Is Power County, ID a radon risk area?

EPA's own radon map rates Power County zone 2 - moderate potential, predicting a county-wide average indoor level between 2 and 4 pCi/L. Nationally that's the 38th percentile for radon potential — Power County outranks 38% of every county EPA has rated.

Where Power County sits nationally

About 8,381 people live in Power County, Idaho, spread over 1,403.826 square miles. Population density there runs about 6 people per square mile. Rank 861 by population within its EPA zone puts Power County at the 17th percentile among zone peers. Power County falls in EPA Radon Region 10, one of 142 counties nationally EPA assigns to that same geologic province.

Why the zone isn't the answer by itself

Call it a middle case: above the 1.3 pCi/L most US homes average, below the 4 pCi/L line EPA uses to recommend mitigation — that's Power County's Zone 2 prediction. Power County's Zone 2 rating sits in the middle nationally; EPA's guidance is unchanged by that — test every home regardless of its zone.

If Power County tests above the action level

Nothing about Power County's EPA zone changes the mitigation number: $800–$2,500 nationally (around $1,200 typical), set by the house's foundation rather than the county it sits in — and only relevant once a test actually clears 4 pCi/L.

Find Idaho's state radon program

Power County's test kit answers today; a Airthings radon monitor keeps answering for Power County over time. Affiliate link, RadonZoneCheck earns a commission there, at no extra cost to you. Code RADONZONE-10OFF takes 10% off at checkout.

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. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.