Strafford County, NH: EPA's radon zone, explained
EPA's own radon map rates Strafford County zone 2 - moderate potential, predicting a county-wide average indoor level between 2 and 4 pCi/L. Rank it against the rest of the country and Strafford County lands in the 61st percentile for radon potential.
Where Strafford County sits nationally
Strafford County, New Hampshire is home to about 134,202 people across 367.479 square miles. Averaged across its land area, Strafford County runs about 365 people per square mile. By population, Strafford County is the 156th largest of every county sharing its EPA zone — the 85th percentile by population within that zone. Strafford County falls in EPA Radon Region 1, one of 59 counties nationally EPA assigns to that same geologic province.
What this actually means for a house in Strafford County
EPA's Zone 2 rating for Strafford County sits below its own 4 pCi/L action level but above the national indoor average of about 1.3 pCi/L. Middle-of-the-pack doesn't mean risk-free for any one Strafford County address — a moderate county average still leaves individual homes to test either side of it.
Next steps for a home in Strafford County
For a Strafford 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 New Hampshire's state radon program
For Strafford County, an ongoing number beats a one-time test - a Airthings radon monitor tracks Strafford 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 Strafford County's figures come from
Strafford County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. Whatever zone Strafford County carries, the zone explainer covers what it does and doesn't tell you about any one house.