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!

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