I purchased a carbon dioxide monitoring device from Amazon recently. It was relatively affordable, about $100. It has a colour LED display which shows the CO2 reading in ppm, the temperature, and humidity. It also connects to wifi and it logs all the data it collects into an app I have on my tablet.
I purchased this device because I’ve been curious about the air quality in my apartment since I spend so much time at home now. I previously bought a device that measures the particulates in the air, as in how polluted or clean the air is. That device will tell you if the air is bad from say, forest fires, which has been common here in British Columbia in years past. The CO2 meter is a compliment to that and I guess it measures how “stuffy” the air is.
The good news is that the air in my apartment is generally very clean and very fresh. The CO2 meter is almost always below 500 ppm. Another good thing about this meter is that it is very portable, so it’s useful to bring on a trip, to measure how fresh the air is in a hotel for example. It also has an audible alarm that will ring if the CO2 level increases past a certain threshold. This is obviously useful for instances where high CO2 levels could be dangerous.
I encourage you to investigate if such a device could be useful for you.