What EPA's radon map says about Miami-Dade County

Miami-Dade County is mapped as Zone 2 - Moderate Potential by EPA — meaning the county-wide average indoor level is predicted between 2 and 4 pCi/L. Nationally, Miami-Dade County ranks higher in radon potential than 66% of rated counties (the 66th percentile).

Where Miami-Dade County sits nationally

About 2,838,461 people live in Miami-Dade County, Florida, spread over 1,899.988 square miles. Population density there runs about 1,494 people per square mile. Among counties sharing Miami-Dade County's EPA zone, it outranks 100% of them by population. Miami-Dade County falls in EPA Radon Region 4, one of 736 counties nationally EPA assigns to that same geologic province.

Why the zone isn't the answer by itself

Miami-Dade County's Zone 2 prediction clears the 1.3 pCi/L national indoor average without reaching EPA's own 4 pCi/L point for recommending a fix. A Zone 2 rating is a moderate county-wide average, not a guarantee about any one house in Miami-Dade County — testing is the only way to know an individual home's actual level.

Next steps for a home in Miami-Dade County

Mitigation cost doesn't depend on Miami-Dade 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

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

More on how this number was built

Every figure on this page traces to EPA's own Map of Radon Zones and Census data, documented in the methodology guide. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.