Carroll County, MO radon potential

EPA places Carroll 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. Rank it against the rest of the country and Carroll County lands in the 39th percentile for radon potential.

Carroll County by the numbers

Carroll County, Missouri is home to about 8,414 people across 694.622 square miles. Population density there runs about 12 people per square mile. Within its own EPA zone, Carroll County is bigger by population than 17% of the counties that share it. EPA's geology-based Region 7 groups Carroll County with 411 other counties nationally sharing its underlying rock and soil profile.

What this actually means for a house in Carroll County

Neither at the 4 pCi/L action level nor down at the roughly 1.3 pCi/L national indoor norm, Carroll County's Zone 2 prediction lands in the gap between the two. A county-wide moderate average, like Carroll County's, can still hide a specific house well above or below it — testing is what actually answers the question.

If Carroll 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 Missouri's state radon program

For Carroll County, an ongoing number beats a one-time test - a Airthings radon monitor tracks Carroll 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 Carroll County's figures come from

Carroll County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. The guide to what a radon zone actually means covers why testing matters in every zone, not just Zone 1.