Buying a (relatively expensive) CO2 monitor is one of those purchases that I was pensive about at first, but have zero regrets about a few years later. I was ignorant of a lot of things related to air quality, CO2 in particular. We were foolishly running a gas stove in a house with no ventilation, which probably had us up in the 1500+ range every time. This may seem like an obvious no-no to most of you but it was not a lesson we had ever learned.

You also get to see some other interesting observations, like how local construction digging up dirt on your street can cause elevated radon levels for months on end.

Can I ask what product you chose?