Monitoring CO2 Levels in Apartment or Car

Inspiration for this project was Makezine article and blog post "Fresh Air" and Adafruit's SCD-30 sensor page.

A lot of interest in indoor CO2 monitoring was sparked by a professor that built a CO2 monitor for his classroom. He found that the CO2 levels at the end of class were enough to make you groggy/sleepy and therefore not able to learn as well.

In my experimentation, an interesting discovery was the elevation of CO2 levels in a short drive with the windows up. My car, a Nissan Sentra, approached 2000 ppm in a one-person 30-minute commute. Having one window down @55 mph (90 kph) for a minute brought the levels back to below 1000 ppm.