What EPA's radon map says about Middlesex County

Middlesex 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 Middlesex County lands in the 8th percentile for radon potential.

Middlesex County by the numbers

About 10,949 people live in Middlesex County, Virginia, spread over 130.328 square miles. That works out to roughly 84 people per square mile. Among counties sharing Middlesex County's EPA zone, it outranks 23% of them by population. Middlesex County falls in EPA Radon Region 3, one of 245 counties nationally EPA assigns to that same geologic province.

Why the zone isn't the answer by itself

A Zone 3 county like Middlesex County is predicted closer to the 0.4 pCi/L typical outdoors than to EPA's 4 pCi/L action level. A Zone 3 label describes Middlesex County's average, not any one basement or slab in it — testing is still the only way an individual homeowner actually finds out.

Testing and mitigation in Middlesex County

Mitigation cost doesn't depend on Middlesex 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 Virginia's state radon program

Middlesex County's test kit answers today; a Airthings radon monitor keeps answering for Middlesex 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 Middlesex County's numbers. Whatever zone Middlesex County carries, the zone explainer covers what it does and doesn't tell you about any one house.