Shameless plug. We are maintaining an open source / open hardware indoor air quality project that measures CO2, PM2.5, temperature and humidity [1]. We use th

Shameless plug. We are maintaining an open source / open hardware indoor air quality project that measures CO2, PM2.5, temperature and humidity [1]. We use the same CO2 Sensor (Senseair S8) as the device in the article and I can confirm that it's very accurate. [1] https://www.airgradient.com/diy/ https://www.airgradient.com/diy/