Carson City, NV: EPA's radon zone, explained

Carson City is mapped as Zone 1 - Highest Potential by EPA — meaning the county-wide average indoor level is predicted above 4 pCi/L. Carson City sits at the 91st percentile nationally for radon potential — above 91 of every 100 rated counties.

How Carson City compares

Carson City, Nevada is home to about 58,148 people across 144.534 square miles. Population density there runs about 402 people per square mile. By population, Carson City is the 283rd largest of every county sharing its EPA zone — the 73rd percentile by population within that zone. Geologically, Carson City 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 Carson City

Outdoor air nationally averages about 0.4 pCi/L, indoor air about 1.3 pCi/L — Carson City's Zone 1 prediction clears both of those and EPA's fix-it threshold besides. Being in Zone 1 raises the odds Carson City homes test above the action level, but it does not mean any specific house does — EPA recommends every home be tested, in every zone, because the only way to know is to test.

If Carson City tests above the action level

For a Carson City 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 Nevada's state radon program

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

Where Carson City's figures come from

The methodology guide shows exactly which EPA and Census sources feed Carson City's numbers. The guide to what a radon zone actually means covers why testing matters in every zone, not just Zone 1.