Middlesex County, NJ Radon Zone Data

Middlesex County, NJ: EPA's radon zone, explained

EPA places Middlesex County in Zone 2 - Moderate Potential — a predicted county-wide average indoor radon level between 2 and 4 pCi/L, based on the geology, soil and aerial radioactivity data behind EPA's national map. Nationally, Middlesex County ranks higher in radon potential than 65% of rated counties (the 65th percentile).

Where Middlesex County sits nationally

Middlesex County, New Jersey is home to about 890,119 people across 309.313 square miles. That works out to roughly 2,878 people per square mile. By population, Middlesex County is the 23rd largest of every county sharing its EPA zone — the 98th percentile by population within that zone. Middlesex County falls in EPA Radon Region 2, one of 83 counties nationally EPA assigns to that same geologic province.

What this actually means for a house in Middlesex County

Middlesex County's Zone 2 prediction clears the 1.3 pCi/L national indoor average without reaching EPA's own 4 pCi/L point for recommending a fix. A Zone 2 rating is a moderate county-wide average, not a guarantee about any one house in Middlesex County — testing is the only way to know an individual home's actual level.

If Middlesex County tests above the action level

For a Middlesex 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 Jersey's state radon program

For Middlesex County, an ongoing number beats a one-time test - a Airthings radon monitor tracks Middlesex 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 Middlesex 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. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.