What EPA's radon map says about Bay County

EPA's own radon map rates Bay County zone 3 - low potential, predicting a county-wide average indoor level below 2 pCi/L. That puts Bay County in the 29th percentile nationally for radon potential — higher than 29% of the counties EPA has rated.

Where Bay County sits nationally

About 199,718 people live in Bay County, Florida, spread over 758.62 square miles. That works out to roughly 263 people per square mile. Among counties sharing Bay County's EPA zone, it outranks 87% of them by population. EPA's geology-based Region 4 groups Bay County with 735 other counties nationally sharing its underlying rock and soil profile.

Why the zone isn't the answer by itself

At Zone 3, Bay County's predicted county average is under the national indoor average (~1.3 pCi/L) and well below EPA's 4 pCi/L action level — outdoor air nationally runs about 0.4 pCi/L for comparison. A Zone 3 rating means Bay County's county-wide average is predicted low, but EPA is explicit that a meaningful share of homes in low-potential zones still test above the action level — a low zone is not a reason to skip testing.

If Bay County tests above the action level

Mitigation cost doesn't depend on Bay County's zone — it depends on the house's foundation. A typical system runs $800–$2,500 (about $1,200 typical), and testing first is what tells you whether that's needed at all.

Find Florida's state radon program

Bay County's test kit answers today; a Airthings radon monitor keeps answering for Bay County over time. Affiliate link, RadonZoneCheck earns a commission there, at no extra cost to you. RADONZONE-10OFF at checkout knocks 10% off.

More on how this number was built

The methodology guide shows exactly which EPA and Census sources feed Bay County's numbers. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.