Yuma County, AZ radon potential

EPA places Yuma 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. Yuma County sits at the 62nd percentile nationally for radon potential — above 62 of every 100 rated counties.

How Yuma County compares

Yuma County, Arizona is home to about 220,310 people across 5,513.82 square miles. That works out to roughly 40 people per square mile. Within its own EPA zone, Yuma County is bigger by population than 89% of the counties that share it. EPA's geology-based Region 9 groups Yuma County with 94 other counties nationally sharing its underlying rock and soil profile.

Zone vs. an actual test

EPA's Zone 2 rating for Yuma County sits below its own 4 pCi/L action level but above the national indoor average of about 1.3 pCi/L. A Zone 2 rating is a moderate county-wide average, not a guarantee about any one house in Yuma County — testing is the only way to know an individual home's actual level.

Testing and mitigation in Yuma County

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 Arizona's state radon program

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

Where Yuma County's figures come from

The methodology guide shows exactly which EPA and Census sources feed Yuma County's numbers. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.