Locations and reports
Radon in Washington, District of Columbia
Washington, District of Columbia lies in District of Columbia, which EPA places in Zone 3, lower predicted potential. Radon data is published by county, so this page reads District of Columbia's figures.
What this means for you
- Your area: EPA rates District of Columbia, where Washington is, Zone 3, the lowest of its three radon zones. That is a prediction for the whole county, and homes with elevated levels occur in all three zones.
- Local tests: Of 2,126 radon tests reported to CDC for District of Columbia (2008 to 2017, laboratory), 8.7% were at or above 4 pCi/L, EPA's action level.
- 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.
Washington, What is published
What is published for Washington
Radon data is published by county, not by city
Radon data is published by county, not by city. EPA assigns radon zones to counties, and CDC publishes radon test figures by county. Neither publishes a figure for Washington, so every radon figure on this page belongs to a county and is labelled with it. Only a test tells you about one home.
District of Columbia has an EPA zone and its own CDC test figures, shown below. About 693,645 people live in Washington.
Washington, Counties
The county Washington lies in
MeasuredEach county's own EPA zone and its own published CDC figures for 2008 to 2017, laboratory, the newest period any of them has. A county without a figure for that period is shown without one, never with a figure from another year.
District of ColumbiaZone 3Lower predicted potential
- 8.7%
- Reported tests at or above 4 pCi/L, 2008 to 2017, laboratory
- 1.2 pCi/L
- Median reported result
- 2,126 tests
- Tests reported to CDC
- 0
- Annual years on file
The median reported pre-mitigation result for 2008 to 2017, laboratory was 1.2 pCi/L in District of Columbia.
CDC counts radon tests that were reported to it, not homes, and figures from few tests can swing widely from year to year. Each county’s report has its full history.
Predicted: EPA Map of Radon Zones, by county. Measured: CDC tracking data, by county, 2008 to 2017, laboratory.
Washington, Local resources
Local resources for Washington
Who to ask in District of Columbia: the state's radon program, test kits and professionals.
Radon Test Kit Program
District of Columbia’s radon program answers questions about testing, mitigation and the rules where you live.
- Phone
- (202) 535-2302
Test kits
The program says: District residents can obtain a free radon test kit to reduce prolonged exposure to harmful levels of radon in the home.
Radon professionals
Radon testers and mitigators in District of Columbia, each with how its listing was checked.
Professionals in District of ColumbiaWashington, Questions
Questions about radon in Washington
What radon zone is Washington in?
EPA's Map of Radon Zones classifies counties, not cities. District of Columbia is in Zone 3 (lower predicted potential). A zone is a prediction for a whole county and never tells you the level in one home.
How many radon tests come back high in Washington's counties?
For 2008 to 2017, laboratory, the share of radon tests reported to CDC that were at or above 4 pCi/L was 8.7% in District of Columbia (2,126 tests). Each is that county's own figure, counting tests reported to CDC, not homes. Radon411 does not average or combine them into a figure for the city.
Should I test my home in Washington?
Yes. 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. How to test a home.
The answers use the published figures of District of Columbia, the county Washington lies in.
Washington / 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