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

EPA's own radon map rates Chowan County zone 3 - low potential, predicting a county-wide average indoor level below 2 pCi/L. Nationally, Chowan County ranks higher in radon potential than 10% of rated counties (the 10th percentile).

Chowan County by the numbers

Chowan County, North Carolina is home to about 13,891 people across 172.657 square miles. Averaged across its land area, Chowan County runs about 80 people per square mile. By population, Chowan County is the 732nd largest of every county sharing its EPA zone — the 29th percentile by population within that zone. Geologically, Chowan 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 Chowan County

At Zone 3, Chowan County's predicted county average is under the national indoor average (~1.3 pCi/L) and well below EPA's 4 pCi/L action level — outdoor air nationally runs about 0.4 pCi/L for comparison. A Zone 3 label describes Chowan County's average, not any one basement or slab in it — testing is still the only way an individual homeowner actually finds out.

If Chowan County tests above the action level

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

Where Chowan County's figures come from

Chowan 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.