Apache County, AZ: EPA's radon zone, explained

EPA places Apache County in Zone 2 - Moderate Potential — a predicted county-wide average indoor radon level between 2 and 4 pCi/L, based on the geology, soil and aerial radioactivity data behind EPA's national map. Rank it against the rest of the country and Apache County lands in the 57th percentile for radon potential.

Where Apache County sits nationally

Apache County, Arizona is home to about 64,800 people across 11,198.31 square miles. Population density there runs about 6 people per square mile. By population, Apache County is the 288th largest of every county sharing its EPA zone — the 72nd percentile by population within that zone. Geologically, Apache County is grouped into EPA Region 9 alongside 94 other counties that share its rock and soil setting.

Zone vs. an actual test

EPA's Zone 2 rating for Apache County sits below its own 4 pCi/L action level but above the national indoor average of about 1.3 pCi/L. Middle-of-the-pack doesn't mean risk-free for any one Apache County address — a moderate county average still leaves individual homes to test either side of it.

Testing and mitigation in Apache County

For a Apache County homeowner, the order is simple: test first, since a kit costs a small fraction of what mitigation would. Only if the result clears 4 pCi/L does a system — typically $800–$2,500, about $1,200 for a common install — become worth pricing out.

Find Arizona's state radon program

For Apache County, an ongoing number beats a one-time test - a Airthings radon monitor tracks Apache County's levels over time. RadonZoneCheck earns a commission there, at no extra cost to you. RADONZONE-10OFF at checkout knocks 10% off.

Where Apache County's figures come from

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