Which Iowa Counties Have the Highest Radon? (CDC County Data)
Using radon tests reported to the CDC (2008–2017), here’s how Iowa counties compare — the highest-radon counties, the lowest, and why a below-average county still isn’t a safe one.
Original Iowa-focused radon content — geological deep dives, real estate transaction playbooks, regulatory explainers, contractor verification guides, and seasonal awareness articles. Each article cross-references authoritative sources (EPA, ALA, AARST, Iowa DEP/HHS) and is regularly updated to reflect current standards.
Using radon tests reported to the CDC (2008–2017), here’s how Iowa counties compare — the highest-radon counties, the lowest, and why a below-average county still isn’t a safe one.
Iowa pairs the nation's highest indoor-radon geology with heavy rural reliance on private wells — a double exposure path most national guides ignore. Here's what waterborne radon really means for Iowa homeowners.
January is National Radon Action Month — designated by the EPA, Surgeon General, and American Lung Association. In Iowa, where the average home has more than twice the EPA action level of radon, January is when you should test. Here are the free Iowa test kit programs + winter testing rationale.
Iowa real estate transactions where the buyer's inspection radon test returns above 4 pCi/L are routine — roughly 5 in 7 Iowa homes test elevated. Here's how the negotiation patterns actually break down, what each side typically pays, and how to keep the closing timeline intact.
Iowa's #1 indoor radon ranking is driven by four converging factors — uranium-bearing glacial till blanketing the state, fractured limestone bedrock in the Driftless Area, basement-heavy housing stock, and cold-winter stack-effect physics. Here's the geology + climate explainer.
While you're reading — if you've tested elevated, our partner contractors quote within 4 business hours. Free assessment, lender-acceptable documentation, NRPP + IDPH-certified.