6 Months of guerilla CO2 measurement with the COVID CO2 tracker

It’s been six months since I started work on an app to crowdsource CO2 measurements as a COVID mitigation effort. Volunteers (“CO2 guerillas”) across the world have since added nearly 600 measurements to the database, as part of an effort to document safe and dangerous indoor spaces.

The app (deployed at: https://covid-co2-tracker.herokuapp.com/home) was born out of the need to improve indoor air quality in the middle of a highly contagious airborne respiratory pandemic. Somehow – more than a year into this – governments around the world deny the very fact that this virus is spread through the air, not through surfaces and “droplets”. This was obvious from the very beginning to me, and to hundreds of aerosol scientists, safety engineers, HVAC specialists, and even entire countries where SARS-1 epidemics hit in the past.

After trying desperately to spread the word on my own throughout 2020, I decided to get involved in organized advocacy and work to protect the public, and save lives. Since February 2021, I’ve been involved in several groups of experts and world-renowned scientists. Back then, I was growing increasingly distressed at our lack of organized and systemic data on the indoor air in places where the public interact most. Sure, it would be great if the government took steps to make this data available to the public, but they had failed to do so for the entire pandemic. At that point, I noticed the large numbers of people posting CO2 measurements from public places on twitter! As a long time software developer, and slightly experienced web developer, it was obvious that I could build something to organize and share these measurements.

I decided it was important to get it out as quickly as reasonably possible – people are dying, that’s an emergency – so I decided to not try anything fancy, and do what I know. It’s a simple Rails + React/Typescript app deployed to Heroku. It was four weeks from inception to MVP. I was in enough of a hurry that there’s minimal testing 🙂

All of the people submitting data to the app were either recruited directly by me through twitter, or by word of mouth! I tried to get some attention through reporters who were writing about CO2 measurement (there were a number of wonderful articles written in The Washington Post, The Verge, and many others) but I never received a response. Throughout the pandemic, there has been a constant onslaught of snake oil salesman and crackpots writing to the media, so I’m not too surprised.

There are also a few businesses in this space, selling CO2 tracking solutions to businesses and schools. My app is currently not a for-profit endeavor. I have toyed with the idea of selling a realtime upload feature for stores and institutions (think: charging $1/month to upload from an aranet4 automatically every 15 minutes), but there doesn’t seem to be much of a market for it here! So it will remain a volunteer only app for now.

I have also had plenty of excellent advice from experts in understanding the dynamics of CO2, and to validate some of the assumptions and calculations involved. Prof. Elena Jiménez of the University of Castilla-La Mancha was quite helpful and responsive early on. The scientists in the twitter groups I’m in have also been quite helpful individually. They all deserve thanks and recognition for helping me here, and generally being responsive to emails from strangers and the public!

Should the app continue to be of use to people, and more people contribute data to the database, I will be able to start building more powerful and more useful tools. The easiest to build will be basic statistics for the data that’s been collected. Averages, high and low numbers for certain models of CO2 meters, and maybe even drift over time. Once there’s a critical mass of data, there’s more of an opportunity to show and filter places by the quality of their indoor air! At that point, a non-volunteering member of the public will be able to see the places they visit, and make safety decisions based on the real world information that has been collected. This will be far better than the trusting that places abide by blanket pandemic regulations, many of which are entirely opaque.

Because of the way that the Google Places API works, it will be considerably more difficult to sort and filter locations by type (e.g. supermarket, restaurant, etc…). I’m not sure how I’ll solve that, but I’m sure there are ways to workaround it.

As we deal with the spread of vastly more contagious variants, I hope that we as a society recognize the need for safer indoor air. In the long run, I hope that we will all work to improve the quality of the air that we breathe, pandemic or not. When the time comes, we’re ready to help.

~ by Alexander Riccio on August 10, 2021.

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