Tulare County, CA: EPA's radon zone, explained

Tulare 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, Tulare County ranks higher in radon potential than 64% of rated counties (the 64th percentile).

Tulare County by the numbers

Tulare County, California is home to about 483,546 people across 4,823.9 square miles. Population density there runs about 100 people per square mile. By population, Tulare County is the 53rd largest of every county sharing its EPA zone — the 95th percentile by population within that zone. Geologically, Tulare County is grouped into EPA Region 9 alongside 94 other counties that share its rock and soil setting.

What this actually means for a house in Tulare County

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

Next steps for a home in Tulare County

For a Tulare 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 California's state radon program

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

Where Tulare County's figures come from

Tulare County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.