radon levels missouri

https://radonreductionstcharleshaven.clearhavendigest.com/posts/understanding-radon-reduction-in-st.-charles-what-every-homeowner-should-know

Radon levels in Missouri are a serious concern because the state sits on granite and limestone deposits that naturally release this radioactive gas, and the geology of the Ozarks and northern plains can cause high indoor concentrations, especially in basements and crawl spaces, with the EPA estimating that roughly one in five Missouri homes may exceed the safe action level, making testing the only way for residents to know their risk.