Yeah the thing we've casually called "stuffy air" forever is, essentially, 100% equivalent with high CO2 levels. There are some other situations where non-"stu

Yeah the thing we've casually called "stuffy air" forever is, essentially, 100% equivalent with high CO2 levels. There are some other situations where non-"stuffy" air might have too much CO2, I guess. I guess you could pump CO2 into a room with cool, dry air. But barring a contrived situation like that, stuffy=CO2.