Inyo County, CA radon potential

Inyo County is mapped as Zone 2 - Moderate Potential by EPA — meaning the county-wide average indoor level is predicted between 2 and 4 pCi/L. Nationally, Inyo County ranks higher in radon potential than 45% of rated counties (the 45th percentile).

Inyo County by the numbers

Inyo County, California is home to about 18,485 people across 10,197.261 square miles. That works out to roughly 2 people per square mile. Within its own EPA zone, Inyo County is bigger by population than 37% of the counties that share it. EPA's geology-based Region 9 groups Inyo County with 94 other counties nationally sharing its underlying rock and soil profile.

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 Inyo County's Zone 2 prediction. A Zone 2 rating is a moderate county-wide average, not a guarantee about any one house in Inyo County — testing is the only way to know an individual home's actual level.

If Inyo County tests above the action level

A short-term test kit is the standard first step and typically costs far less than mitigation itself. If a test comes back at or above 4 pCi/L, a radon mitigation system for a typical home runs roughly $800–$2,500 (around $1,200 for a common single-family install), driven mainly by foundation type, not by county.

Find California's state radon program

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

Where Inyo 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. The guide to what a radon zone actually means covers why testing matters in every zone, not just Zone 1.