What EPA's radon map says about Lancaster County

EPA's own radon map rates Lancaster County zone 3 - low potential, predicting a county-wide average indoor level below 2 pCi/L. Lancaster County sits at the 8th percentile nationally for radon potential — above 8 of every 100 rated counties.

Where Lancaster County sits nationally

About 11,062 people live in Lancaster County, Virginia, spread over 133.325 square miles. Population density there runs about 83 people per square mile. Among counties sharing Lancaster County's EPA zone, it outranks 23% of them by population. EPA's geology-based Region 3 groups Lancaster County with 244 other counties nationally sharing its underlying rock and soil profile.

What this actually means for a house in Lancaster County

Well clear of both the 1.3 pCi/L national indoor average and EPA's 4 pCi/L action level, Lancaster County's Zone 3 prediction is the low end of the scale. Don't read Zone 3 as a pass for Lancaster County — EPA's guidance to test every home makes no exception for counties predicted low.

If Lancaster County tests above the action level

Mitigation cost doesn't depend on Lancaster 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

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

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