This App Could Solve a Big Reopening Problem

(Bloomberg Opinion) -- Ventilation is perhaps the most underappreciated challenge of reopening during the Covid-19 pandemic. As people increasingly return to indoor spaces such as office buildings, airports, schools and restaurants, they'll need plenty of outside air, so they won't walk into a cloud of coronavirus spray. But how can they trust building managers to ensure it's safe to breathe?

They can't. Which is why I think people need to cooperate – with the help of technology – to monitor air quality themselves.

Through tragic trial and error, we now know some things about Covid-19 transmission. Being outside, socially distanced and wearing masks is pretty safe. Being crowded inside with poor ventilation is not. The pandemic's surge in the southern and western U.S. has a lot to do with people seeking refuge from the summer heat in spaces where air-conditioning systems recirculate inside air, exposing them all to each other. Northern states will face a similar problem soon, when colder weather forces more people inside.

Pre-Covid trends in building design don't help. Consider modern offices. Open plans and tightly sealed windows might be great for productivity and energy efficiency, but they're problematic from an epidemiological perspective. Even before the pandemic, sealed buildings presented an air quality issue: Carbon dioxide levels could spike if ventilation systems failed to handle all the human exhaling. At levels exceeding 1000 parts per million (compared with the typical 400 ppm outside), the pollution could cause drowsiness and headaches, symptoms associated with “sick building syndrome.”

The upside of the CO2 issue is that it provides a proxy for a building's Covid safety. It's not perfect: Levels could be elevated due to environmental factors other than too many people breathing in the same space. But a high reading is a pretty good red flag, and in any case suggests the air is bad for people's health. A well-functioning climate control system should kick in and ventilate. If it doesn't, something is wrong.

Which brings me to my proposal. Personal CO2 monitors are not expensive: I bought one on Amazon for $125. If enough people had them (perhaps with the aid of targeted subsidies), and if someone in the tech world created an app to collect and aggregate the readings, we could have a regularly refreshed database of the CO2 levels in every significant building. It could even be integrated with Google maps, so people could quickly and easily check whether a building was safe to enter.

Such an innovation would give building managers a huge incentive to stay on top of air quality. People could feel more comfortable going to work, sending their kids to school, going out to eat. The confidence would help the economy recover. So it's over to you, wizards of the internet of things. This is a tech project that could actually solve a problem.

This column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.

Cathy O'Neil is a Bloomberg Opinion columnist. She is a mathematician who has worked as a professor, hedge-fund analyst and data scientist. She founded ORCAA, an algorithmic auditing company, and is the author of “Weapons of Math Destruction.”

©2020 Bloomberg L.P.