s a lot these devices can tell you—but also a lot they can’t tell you. The biggest caveat, Cane explained, is that CO2 monitors are “a proxy for ventilation,” not a “proxy for infection risk.” In other words: a really high CO2 reading in a particular space doesn’t necessarily mean that infection is guaranteed, especially if other safety measures are in place. And “a really low reading doesn’t necessarily mean that you will not get infected,” Cane said.

    Aranet monitors have a built-in interpretation feature, marking certain CO2 readings as green (good), yellow (less good), and red (bad). But CAVI has produced materials that go into more detail about explaining the ppm (parts per million) measurements. Cane shared one document, designed in partnership with Toronto Public Library, which goes into detail on what higher CO2 readings mean and how to act on them.

    Taking action based on CO2 readings

    Nyhan used the example of a small car to explain how people may take simple actions based on their CO2 monitors’ results. “Even if it’s just a single person, because [a car is] such a small and tightly enclosed environment, you can very quickly see the impact of breathing out, or opening the window, or changing the air to recirculate or not,” she said. Opening a window or telling the car not to recirculate brings in more outdoor air, causing CO2 levels to get lower.

    This is a fairly simple lesson that a library patron might learn during the one week they have with a monitor, Nyhan said: “You learn that, and then you can give the CO2 monitor back to the library so someone else can use it.”

    In a larger space, actions based on high CO2 readings might include adding external air filters, opening several windows, or hiring an HVAC engineer to evaluate the ventilation system, Cane said. Not everyone might have the capacity to hire an HVAC engineer, but many people can buy or make air filters; Corsi-Rosenthal boxes are one popular DIY model that can be constructed with commercially available box fans and filters. CAVI has recently partnered with a Canadian high-schooler who’s worked to build these boxes and share accessible instructions.

    Nyhan also pointed out that CO2 monitors are “not just for people who control their own spaces” and can easily make ventilation changes. CO2 readings could also inform behavioral safety measures, she said, such as rapid testing before a social gathering in a poorly-ventilated apartment or avoiding certain poorly-ventilated parts of one’s workplace. In some cases, these readings could even be used to advocate for ventilation changes.

    Next steps for CAVI

    CAVI plans to continue expanding among public libraries in Canada. The organization also works with libraries elsewhere that may want to set up their own CO2 monitor lending programs, Nyhan said. Library staff and users are welcome to reach out to the CAVI team to learn more about the project: “We can share best practices, educational materials, assessment tools, grant proposals,” Nyhan said.

    While CAVI, like other air quality citizen science efforts, is currently focused on mitigating COVID-19 risks, its work has implications for many other public health threats. “If we have a wider acceptance of how respiratory pathogens are transmitted, it could be useful to help mitigate other viruses, other bacteria,” Cane said. Improving ventilation can lower the chances of infection for many pathogens and reduce the health risks associated with indoor air pollutants. 

    Lending out air monitors fits into work that some public libraries are already doing on environmental health, Nyhan said. Libraries might have existing programs about wildfire smoke, radon, and similar air quality threats; COVID-19 and pathogens like it provide motivation for expanding these efforts. “Indoor air quality, and environmental health more generally, is a hot topic that’s only going to get more important,” Nyhan said. 

    More on air quality

  • How COVID-19 Data Dispatch readers use CO2 monitors

    Last week, I wrote about my experience with a CO2 monitor that I recently bought, and have been using to informally study the air quality in my New York City apartment. I asked readers to share their experiences with these monitors, and several of you did!

    Here are some snippets from those responses; I hope it will be helpful for some readers to see how other folks are using air quality monitors.

    Joyce R.:

    I bought a much less expensive one (this one for $60), and I’ve been using it in my downtown office that I go to twice a week (it’s a WeWork facility and I’m in a small 2-person office there; my co-worker and I take turns using it so only one of us is in it at any given time). I of course am always masked in the building—unlike about 98% of the other tenants, sadly—except when I eat (alone in my office, or outdoors on the roof if the weather is good enough). I also have one of those personal HEPA air purifiers going all day. The monitor is showing that usually the range is 800-900, so I’m pretty happy with that.

    Mark:

    I have an Aranet4 and I’m amazed at the accuracy of it. I put it in my kid’s backpack and could track when he changed classes, went outside or got on the bus. It was REALLY interesting.

    In a follow-up email, Mark added:

    When I got his class schedule, the changes matched up to the exact 5 minute windows of changes. When I saw high numbers and asked my kid (who couldn’t see the numbers) what the class was like, he said ‘biggest class, 30 kids.’ Yep, the CO2 monitor picked it up. Really really impressive.

    Kate:

    Not only do I use a CO2 monitor to make risk decisions in my personal life—which shops and concert venues to avoid, are the university shuttles where I work safe (no), what setup of windows and fan make my car safer, what is the natural ventilation air exchange rate… But also, I used CO2 readings to persuade my boss to get facilities to fix a broken vent in my workplace… And EVEN BETTER, the non-profit I co-founded, ‘Community Access to Ventilation Information,’ has been helping libraries in Canada and the US lend patrons CO2 monitors and understand how to act on the readings.

    I will be talking to Kate and her co-founder at Community Access to Ventilation Information this coming week, and plan to share a Q&A based on that conversation in next Sunday’s newsletter. If there are any specific questions you’d like me to ask them, please reach out!

  • Collecting imperfect environmental data with a CO2 monitor

    Collecting imperfect environmental data with a CO2 monitor

    A chart from the Aranet app shows CO2 concentrations in my apartment over the last week.

    I recently bought a carbon dioxide monitor, and have been using it to collect data in my apartment and other places. In the week since I’ve been monitoring, I’ve noticed how personal data collection like this can be helpful in identifying ventilation issues, but comes with many caveats.

    You might have seen photos of these devices on Twitter or in news articles; they’ve become an increasingly popular way to measure ventilation in public spaces, as a proxy for potential risks of COVID-19 spread. The basic theory is that CO2 builds up more in spaces where there’s not a lot of clean air circulation. So, when you see higher CO2 readings, that indicates less clean air coming in, which likely means COVID-19 and other viruses could be hanging around for longer, too. Higher CO2 is also correlated with other health risks, like headaches and diminished neurological function.

    My CO2 monitor has mostly lived on the desk in my home office for the last week, with a couple of outings (to the park near my apartment, on the subway, etc.). I’ve been surprised by how much CO2 varies even in this one spot. A few observations:

    • The highest peaks of CO2 concentration usually correspond with cooking, since my kitchen has a gas stove. Even though my desk is across the apartment from the stove, the gas is still enough to send the meter above 1,500 ppm or higher.
    • CO2 concentration also tends to increase when there’s more conversation in the room, such as me doing Zoom interviews or talking to my partner, who shares the home office. (Talking puts more particles into the air than just breathing.)
    • CO2 concentration tends to drop when the room is empty and/or when the electric heater is turned off, leading to lowest levels overnight. (Our apartment has electric heating/cooling units instead of older-school radiators, and my desk sits right underneath the one in the office. Do these units expel CO2? I need to do more research here.)
    • Opening the office’s window usually corresponds with a decrease in CO2 concentration, though not as significant a decrease I’d expect given that the CO2 concentration outside is much lower—around 400 to 500 ppm. Perhaps opening the window further would lead to improvements, but it’s too cold in New York City to test that right now.

    Of course, it’s hard to explain every single uptick and downturn in the CO2 monitor’s readings. I also have to acknowledge that a device I can buy for $250 on the internet is far from perfect; it has quirks and errors that will take me much longer than a week to fully understand. Still, I’m enjoying this small-self experiment into my environment.

    Overall, the CO2 monitor has shown me and my partner that our apartment is not particularly well-ventilated. The CO2 concentrations in our office often range from 1,000 to 1,400 ppm, which indicates poor airflow. (Under 1,000 ppm is generally considered a safe level.) I’ve taken the meter on the subway a couple of times, and found that subway cars may even have lower CO2 than our office, if the car isn’t too crowded.

    We were already thinking about buying an air filter for the apartment, and the CO2 results add some urgency to this task. Also, the next time we move, we’re going to look for places without gas stoves—often a challenging task when you’re renting in New York City, but there are some options.

    Have you used a CO2 monitor, or tried to upgrade the ventilation in your home? I’d love to hear from you about it: comment below or reach out via email.