What EPA's radon map says about Holmes County

EPA's own radon map rates Holmes County zone 3 - low potential, predicting a county-wide average indoor level below 2 pCi/L. That puts Holmes County in the 13th percentile nationally for radon potential — higher than 13% of the counties EPA has rated.

How Holmes County compares

About 19,876 people live in Holmes County, Florida, spread over 478.858 square miles. That works out to roughly 42 people per square mile. Among counties sharing Holmes County's EPA zone, it outranks 40% of them by population. Holmes 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 Holmes County is predicted closer to the 0.4 pCi/L typical outdoors than to EPA's 4 pCi/L action level. A Zone 3 rating means Holmes 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 Holmes County tests above the action level

Mitigation cost doesn't depend on Holmes 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

Holmes County's test kit answers today; a Airthings radon monitor keeps answering for Holmes 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

The methodology guide shows exactly which EPA and Census sources feed Holmes County's numbers. Whatever zone Holmes County carries, the zone explainer covers what it does and doesn't tell you about any one house.