What EPA's radon map says about Dorchester County

Dorchester County is mapped as Zone 3 - Low Potential by EPA — meaning the county-wide average indoor level is predicted below 2 pCi/L. Nationally that's the 18th percentile for radon potential — Dorchester County outranks 18% of every county EPA has rated.

Where Dorchester County sits nationally

About 33,138 people live in Dorchester County, Maryland, spread over 540.765 square miles. That works out to roughly 61 people per square mile. Among counties sharing Dorchester County's EPA zone, it outranks 56% of them by population. Dorchester 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 Dorchester 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 Dorchester 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.

Next steps for a home in Dorchester County

Mitigation cost doesn't depend on Dorchester 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 Maryland's state radon program

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

Every figure on this page traces to EPA's own Map of Radon Zones and Census data, documented in the methodology guide. Whatever zone Dorchester County carries, the zone explainer covers what it does and doesn't tell you about any one house.