Suffolk County, NY radon potential

EPA's own radon map rates Suffolk County zone 3 - low potential, predicting a county-wide average indoor level below 2 pCi/L. That puts Suffolk County in the 32nd percentile nationally for radon potential — higher than 32% of the counties EPA has rated.

How Suffolk County compares

Suffolk County, New York is home to about 1,535,909 people across 910.94 square miles. Averaged across its land area, Suffolk County runs about 1,686 people per square mile. Within its own EPA zone, Suffolk County is bigger by population than 98% of the counties that share it. EPA's geology-based Region 2 groups Suffolk County with 82 other counties nationally sharing its underlying rock and soil profile.

Why the zone isn't the answer by itself

Suffolk County's Zone 3 prediction undercuts the roughly 1.3 pCi/L most US homes average, nowhere near EPA's 4 pCi/L threshold for recommending mitigation. A Zone 3 label describes Suffolk County's average, not any one basement or slab in it — testing is still the only way an individual homeowner actually finds out.

If Suffolk 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 New York's state radon program

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

Where Suffolk County's figures come from

The methodology guide shows exactly which EPA and Census sources feed Suffolk County's numbers. Whatever zone Suffolk County carries, the zone explainer covers what it does and doesn't tell you about any one house.