My house is 56 years old. I'm guessing the kitchen upgrade is at least 5 years old. The carpet is probably at least a 5 years old. There isn't much fresh paint in here.
Am I about right to assume I probably don't have much in the way off off-gassing from anything in here, or does carpet / furniture / melamine continually off-gas for it's entire life?
Anyway, I've got some idea that CO2 buildup is a thing, and humidity, and off-gassing, so... I tend to ventilate the house frequently even during winter. Even when it's -5 outside, I'll occasionally open one or more windows / doors and turn the kitchen exhaust fan on in order to draw fresh air in and across the house. I'll also occasionally open multiple doors / windows for 10 minutes or so in an effort to replace the majority of the air in the house.
I tend to eschew yet-another-device that needs maintenance / power / charging / monitoring / fiddling because I tend to do a lot of that at work and would rather just come home and not-have-to-maintain-another-97-machines.
So I'm interested in the on average / sort of good enough / sometimes over-shoot-the-mark behavioural changes that would result if I did have air quality monitors.