radon retest

https://myradongasrisksite.clearminster.com/posts/understanding-radon-gas-risk-in-st.-charles-county-homes

So you tested your home for radon and got a high reading. Now you're looking at a radon retest, which is simply doing the test again after you've installed a mitigation system. It's really the only way to know if that system is actually working to lower the gas levels in your house. The process is exactly the same as the first test—you set out a kit, leave it for a few days, and send it to a lab. But the results matter a lot more this time, because they tell you if your investment in radon redu…