Columbus County, NC Radon Zone Data

Columbus County, NC: EPA's radon zone, explained

EPA places Columbus County in Zone 3 - Low Potential — a predicted county-wide average indoor radon level below 2 pCi/L, based on the geology, soil and aerial radioactivity data behind EPA's national map. Nationally that's the 22nd percentile for radon potential — Columbus County outranks 22% of every county EPA has rated.

Where Columbus County sits nationally

Columbus County, North Carolina is home to about 50,054 people across 938.197 square miles. That works out to roughly 53 people per square mile. By population, Columbus County is the 346th largest of every county sharing its EPA zone — the 67th percentile by population within that zone. Geologically, Columbus County is grouped into EPA Region 4 alongside 735 other counties that share its rock and soil setting.

What this actually means for a house in Columbus County

Columbus County's predicted average sits below the national indoor average of about 1.3 pCi/L, well under EPA's 4 pCi/L action level. A Zone 3 label describes Columbus County's average, not any one basement or slab in it — testing is still the only way an individual homeowner actually finds out.

If Columbus County tests above the action level

For a Columbus 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 North Carolina's state radon program

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

Where Columbus 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. Whatever zone Columbus County carries, the zone explainer covers what it does and doesn't tell you about any one house.