Radon levels in Missouri

Verified county-level radon indicators are available for 115 Missouri counties. Select a county for its source period and sample details.

High results are most common in Atchison County (70%) and least common in Vernon County (9%)Share of tests at or above 4 pCi/L by county · Radon test results from laboratories, 2008–2017 · 115 of 115 counties have data
Adair County: 27% of tests at or above 4 pCi/L · 92 testsAndrew County: 61% of tests at or above 4 pCi/L · 158 testsAtchison County: 70% of tests at or above 4 pCi/L · 103 testsAudrain County: 30% of tests at or above 4 pCi/L · 127 testsBarry County: 42% of tests at or above 4 pCi/L · 55 testsBarton County: 17% of tests at or above 4 pCi/L · 24 testsBates County: 26% of tests at or above 4 pCi/L · 23 testsBenton County: 31% of tests at or above 4 pCi/L · 49 testsBollinger County: 0% of tests at or above 4 pCi/L · 6 testsBoone County: 22% of tests at or above 4 pCi/L · 4,767 testsBuchanan County: 53% of tests at or above 4 pCi/L · 575 testsButler County: 21% of tests at or above 4 pCi/L · 33 testsCaldwell County: 6% of tests at or above 4 pCi/L · 16 testsCallaway County: 27% of tests at or above 4 pCi/L · 192 testsCamden County: 23% of tests at or above 4 pCi/L · 763 testsCape Girardeau County: 35% of tests at or above 4 pCi/L · 253 testsCarroll County: 33% of tests at or above 4 pCi/L · 18 testsCarter County: 25% of tests at or above 4 pCi/L · 4 testsCass County: 46% of tests at or above 4 pCi/L · 988 testsCedar County: 5% of tests at or above 4 pCi/L · 20 testsChariton County: 13% of tests at or above 4 pCi/L · 15 testsChristian County: 32% of tests at or above 4 pCi/L · 436 testsClark County: 29% of tests at or above 4 pCi/L · 17 testsClay County: 39% of tests at or above 4 pCi/L · 3,438 testsClinton County: 38% of tests at or above 4 pCi/L · 105 testsCole County: 25% of tests at or above 4 pCi/L · 768 testsCooper County: 41% of tests at or above 4 pCi/L · 90 testsCrawford County: 15% of tests at or above 4 pCi/L · 34 testsDade County: 0% of tests at or above 4 pCi/L · 7 testsDallas County: 15% of tests at or above 4 pCi/L · 27 testsDaviess County: 27% of tests at or above 4 pCi/L · 30 testsDeKalb County: 24% of tests at or above 4 pCi/L · 33 testsDent County: 36% of tests at or above 4 pCi/L · 14 testsDouglas County: 0% of tests at or above 4 pCi/L · 3 testsDunklin County: 6% of tests at or above 4 pCi/L · 16 testsFranklin County: 33% of tests at or above 4 pCi/L · 753 testsGasconade County: 32% of tests at or above 4 pCi/L · 44 testsGentry County: 42% of tests at or above 4 pCi/L · 24 testsGreene County: 33% of tests at or above 4 pCi/L · 1,470 testsGrundy County: 37% of tests at or above 4 pCi/L · 27 testsHarrison County: 29% of tests at or above 4 pCi/L · 24 testsHenry County: 38% of tests at or above 4 pCi/L · 81 testsHickory County: 0% of tests at or above 4 pCi/L · 9 testsHolt County: 62% of tests at or above 4 pCi/L · 29 testsHoward County: 44% of tests at or above 4 pCi/L · 62 testsHowell County: 46% of tests at or above 4 pCi/L · 138 testsIron County: 50% of tests at or above 4 pCi/L · 14 testsJackson County: 41% of tests at or above 4 pCi/L · 6,618 testsJasper County: 29% of tests at or above 4 pCi/L · 251 testsJefferson County: 42% of tests at or above 4 pCi/L · 2,652 testsJohnson County: 26% of tests at or above 4 pCi/L · 264 testsKnox County: 0% of tests at or above 4 pCi/L · 10 testsLaclede County: 37% of tests at or above 4 pCi/L · 46 testsLafayette County: 47% of tests at or above 4 pCi/L · 184 testsLawrence County: 27% of tests at or above 4 pCi/L · 70 testsLewis County: 32% of tests at or above 4 pCi/L · 71 testsLincoln County: 34% of tests at or above 4 pCi/L · 444 testsLinn County: 19% of tests at or above 4 pCi/L · 37 testsLivingston County: 22% of tests at or above 4 pCi/L · 49 testsMcDonald County: 21% of tests at or above 4 pCi/L · 19 testsMacon County: 19% of tests at or above 4 pCi/L · 36 testsMadison County: 39% of tests at or above 4 pCi/L · 23 testsMaries County: 14% of tests at or above 4 pCi/L · 21 testsMarion County: 42% of tests at or above 4 pCi/L · 282 testsMercer County: 27% of tests at or above 4 pCi/L · 11 testsMiller County: 17% of tests at or above 4 pCi/L · 154 testsMississippi County: 0% of tests at or above 4 pCi/L · 4 testsMoniteau County: 25% of tests at or above 4 pCi/L · 68 testsMonroe County: 23% of tests at or above 4 pCi/L · 30 testsMontgomery County: 13% of tests at or above 4 pCi/L · 47 testsMorgan County: 21% of tests at or above 4 pCi/L · 123 testsNew Madrid County: 11% of tests at or above 4 pCi/L · 9 testsNewton County: 31% of tests at or above 4 pCi/L · 167 testsNodaway County: 34% of tests at or above 4 pCi/L · 225 testsOregon County: 33% of tests at or above 4 pCi/L · 3 testsOsage County: 15% of tests at or above 4 pCi/L · 52 testsOzark County: 50% of tests at or above 4 pCi/L · 4 testsPemiscot County: 0% of tests at or above 4 pCi/L · 5 testsPerry County: 38% of tests at or above 4 pCi/L · 82 testsPettis County: 38% of tests at or above 4 pCi/L · 132 testsPhelps County: 15% of tests at or above 4 pCi/L · 204 testsPike County: 40% of tests at or above 4 pCi/L · 35 testsPlatte County: 38% of tests at or above 4 pCi/L · 1,789 testsPolk County: 12% of tests at or above 4 pCi/L · 78 testsPulaski County: 19% of tests at or above 4 pCi/L · 107 testsPutnam County: 33% of tests at or above 4 pCi/L · 9 testsRalls County: 33% of tests at or above 4 pCi/L · 43 testsRandolph County: 17% of tests at or above 4 pCi/L · 58 testsRay County: 39% of tests at or above 4 pCi/L · 108 testsReynolds County: 33% of tests at or above 4 pCi/L · 3 testsRipley County: 30% of tests at or above 4 pCi/L · 10 testsSt. Charles County: 27% of tests at or above 4 pCi/L · 7,001 testsSt. Clair County: 8% of tests at or above 4 pCi/L · 13 testsSte. Genevieve County: 31% of tests at or above 4 pCi/L · 74 testsSt. Francois County: 41% of tests at or above 4 pCi/L · 146 testsSt. Louis County: 26% of tests at or above 4 pCi/L · 17,747 testsSaline County: 49% of tests at or above 4 pCi/L · 55 testsSchuyler County: 9% of tests at or above 4 pCi/L · 11 testsScotland County: 17% of tests at or above 4 pCi/L · 18 testsScott County: 29% of tests at or above 4 pCi/L · 51 testsShannon County: 26% of tests at or above 4 pCi/L · 19 testsShelby County: 24% of tests at or above 4 pCi/L · 29 testsStoddard County: 12% of tests at or above 4 pCi/L · 25 testsStone County: 42% of tests at or above 4 pCi/L · 137 testsSullivan County: 33% of tests at or above 4 pCi/L · 6 testsTaney County: 37% of tests at or above 4 pCi/L · 146 testsTexas County: 19% of tests at or above 4 pCi/L · 57 testsVernon County: 9% of tests at or above 4 pCi/L · 34 testsWarren County: 37% of tests at or above 4 pCi/L · 285 testsWashington County: 26% of tests at or above 4 pCi/L · 38 testsWayne County: 24% of tests at or above 4 pCi/L · 17 testsWebster County: 20% of tests at or above 4 pCi/L · 103 testsWorth County: 9% of tests at or above 4 pCi/L · 11 testsWright County: 28% of tests at or above 4 pCi/L · 18 testsSt. Louis city: 17% of tests at or above 4 pCi/L · 1,873 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
Adair County9227%1.8Zone 2Radon test results from laboratories through 2017
Andrew County15861%4.9Zone 1Radon test results from laboratories through 2017
Atchison County10370%5.6Zone 1Radon test results from laboratories through 2017
Audrain County12730%2.5Zone 2Radon test results from laboratories through 2017
Barry County5542%3.1Zone 2Radon test results from laboratories through 2017
Barton County2417%1.4Zone 2Radon test results from laboratories through 2017
Bates County2326%1.5Zone 2Radon test results from laboratories through 2017
Benton County4931%2.0Zone 2Radon test results from laboratories through 2017
Bollinger County60%1.4Zone 2Radon test results from laboratories through 2017
Boone County4,76722%1.9Zone 2Radon test results from laboratories through 2017
Buchanan County57553%4.2Zone 1Radon test results from laboratories through 2017
Butler County3321%1.9Zone 3Radon test results from laboratories through 2017
Caldwell County166%1.5Zone 2Radon test results from laboratories through 2017
Callaway County19227%1.7Zone 2Radon test results from laboratories through 2017
Camden County76323%2.2Zone 2Radon test results from laboratories through 2017
Cape Girardeau County25335%2.8Zone 2Radon test results from laboratories through 2017
Carroll County1833%2.7Zone 2Radon test results from laboratories through 2017
Carter County425%2.8Zone 2Radon test results from laboratories through 2017
Cass County98846%3.5Zone 1Radon test results from laboratories through 2017
Cedar County205%1.3Zone 2Radon test results from laboratories through 2017
Chariton County1513%1.7Zone 2Radon test results from laboratories through 2017
Christian County43632%1.9Zone 2Radon test results from laboratories through 2017
Clark County1729%2.2Zone 2Radon test results from laboratories through 2017
Clay County3,43839%3.1Zone 1Radon test results from laboratories through 2017
Clinton County10538%2.8Zone 1Radon test results from laboratories through 2017
Cole County76825%2.1Zone 2Radon test results from laboratories through 2017
Cooper County9041%2.6Zone 2Radon test results from laboratories through 2017
Crawford County3415%1.5Zone 2Radon test results from laboratories through 2017
Dade County70%1.3Zone 2Radon test results from laboratories through 2017
Dallas County2715%1.4Zone 2Radon test results from laboratories through 2017
Daviess County3027%2.0Zone 2Radon test results from laboratories through 2017
DeKalb County3324%2.3Zone 2Radon test results from laboratories through 2017
Dent County1436%3.0Zone 2Radon test results from laboratories through 2017
Douglas County30%1.2Zone 2Radon test results from laboratories through 2017
Dunklin County166%1.3Zone 3Radon test results from laboratories through 2017
Franklin County75333%2.6Zone 2Radon test results from laboratories through 2017
Gasconade County4432%2.3Zone 2Radon test results from laboratories through 2017
Gentry County2442%3.5Zone 2Radon test results from laboratories through 2017
Greene County1,47033%2.5Zone 2Radon test results from laboratories through 2017
Grundy County2737%2.8Zone 2Radon test results from laboratories through 2017
Harrison County2429%1.9Zone 2Radon test results from laboratories through 2017
Henry County8138%3.4Zone 2Radon test results from laboratories through 2017
Hickory County90%2.0Zone 2Radon test results from laboratories through 2017
Holt County2962%4.9Zone 1Radon test results from laboratories through 2017
Howard County6244%3.5Zone 2Radon test results from laboratories through 2017
Howell County13846%3.5Zone 2Radon test results from laboratories through 2017
Iron County1450%3.5Zone 1Radon test results from laboratories through 2017
Jackson County6,61841%3.1Zone 1Radon test results from laboratories through 2017
Jasper County25129%2.0Zone 2Radon test results from laboratories through 2017
Jefferson County2,65242%3.1Zone 2Radon test results from laboratories through 2017
Johnson County26426%1.9Zone 2Radon test results from laboratories through 2017
Knox County100%1.9Zone 2Radon test results from laboratories through 2017
Laclede County4637%2.3Zone 2Radon test results from laboratories through 2017
Lafayette County18447%3.5Zone 2Radon test results from laboratories through 2017
Lawrence County7027%1.8Zone 2Radon test results from laboratories through 2017
Lewis County7132%2.6Zone 2Radon test results from laboratories through 2017
Lincoln County44434%2.2Zone 2Radon test results from laboratories through 2017
Linn County3719%1.8Zone 2Radon test results from laboratories through 2017
Livingston County4922%2.1Zone 2Radon test results from laboratories through 2017
Macon County3619%1.7Zone 2Radon test results from laboratories through 2017
Madison County2339%3.5Zone 2Radon test results from laboratories through 2017
Maries County2114%1.8Zone 2Radon test results from laboratories through 2017
Marion County28242%3.2Zone 2Radon test results from laboratories through 2017
McDonald County1921%1.9Zone 2Radon test results from laboratories through 2017
Mercer County1127%1.7Zone 2Radon test results from laboratories through 2017
Miller County15417%1.9Zone 2Radon test results from laboratories through 2017
Mississippi County40%0.1Zone 3Radon test results from laboratories through 2017
Moniteau County6825%2.2Zone 2Radon test results from laboratories through 2017
Monroe County3023%1.5Zone 2Radon test results from laboratories through 2017
Montgomery County4713%1.6Zone 2Radon test results from laboratories through 2017
Morgan County12321%2.2Zone 2Radon test results from laboratories through 2017
New Madrid County911%1.4Zone 3Radon test results from laboratories through 2017
Newton County16731%2.5Zone 2Radon test results from laboratories through 2017
Nodaway County22534%2.7Zone 1Radon test results from laboratories through 2017
Oregon County333%2.0Zone 2Radon test results from laboratories through 2017
Osage County5215%1.5Zone 2Radon test results from laboratories through 2017
Ozark County450%4.7Zone 2Radon test results from laboratories through 2017
Pemiscot County50%0.8Zone 3Radon test results from laboratories through 2017
Perry County8238%3.2Zone 2Radon test results from laboratories through 2017
Pettis County13238%2.8Zone 2Radon test results from laboratories through 2017
Phelps County20415%1.5Zone 2Radon test results from laboratories through 2017
Pike County3540%2.9Zone 2Radon test results from laboratories through 2017
Platte County1,78938%3.0Zone 1Radon test results from laboratories through 2017
Polk County7812%1.6Zone 2Radon test results from laboratories through 2017
Pulaski County10719%1.3Zone 2Radon test results from laboratories through 2017
Putnam County933%1.8Zone 2Radon test results from laboratories through 2017
Ralls County4333%2.7Zone 2Radon test results from laboratories through 2017
Randolph County5817%1.8Zone 2Radon test results from laboratories through 2017
Ray County10839%2.5Zone 2Radon test results from laboratories through 2017
Reynolds County333%2.2Zone 2Radon test results from laboratories through 2017
Ripley County1030%3.0Zone 2Radon test results from laboratories through 2017
Saline County5549%3.7Zone 2Radon test results from laboratories through 2017
Schuyler County119%1.0Zone 2Radon test results from laboratories through 2017
Scotland County1817%1.4Zone 2Radon test results from laboratories through 2017
Scott County5129%2.2Zone 3Radon test results from laboratories through 2017
Shannon County1926%1.3Zone 2Radon test results from laboratories through 2017
Shelby County2924%1.7Zone 2Radon test results from laboratories through 2017
St. Charles County7,00127%2.2Zone 2Radon test results from laboratories through 2017
St. Clair County138%1.5Zone 2Radon test results from laboratories through 2017
St. Francois County14641%2.9Zone 2Radon test results from laboratories through 2017
St. Louis city1,87317%1.9Zone 2Radon test results from laboratories through 2017
St. Louis County17,74726%2.3Zone 2Radon test results from laboratories through 2017
Ste. Genevieve County7431%2.5Zone 2Radon test results from laboratories through 2017
Stoddard County2512%1.1Zone 3Radon test results from laboratories through 2017
Stone County13742%2.9Zone 2Radon test results from laboratories through 2017
Sullivan County633%1.4Zone 2Radon test results from laboratories through 2017
Taney County14637%3.0Zone 2Radon test results from laboratories through 2017
Texas County5719%1.3Zone 2Radon test results from laboratories through 2017
Vernon County349%0.9Zone 2Radon test results from laboratories through 2017
Warren County28537%2.7Zone 2Radon test results from laboratories through 2017
Washington County3826%1.5Zone 2Radon test results from laboratories through 2017
Wayne County1724%1.9Zone 2Radon test results from laboratories through 2017
Webster County10320%1.6Zone 2Radon test results from laboratories through 2017
Worth County119%1.5Zone 2Radon test results from laboratories through 2017
Wright County1828%2.7Zone 2Radon test results from laboratories through 2017

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