Kent County, DE: EPA's radon zone, explained

EPA's own radon map rates Kent County zone 3 - low potential, predicting a county-wide average indoor level below 2 pCi/L. Nationally that's the 29th percentile for radon potential — Kent County outranks 29% of every county EPA has rated.

Where Kent County sits nationally

Kent County, Delaware is home to about 192,690 people across 586.061 square miles. Averaged across its land area, Kent County runs about 329 people per square mile. By population, Kent County is the 136th largest of every county sharing its EPA zone — the 87th percentile by population within that zone. Geologically, Kent County is grouped into EPA Region 3 alongside 244 other counties that share its rock and soil setting.

Zone vs. an actual test

Well clear of both the 1.3 pCi/L national indoor average and EPA's 4 pCi/L action level, Kent County's Zone 3 prediction is the low end of the scale. A Zone 3 label describes Kent County's average, not any one basement or slab in it — testing is still the only way an individual homeowner actually finds out.

Next steps for a home in Kent County

For a Kent 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 Delaware's state radon program

For Kent County, an ongoing number beats a one-time test - a Airthings radon monitor tracks Kent 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 Kent County's figures come from

The methodology guide shows exactly which EPA and Census sources feed Kent County's numbers. The guide to what a radon zone actually means covers why testing matters in every zone, not just Zone 1.