radon gas test

https://theradonbasementnews.birchreport.com/posts/understanding-radon-in-basement-what-st.-louis-homeowners-need-to-know

We finally got around to doing a radon gas test in our basement, since we spend a lot of time down there and kept hearing about the health risks. The little detector sat on a shelf for about a week before we mailed it to the lab. It felt a little nerve-racking waiting for the results, but it's better to know than to wonder.