What EPA's radon map says about Preston County

Preston County is mapped as Zone 1 - Highest Potential by EPA — meaning the county-wide average indoor level is predicted above 4 pCi/L. Nationally that's the 86th percentile for radon potential — Preston County outranks 86% of every county EPA has rated.

Preston County by the numbers

About 34,055 people live in Preston County, West Virginia, spread over 648.814 square miles. Population density there runs about 52 people per square mile. Among counties sharing Preston County's EPA zone, it outranks 59% of them by population. EPA's geology-based Region 3 groups Preston County with 244 other counties nationally sharing its underlying rock and soil profile.

Zone vs. an actual test

Fixing a home becomes an EPA recommendation past 4 pCi/L, and that is precisely the side of the line Preston County's Zone 1 prediction lands on, well above the roughly 1.3 pCi/L most US homes average. EPA's guidance doesn't change because of a Zone 1 label: test the house. What changes is the reason to not put it off in Preston County specifically.

Next steps for a home in Preston County

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

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