radon in basement 4

https://radonhomebuyerslab.terracolumn.com/posts/a-practical-guide-to-radon-for-home-buyers-in-st.-charles-county

Radon in the basement is a silent worry for many homeowners because this radioactive gas seeps up from the soil without any smell or color, often getting trapped in lower levels. Testing is the only way to know if levels are dangerous, and if they are, fixing it usually involves sealing cracks and improving ventilation. It's one of those things you don't think about until you hear about a neighbor's high test result, then suddenly it feels urgent.