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RADON411
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County radon report

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Independent U.S. radon data

Radon levels by county, and how to test and fix your home

Radon411 is an independent U.S. radon data site. Look up any state or county for its EPA radon zone and the radon tests reported there, read plain guides to radon testing and radon mitigation, and find certified radon professionals with their published certifications. For $5, get a dated PDF report for one place.

See the radon levels for your county

Start here

Start with your situation

Choose the one closest to yours. Each opens the guide written for it.

Your area

Radon zones and tests for all 3,231 U.S. counties

EPA puts every county in one of three zones by its predicted average indoor radon level. A zone is a prediction for the whole county, not a reading of any home. Every state and county has a free page: choose yours on the map, type it, or find it in the list.

Map of the United States with every county shaded by its EPA radon zone: Zone 1 red, Zone 2 amber, Zone 3 pale.AlabamaAlaskaArizonaArkansasCaliforniaColoradoConnecticutDelawareDistrict of ColumbiaFloridaGeorgiaHawaiiIdahoIllinoisIndianaIowaKansasKentuckyLouisianaMaineMarylandMassachusettsMichiganMinnesotaMississippiMissouriMontanaNebraskaNevadaNew HampshireNew JerseyNew MexicoNew YorkNorth CarolinaNorth DakotaOhioOklahomaOregonPennsylvaniaPuerto RicoRhode IslandSouth CarolinaSouth DakotaTennesseeTexasU.S. Virgin IslandsUtahVermontVirginiaWashingtonWest VirginiaWisconsinWyoming
Predicted: EPA Map of Radon Zones, every U.S. county. Choose a state to open its page.
  • Zone 1Highest predicted potential, predicted greater than 4 pCi/L1,071counties
  • Zone 2Moderate predicted potential, predicted 2 to 4 pCi/L1,034counties
  • Zone 3Lower predicted potential, predicted less than 2 pCi/L1,033counties
  • No zone on fileEPA has published no zone for these93counties

Measured: tests of other buildings are on file for 2,862 counties, never a reading of your home.

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.

Open the radon map

Every state and territory

Northeast9
Midwest12
South17
West13
Territories5

RADON411 Location Report

Get the radon report for your county, as a PDF you can forward

Every page here stays free. For $5 you get a dated PDF report for one place, written for your role.

  1. Only radon, and completeEPA's zone, the tests on file, how to test, what a fix costs, and listed professionals.
  2. Written for your roleA cover letter, your state's disclosure rule and the questions to ask.
  3. Built to forwardEvery figure dated and sourced. Area data, never a reading of a home.
$5

$5 report + $0.46 card processing

Less than a coffee. Reads like a consultant memo.

Area data. Not a measurement of a building.

Example layout. Your report opens on your own place, with its own figures.

Four steps

Learn, test, fix, find a pro

The whole path, from a county report to a confirmed fix in your own home.

  1. 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 radon

  2. Test

    Test the building you live in

    Short-term or long-term, where the device goes, and closed-house conditions.
    How to test

  3. Fix

    Bring a high level down

    How a mitigation system works, and the retest that confirms it.
    How mitigation works

  4. Find a pro

    Hire a certified professional

    Measurement and mitigation professionals by state, with their certifications.
    Find a professional

Guides

A guide for every topic

Plain answers on what radon is, how to test a home and how to bring a high level down.

See all guides, by topic

Get help

People and tools for the job

Radon411 does not certify anyone or perform tests. It lists what is published, so you can compare and choose.

Professionals

Certified radon professionals

1,322 measurement and mitigation businesses are listed, each with its certification shown the way the certifying body published it.

Find a professional

Test kits

Test kits and monitors

11 products are compared on their published specifications. Affiliate links are labeled where they appear.

Compare test kits

Your next step

Look up the place you care about

Every state and county has a free report: its predicted zone, the tests on file and what to do next.

Find your county