What EPA's radon map says about Sumter County

Sumter County is mapped as Zone 3 - Low Potential by EPA — meaning the county-wide average indoor level is predicted below 2 pCi/L. Rank it against the rest of the country and Sumter County lands in the 28th percentile for radon potential.

Where Sumter County sits nationally

About 154,693 people live in Sumter County, Florida, spread over 557.136 square miles. Population density there runs about 278 people per square mile. Among counties sharing Sumter County's EPA zone, it outranks 84% of them by population. Sumter County falls in EPA Radon Region 4, one of 736 counties nationally EPA assigns to that same geologic province.

Zone vs. an actual test

A Zone 3 county like Sumter County is predicted closer to the 0.4 pCi/L typical outdoors than to EPA's 4 pCi/L action level. Low doesn't mean zero: EPA's own data shows homes in Zone 3 counties like Sumter County testing above the action level often enough that skipping a test isn't the safe assumption.

Testing and mitigation in Sumter County

Mitigation cost doesn't depend on Sumter 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

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

More on how this number was built

Sumter County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. Whatever zone Sumter County carries, the zone explainer covers what it does and doesn't tell you about any one house.