Hampshire County, MA Radon Zone Data

Hampshire County, MA: EPA's radon zone, explained

Hampshire County is mapped as Zone 2 - Moderate Potential by EPA — meaning the county-wide average indoor level is predicted between 2 and 4 pCi/L. That puts Hampshire County in the 61st percentile nationally for radon potential — higher than 61% of the counties EPA has rated.

Where Hampshire County sits nationally

Hampshire County, Massachusetts is home to about 165,399 people across 527.236 square miles. Population density there runs about 314 people per square mile. By population, Hampshire County is the 142nd largest of every county sharing its EPA zone — the 86th percentile by population within that zone. Geologically, Hampshire County is grouped into EPA Region 1 alongside 58 other counties that share its rock and soil setting.

Why the zone isn't the answer by itself

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

If Hampshire County tests above the action level

For a Hampshire 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 Massachusetts's state radon program

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

Where Hampshire County's figures come from

Hampshire County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. Whatever zone Hampshire County carries, the zone explainer covers what it does and doesn't tell you about any one house.