Radon levels in Delaware

Verified county-level radon indicators are available for 3 Delaware counties. Select a county for its source period and sample details.

High results are most common in New Castle County (17%) and least common in Sussex County (10%)Share of tests at or above 4 pCi/L by county · Radon test results from laboratories, 2008–2017 · 3 of 3 counties have data
Kent County: 17% of tests at or above 4 pCi/L · 1,516 testsNew Castle County: 17% of tests at or above 4 pCi/L · 10,247 testsSussex County: 10% of tests at or above 4 pCi/L · 451 tests
  • Under 10%
  • 10–20%
  • 20–30%
  • 30–40%
  • 40% or more
  • No data

Counties

CountyTests% ≥ 4 pCi/LMedian (pCi/L)EPA zone (1993)Source
Kent County1,51617%1.6Zone 3Radon test results from laboratories through 2017
New Castle County10,24717%1.8Zone 2Radon test results from laboratories through 2017
Sussex County45110%1.0Zone 3Radon test results from laboratories through 2017

Test your home

County figures show how often tests come back high, not the level in your home. Only a test tells you that: see how to test for radon.

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