Locations and reports
Radon Levels in Guam
What this means for you
- Your area: EPA has not published a radon zone for Guam.
- Local tests: CDC has published no radon test results for Guam.
- 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.
Predicted: EPA radon zone
No EPA zone on file
EPA has not published a radon zone for Guam.
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 has published no radon test figures for Guam or its counties. Only a test tells you the level in a home.
Guam, In figures
Guam in figures
What the published data says about Guam, in words. A zone and a share of tests describe an area, never the level in any one home.
Predicted
PredictedNo EPA zone is on file for Guam, which is one county-level area.
Reported tests
MeasuredCDC has no statewide testing figure for Guam on file here.
No Guam county has a published CDC county figure on file here.
Guam, Counties
Guam counties by EPA zone
PredictedGuam is one county-level area, and it has its own county report.
No EPA zone on file1
Guam, Local resources
Local resources in Guam
Who to ask in Guam: the state's radon program, test kits and professionals.
Guam's radon program
Every state has a radon office that answers questions about testing and local rules. Find Guam’s on the state radon programs list.
Test kits
Ask the program whether it has free or discounted kits, or compare kits you can buy.
Radon professionals
No professionals are listed in Guam yet. The state program can point you to registered testers and mitigators.
See the Guam directoryGuam, Questions
Questions about radon in Guam
Common questions8 questions, answered from the figures above
Is radon a problem in Guam?
EPA's Map of Radon Zones places 0 of the 1 Guam 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.
How do I get a radon test in Guam?
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. Your state radon program is the place to ask about certified testers and any test kit offer.
How to test a homeFree and low-cost kits by stateGuam radon program
Who does radon mitigation in Guam?
Radon411 has no certified mitigators listed for Guam yet. 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 Guam
Which Guam counties have the highest radon?
EPA has not published a radon zone for Guam. 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 Guam are high?
CDC has published no statewide radon testing statistics for Guam, 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 Guam in?
Guam is in EPA Region 9: Pacific Southwest.
Do I need to test my home in Guam?
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 Guam?
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
This page holds no radon measurement for Guam yet, so there is nothing here that could stand in for testing 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.
Guam, Products
Testing and mitigation products
Whatever the figures for Guam 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.
Guam / 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.