Locations and reports
Radon Levels in Iowa
What this means for you
- Your area: EPA rates 99 of Iowa's 99 classified counties Zone 1, the highest of its three radon zones. Zones are predictions for whole counties, and homes with elevated levels occur in all three zones.
- Local tests: CDC publishes Iowa's radon test results by county. Open your county below to see its figures.
- Your home: The only way to know your home’s level is to test it.
pCi/L (picocuries per liter) is the unit radon is measured in. EPA recommends fixing a home at 4 pCi/L or above, its action level.
For Iowa, EPA's Map of Radon Zones places 99 of its 99 classified counties in Zone 1, highest predicted potential, a prediction for each county as a whole. Radon levels vary from home to home, so only a test measures the level in yours.
Predicted: EPA radon zone
99 of 99 counties classified
EPA classifies counties, not states. Of the 99 counties in Iowa with a zone, 99 are in Zone 1.
- Zone 1: Highest predicted potentialgreater than 4 pCi/L99 of 99 counties · 100.0%
An EPA radon zone describes predicted potential across a whole county. It is not intended to determine whether any individual home should be tested, and homes with elevated levels occur in all three zones. EPA recommends testing every home regardless of zone, and testing is the only way to know the radon level in a specific building.
This is a county-level geologic prediction. It is not a measurement of any address, and houses with elevated radon are found in all three zones.
Predicted: EPA Map of Radon Zones
Measured: tests reported to CDC
CDC publishes Iowa's radon test figures by county: 99 of its 99 counties have one. Each county's share is in the county list.
Iowa, In figures
Iowa in figures
What the published data says about Iowa, in words. A zone and a share of tests describe an area, never the level in any one home.
Predicted
PredictedEPA places 99 of Iowa's 99 counties in Zone 1.
Zone 1 counties, A to Z, begin with Adair County, Adams County and Allamakee County; the county section below lists all 99.
Compared
Calculated by Radon411100% of Iowa's counties with a zone on file are in Zone 1, a larger share than across all U.S. counties (34%). It is a share of counties, not of land, people or homes.
Reported tests
MeasuredCDC has no statewide testing figure for Iowa on file here.
99 of the 99 counties have a published county figure; the most tests in each one's latest year were reported for Polk County (7,790 in 2017), Linn County (7,417 in 2017) and Johnson County (6,142 in 2017).
Local record
Iowa's radon program is the Iowa HHS Radon Program, run by Iowa Department of Health and Human Services; its contacts are under Local resources.
3 cities have a page setting the figures of the counties it lies in side by side: Ames, Iowa City and Waterloo.
Iowa, Counties
Iowa counties by EPA zone
PredictedAll 99 counties, by the zone EPA predicts for each. Every county has its own report.
Zone 1: highest predicted potential99
- Adair County72.4% of reported tests at or above 4 pCi/L, 2017
- Adams County65.4% of reported tests at or above 4 pCi/L, 2017
- Allamakee County73.2% of reported tests at or above 4 pCi/L, 2017
- Appanoose County45.3% of reported tests at or above 4 pCi/L, 2017
- Audubon County78.3% of reported tests at or above 4 pCi/L, 2017
- Benton County62.1% of reported tests at or above 4 pCi/L, 2017
- Black Hawk County48.4% of reported tests at or above 4 pCi/L, 2017
- Boone County68.7% of reported tests at or above 4 pCi/L, 2017
- Bremer County53.0% of reported tests at or above 4 pCi/L, 2017
- Buchanan County51.2% of reported tests at or above 4 pCi/L, 2017
- Buena Vista County72.1% of reported tests at or above 4 pCi/L, 2017
- Butler County59.9% of reported tests at or above 4 pCi/L, 2017
- Calhoun County69.8% of reported tests at or above 4 pCi/L, 2017
- Carroll County77.6% of reported tests at or above 4 pCi/L, 2017
- Cass County77.4% of reported tests at or above 4 pCi/L, 2017
- Cedar County60.4% of reported tests at or above 4 pCi/L, 2017
- Cerro Gordo County59.0% of reported tests at or above 4 pCi/L, 2017
- Cherokee County74.5% of reported tests at or above 4 pCi/L, 2017
- Chickasaw County59.0% of reported tests at or above 4 pCi/L, 2017
- Clarke County45.8% of reported tests at or above 4 pCi/L, 2017
- Clay County79.4% of reported tests at or above 4 pCi/L, 2017
- Clayton County62.6% of reported tests at or above 4 pCi/L, 2017
- Clinton County52.7% of reported tests at or above 4 pCi/L, 2017
- Crawford County74.8% of reported tests at or above 4 pCi/L, 2017
- Dallas County58.5% of reported tests at or above 4 pCi/L, 2017
- Davis County42.4% of reported tests at or above 4 pCi/L, 2017
- Decatur County25.9% of reported tests at or above 4 pCi/L, 2017
- Delaware County50.0% of reported tests at or above 4 pCi/L, 2017
- Des Moines County51.1% of reported tests at or above 4 pCi/L, 2017
- Dickinson County70.3% of reported tests at or above 4 pCi/L, 2017
- Dubuque County46.8% of reported tests at or above 4 pCi/L, 2017
- Emmet County71.0% of reported tests at or above 4 pCi/L, 2017
- Fayette County62.7% of reported tests at or above 4 pCi/L, 2017
- Floyd County59.5% of reported tests at or above 4 pCi/L, 2017
- Franklin County73.5% of reported tests at or above 4 pCi/L, 2017
- Fremont County69.8% of reported tests at or above 4 pCi/L, 2017
- Greene County71.3% of reported tests at or above 4 pCi/L, 2017
- Grundy County66.9% of reported tests at or above 4 pCi/L, 2017
- Guthrie County70.8% of reported tests at or above 4 pCi/L, 2017
- Hamilton County64.3% of reported tests at or above 4 pCi/L, 2017
- Hancock County64.5% of reported tests at or above 4 pCi/L, 2017
- Hardin County62.8% of reported tests at or above 4 pCi/L, 2017
- Harrison County69.8% of reported tests at or above 4 pCi/L, 2017
- Henry County46.4% of reported tests at or above 4 pCi/L, 2017
- Howard County61.3% of reported tests at or above 4 pCi/L, 2017
- Humboldt County70.1% of reported tests at or above 4 pCi/L, 2017
- Ida County71.7% of reported tests at or above 4 pCi/L, 2017
- Iowa County59.2% of reported tests at or above 4 pCi/L, 2017
- Jackson County52.7% of reported tests at or above 4 pCi/L, 2017
- Jasper County73.3% of reported tests at or above 4 pCi/L, 2017
- Jefferson County33.5% of reported tests at or above 4 pCi/L, 2017
- Johnson County41.6% of reported tests at or above 4 pCi/L, 2017
- Jones County59.3% of reported tests at or above 4 pCi/L, 2017
- Keokuk County60.3% of reported tests at or above 4 pCi/L, 2017
- Kossuth County66.1% of reported tests at or above 4 pCi/L, 2017
- Lee County43.6% of reported tests at or above 4 pCi/L, 2017
- Linn County39.7% of reported tests at or above 4 pCi/L, 2017
- Louisa County52.1% of reported tests at or above 4 pCi/L, 2017
- Lucas County39.3% of reported tests at or above 4 pCi/L, 2017
- Lyon County77.6% of reported tests at or above 4 pCi/L, 2017
- Madison County62.3% of reported tests at or above 4 pCi/L, 2017
- Mahaska County61.1% of reported tests at or above 4 pCi/L, 2017
- Marion County67.3% of reported tests at or above 4 pCi/L, 2017
- Marshall County70.2% of reported tests at or above 4 pCi/L, 2017
- Mills County70.1% of reported tests at or above 4 pCi/L, 2017
- Mitchell County70.7% of reported tests at or above 4 pCi/L, 2017
- Monona County74.6% of reported tests at or above 4 pCi/L, 2017
- Monroe County33.9% of reported tests at or above 4 pCi/L, 2017
- Montgomery County67.4% of reported tests at or above 4 pCi/L, 2017
- Muscatine County46.5% of reported tests at or above 4 pCi/L, 2017
- O'Brien County81.7% of reported tests at or above 4 pCi/L, 2017
- Osceola County67.2% of reported tests at or above 4 pCi/L, 2017
- Page County71.7% of reported tests at or above 4 pCi/L, 2017
- Palo Alto County70.8% of reported tests at or above 4 pCi/L, 2017
- Plymouth County82.3% of reported tests at or above 4 pCi/L, 2017
- Pocahontas County68.8% of reported tests at or above 4 pCi/L, 2017
- Polk County64.4% of reported tests at or above 4 pCi/L, 2017
- Pottawattamie County57.4% of reported tests at or above 4 pCi/L, 2017
- Poweshiek County70.6% of reported tests at or above 4 pCi/L, 2017
- Ringgold County28.7% of reported tests at or above 4 pCi/L, 2017
- Sac County76.6% of reported tests at or above 4 pCi/L, 2017
- Scott County44.3% of reported tests at or above 4 pCi/L, 2017
- Shelby County78.4% of reported tests at or above 4 pCi/L, 2017
- Sioux County84.2% of reported tests at or above 4 pCi/L, 2017
- Story County59.9% of reported tests at or above 4 pCi/L, 2017
- Tama County67.9% of reported tests at or above 4 pCi/L, 2017
- Taylor County60.9% of reported tests at or above 4 pCi/L, 2017
- Union County61.8% of reported tests at or above 4 pCi/L, 2017
- Van Buren County32.1% of reported tests at or above 4 pCi/L, 2017
- Wapello County35.9% of reported tests at or above 4 pCi/L, 2017
- Warren County66.0% of reported tests at or above 4 pCi/L, 2017
- Washington County54.9% of reported tests at or above 4 pCi/L, 2017
- Wayne County34.8% of reported tests at or above 4 pCi/L, 2017
- Webster County69.4% of reported tests at or above 4 pCi/L, 2017
- Winnebago County71.9% of reported tests at or above 4 pCi/L, 2017
- Winneshiek County66.4% of reported tests at or above 4 pCi/L, 2017
- Woodbury County69.2% of reported tests at or above 4 pCi/L, 2017
- Worth County67.5% of reported tests at or above 4 pCi/L, 2017
- Wright County66.8% of reported tests at or above 4 pCi/L, 2017
Iowa, Cities
Cities in Iowa with their own page
Radon data is published by county, not by city. Each city page sets the figures of the counties the city lies in side by side.
Iowa, Local resources
Local resources in Iowa
Who to ask in Iowa: the state's radon program, test kits and professionals.
Iowa HHS Radon Program
Iowa Department of Health and Human Services
Iowa’s radon program answers questions about testing, mitigation and the rules where you live.
- Phone
- (515) 281-4928
- Licensing of radon professionals
Iowa’s radon program approves applications for persons who wish to become certified to perform radon testing or credentialed to perform mitigation and laboratories that provide radon testing devices and analytical services.
- Disclosure when a home is sold or rented
However, per Iowa Code chapters 543B.9 and 543B.18 and Iowa Administrative Code 193E Chapter 14 administered by the Iowa Real Estate Commission, a seller must disclose any known tests for the presence of radon and if yes, provide the date of last report and the result(s).
Test kits
The program says: You can reach the Hotline by calling 1-800-383-5992 to order low-cost radon test kits and find answers to your radon questions.
Radon professionals
210 professionals are listed in Iowa.
Professionals in IowaIowa, Questions
Questions about radon in Iowa
Common questions9 questions, answered from the figures above
Is radon a problem in Iowa?
EPA's Map of Radon Zones places 99 of the 99 Iowa counties it classifies in Zone 1, the highest predicted potential, 0 in Zone 2 and 0 in Zone 3. An EPA radon zone describes predicted potential across a whole county. It is not intended to determine whether any individual home should be tested, and homes with elevated levels occur in all three zones. EPA recommends testing every home regardless of zone, and testing is the only way to know the radon level in a specific building.
Who does radon mitigation in Iowa?
Radon411's Iowa directory lists 210 certified radon companies. EPA recommends having a qualified contractor fix a home with a radon problem, because lowering high radon levels takes technical knowledge and special skills, and some states require the work to be done by a licensed or certified professional.
How radon mitigation worksWhat mitigation costsRadon professionals in Iowa
How do I get a radon test in Iowa?
EPA says you can test your home yourself or hire a qualified radon test company, and that either approach takes only a small amount of time and effort. The Iowa radon program is the place to ask about certified testers and any test kit offer it runs.
How to test a homeFree and low-cost kits by stateIowa radon program
Which Iowa counties are in EPA radon Zone 1?
99 counties are in Zone 1: Adair County, Adams County, Allamakee County, Appanoose County, Audubon County, Benton County, Black Hawk County, Boone County, and 91 more in the county table on this page. Zone 1 is EPA's class for highest predicted potential, a predicted average indoor screening level greater than 4 pCi/L. A zone is a prediction for a county, not a measurement of any home.
Radon in Adair CountyRadon in Adams CountyRadon in Allamakee County
Which Iowa counties have the highest radon?
99 of Iowa's 99 counties have an EPA radon zone published here. Radon411 will not rank counties on data it does not hold, and a zone is a prediction for an area rather than a measurement of any building.
What share of radon tests in Iowa are high?
CDC has published no statewide radon testing statistics for Iowa, so we cannot give a figure. Where CDC does publish one, the percentage describes radon tests reported to CDC, not homes.
Which EPA region is Iowa in?
Iowa is in EPA Region 7: Midwest.
Do I need to test my home in Iowa?
Yes, wherever you live in the state. Testing is the only way to know the radon level in a specific building. EPA recommends fixing a home when the radon level is 4 pCi/L or higher. EPA recommends considering a fix when the level is between 2 and 4 pCi/L.
Why does this page show coverage rather than one radon level for Iowa?
A statewide figure averages counties with very different geology and very different numbers of reported tests, so it hides more than it shows. The county report is the level at which the EPA zone, the geologic potential and the reported testing statistics are actually published, which is why the county table above links to every one of them.
What these figures mean if you own, buy, sell or rent
The zone counts on this page describe counties across Iowa. They are predictions for areas, and none of them measures your building.
- How to test a home
If you own your home
Test the lowest lived-in level; a short-term kit screens in days, a long-term kit reflects the year.
- Buying a house: radon guide
If you are buying
Ask for past results and any system's post-mitigation test, and test during the sale.
- Selling a house: radon guide
If you are selling
Testing before you list puts the timing in your hands; disclosure rules differ by state.
- Radon in rental homes
If you rent, or rent out a home
A tenant can test; a fix is the owner's to make, and duties differ by state.
How long a test has to run, under what conditions, and what EPA says a result means: the testing standard, in full.
Iowa, Products
Testing and mitigation products
Whatever the figures for Iowa show, only a test tells you about one home.
Testing
- Short-term test kitsPassive detectors exposed for a few days under closed-building conditions, then analyzed by a lab.
- Long-term test kitsDetectors exposed for more than 90 days, for a closer picture of the annual average.
- Continuous monitorsPowered devices that log radon on a repeating cycle, often used for transaction tests.
- Digital detectorsConsumer devices that display a running radon reading without a lab.
- Water radon testsKits for radon dissolved in well water, analyzed by a lab.
Mitigation
- Mitigation fansThe inline fan that keeps a soil depressurization system running, sized by the installer.
- System indicatorsU-tube manometers and fan alarms that show whether a mitigation system is still working.
- Sealing materialsCrack, joint and sump sealing used alongside a mitigation system, not instead of one.
Iowa / Next steps
What to do next
Learn
Know what radon is
What radon is, how it gets indoors, and why a county zone is not a reading for your home.
Learn about radonTest
Test the building you live in
Short-term or long-term, where the device goes, and closed-house conditions.
How to testFix
Bring a high level down
How a mitigation system works, and the retest that confirms it.
How mitigation worksFind a pro
Hire a certified professional
Measurement and mitigation professionals by state, with their certifications.
Find a professional
Informational. Follow EPA guidance. EPA says all radon tests should be taken for a minimum of 48 hours, with windows and doors closed from 12 hours before a short-term test.