Crawlspace air is bad.
The crawlspace and the living space make up the home you live in. You can’t have one part of your home sick, and another part healthy. You can’t rationalize you never go in the crawlspace, so you aren’t affected by it. Your crawlspace and living space share the same air. In fact 40 to 60% of the air you breathe is generated from your crawlspace. We consider your crawlspace the first floor of your home.