Skip to content
RADON411
$5

County radon report

Get it

Independent U.S. radon data

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

Radon411 is an independent U.S. radon data site: the EPA radon zone and reported radon tests for every county, plain guides to radon testing and radon mitigation, and certified radon professionals with their published certifications. A dated PDF report for one place costs $5.

See the radon levels for your county or ZIP code

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

Every radon fix starts here: your county's radon report

Radon is responsible for about 21,000 lung cancer deaths every year, EPA estimates. Testing is the only way to know if you and your family are at risk from radon. For $5, start with your county's radon picture and exactly what to do this week.

  1. Your county's numbers, in one placeEPA's zone and the tests reported to CDC, labelled and dated, instead of digging through several agency sites.
  2. Your plan for this weekWhich test, where to put it, how long it runs, and what EPA says to do with the result.
  3. What a fix costs, and who can do itPublished cost figures, your state's disclosure rule, and listed professionals near you, written for your role.
$5

$5 report + $0.46 card processing

Less than a short-term test kit, and it tells you which test you need and what to do with the number.

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

1,327 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