16 min read
Radon inspection
How a professional radon test works, what it proves and whether it is worth it.
Read the guideShort answer
January is National Radon Action Month, and the first thing on EPA's list for the month is to test your home. Five steps cover it: pull the brief for your county, test this week, read the result against 4 pCi/L, write who pays for a fix into the contract, and retest after a fix.
Next step: pick the right test for your home. Which test to use
Key takeaways
- EPA says January is National Radon Action Month, and its list of things to do during the month starts with testing your home.
- EPA and the U.S. Surgeon General recommend that all homes in the U.S. be tested for radon.
- The brief is area data for your county, not a test of the building. Only a test measures the building.
- EPA's Home Buyer's and Seller's Guide says all radon tests should be taken for a minimum of 48 hours.
- In a sale, EPA says to agree when radon mitigation measures will be taken, and who will pay for them.
Step by step · 1 min read
The five steps at a glance
Step 1 of 5:
Pull the brief
The county record in one dated file: EPA's predicted zone, the tests on file for the area, your state's rule and the questions to settle.
Step 2 of 5:
Test this week
A short-term test on the lowest lived-in level, for at least 48 hours, with windows and outside doors closed.
Step 3 of 5:
Read the result against 4 pCi/L
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.
Step 4 of 5:
Write who pays into the contract
In a sale, the contract can say when a fix happens and who pays for it. In a rental, the rules depend on the state.
Step 5 of 5:
Retest after a fix
EPA says to test your home again after it is fixed, and to retest at least every two years.
Overview · 1 min read
Step 1: Pull the brief
The Radon Action Brief is the county page you hand the inspector before the monitor goes down: the published radon data for the place, your state's rule and the questions to settle, in one dated file. It describes the area. It is not a reading of the building, and it does not replace a test.
Read moreA paragraph, 1 min
Why a county record still needs a test: EPA's publications page says of its Map of Radon Zones that homes with elevated levels of radon have been found in all three zones, and that all homes should be tested regardless of geographic location. The brief tells you what is known about the area before the test; the test tells you about the building.
What the brief holds
A list and a paragraph, 1 min
- Cover: the place, your role, the report ID and date
- The area data: Predicted, Measured and Calculated, each labeled, beside the neighbors and the state
- Every source, with its date
- A cover letter for your role
- Your state's disclosure rule
- Questions to ask
- How to read a measurement report
- How to test this week
- One-page cost sheet
- Nearby listed professionals
- A printable test log
The parts after the first three are chosen in the builder, and choosing more or fewer never changes the price. Open the builder below; if you came here from a county page, that county is already filled in.
Pull the brief for your county
Type a ZIP, city or county in the builder. Area data, not a test of the building.
In a picture · 1 min read
Step 2: Test this week
EPA and the U.S. Surgeon General recommend that all homes in the U.S. be tested for radon, and EPA's page for the month says testing is easy and inexpensive. The Citizen's Guide says testing is the only way to know if you and your family are at risk from radon.
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Radon testing checklist
For reliable test results, follow this Radon Testing Checklist carefully.
Before the test
- Notify the occupants of the importance of proper testing conditions.
- Conduct the radon test for a minimum of 48 hours; some test devices have a minimum exposure time greater than 48 hours.
- When doing a short-term test ranging from 2-4 days, it is important to maintain closed-house conditions for at least 12 hours before the beginning of the test and during the entire test period.
- If you conduct the test yourself, use a qualified radon measurement device and follow the laboratory's instructions.
- If you hire someone to do the test, hire only a qualified individual.
- If the house has an active radon-reduction system, make sure the vent fan is operating properly.
During the test
- Maintain closed-house conditions during the entire duration of a short-term test, especially for tests shorter than one week in length.
- Operate the home's heating and cooling systems normally during the test.
- Do not disturb the test device at any time during the test.
After the test
- If you conduct the test yourself, be sure to promptly return the test device to the laboratory.
- Be sure to complete the required information, including start and stop times, test location, etc.
- EPA recommends that you fix the home when the radon level is 4 pCi/L or more.
Closed-house conditions means keeping all windows closed, keeping doors closed except for normal entry and exit, and not operating fans or other machines which bring in air from outside.
Show the whole figure
Read moreTwo paragraphs, 1 min
Pennsylvania's Department of Environmental Protection says the best time to test is during the colder months, when homes and buildings are closed and radon is most likely to be trapped and build up to higher levels. EPA's test kit page says free test kits are sometimes available from local or county health departments, or from state radon programs. See free and low-cost kits by state.
In a picture · 1 min read
Step 3: Read the result against 4 pCi/L
EPA recommends fixing a home when the radon level is 4
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1Step 1: Take a short-term test.
- Below 4 pCi/LEven if your test result is below 4 pCi/L, you may want to test again sometime in the future.
- At or above 4 pCi/LIf your result is at or above 4 pCi/L, take a followup test to be sure.
2Step 2: Follow up with either a long-term test or a second short-term test.
- Long-term testFor a better understanding of your year-round average radon level, take a long-term test.
- Second short-term testIf you need results quickly, take a second short-term test. If your first short-term test result is more than twice EPA's 4 pCi/L action level, you should take a second short-term test immediately.
3Step 3: Decide whether to fix your home.
- After a long-term testFix your home if your long-term test result is 4 pCi/L or more.
- After a second short-term testConsider fixing your home if the average of your first and second test is at or above 4 pCi/L.
Show the whole figure
Read moreA paragraph, 1 min
The Citizen's Guide says radon levels tend to vary from day to day and season to season, so a short-term test is less likely than a
At a glance · 1 min read
Step 4: Write who pays into the contract
In a home sale, EPA's Home Buyer's and Seller's Guide says that if elevated levels are found during the real estate transaction, the buyer and seller should discuss the timing and costs of radon reduction. It lists what the two sides can settle in the contract, from where the test will be located to when radon
| Item | In EPA's words |
|---|---|
| Where | Where the test will be located |
| Who tests | Who should conduct the test |
| Which test | What type of test to do |
| When | When to do the test |
| Results and test costs | How the seller and the buyer will share the test results and test costs |
| The fix | When radon mitigation measures will be taken, and who will pay for them |
Show all 6 rows
Read moreA paragraph and a note, 1 min
In a rental, who pays depends on the state. Idaho's program says landlords aren't required to test for or fix radon issues, but you can test the space yourself and discuss the results with them. Maine's landlord disclosure form says radon mitigation is recommended, but not required. See radon in rental homes for each state's rule.
In a picture · 1 min read
Step 5: Retest after a fix
The Citizen's Guide says radon reduction systems work, and that you should also test your home again after it is fixed. EPA's Consumer's Guide to Radon Reduction says a
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Day of installation
The system goes in
Keep the fan running at all times: it must run continuously for the system to work correctly.
No sooner than 24 hours
Earliest post-mitigation test
Test no sooner than 24 hours after your system is in operation with the fan on, if it has one.
Within 30 days
Post-mitigation test done
A two- to seven-day measurement is recommended, and EPA recommends an independent follow-up radon measurement as well as any test the contractor runs.
At least every two years
Retest
Retest your home at least every two years to be sure radon levels remain low.
Test conditions: Windows and doors must be closed 12 hours before and during the test, except for normal entry and exit. Not drawn to scale.
After a remodel. After you remodel, retest in the lowest lived-in area to make sure the construction did not reduce the effectiveness of the radon reduction system.
Show the whole figure
Read moreA paragraph, 1 min
Washington's Department of Health puts it plainly: whether you, your landlord, or someone you hired makes the fixes necessary to reduce radon in your home, make sure you retest when the work is done. In a sale, EPA's Home Buyer's and Seller's Guide says to test again after the radon mitigation work has been completed to confirm that previous elevated levels have been reduced.
Questions · 1 min read
Questions about the checklist
Is the brief a radon test?
No. It is area data for the county, not a test of the building. EPA says homes with elevated levels of radon have been found in all three zones, so only a test tells you about your building.
How long should a January radon test run?
EPA's Home Buyer's and Seller's Guide says all radon tests should be taken for a minimum of 48 hours. Short-term tests remain in your home for two days to 90 days, depending on the device.
What if my result is 4 pCi/L or more?
Take a follow-up test to be sure, the Citizen's Guide says. EPA recommends fixing a home when the radon level is 4 pCi/L or higher.
Who pays for a radon fix in a home sale?
Whoever the contract says. EPA's Home Buyer's and Seller's Guide says the buyer and seller should discuss the timing and costs of radon reduction, and agree when radon mitigation measures will be taken, and who will pay for them.
When do I retest after a fix?
EPA's Consumer's Guide says within 30 days of system installation, but no sooner than 24 hours after the system is in operation, and then at least every two years.
Is January a good month to test?
Pennsylvania's DEP says the best time to test is during the colder months, when homes and buildings are closed. EPA's Citizen's Guide does not name a best month; it says levels vary from day to day and season to season.
Radon Action Brief
National Radon Action MonthPre-sale
The county page you hand the inspector before the monitor goes down.
- Your area's radon record, explained. EPA's zone and any CDC tests.
- Your plan to test this week. Which test, where it goes, how long.
- Fix costs and pros near you. Costs, EPA's checklist, listed pros.
Save 64%Sale price: $8.99Price after the sale: $25Ends Jan 31Then $25Sale ends January 31, then $25
Test
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