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Buying and selling5 min read

Should I get a radon test with my home inspection?

By Radon411 Editorial TeamUpdated How we research

Short answer

Yes, unless the house has a recent test you can rely on: if the home has not been tested, have it tested, and a qualified radon tester is very often a home inspector. Ask for the test by name, and schedule it early, since every radon test runs at least 48 hours.

Next step: see how a radon test fits a home sale. Testing for a home sale

Know the indoor radon level of any home you consider buying. In a sale, the test goes in the lowest level that could be used regularly, finished or not, since a buyer may live lower in the home than the seller did, and any of three short-term options is acceptable when results are needed quickly.

Buyers frequently want tests made by someone not involved in the home sale. Ask the tester about certification, through the National Radon Proficiency Program () or the National Radon Safety Board (), and how they prevent or detect test interference.

If the seller offers an earlier result, check its results, who ran it and where it was placed, and whether the house has changed since. If the house has a radon system, ask for its information and test with it running.

What to do next: add a radon test to your inspection request, and settle in the contract when any would be done and who would pay.

Why add radon to the inspection

If you are buying a home, have it tested for radon, and know the indoor radon level of any home you consider buying. If the home has not yet been tested, have it tested. The inspection period is the natural time: a qualified radon tester is very often a home inspector.

When a radon test belongs in your inspection
SituationWhat to do
No radon test on recordAdd a radon test to the inspection
The seller has a testCheck it; ask for a new one if it does not hold up
The last test is not recent, for example within two yearsExpect to test again
The home was renovated or altered since the testTest again
The home has a radon systemAsk for its records and test with it running

Real estate sales happen quickly, and there is often little time to deal with radon, so ask for the test by name when you book the inspection.

How the test fits the inspection timeline

All radon tests should run for a minimum of 48 hours. For a of 2 to 4 days, start at least 12 hours before the test and last through it. When results are needed quickly in a sale, any of three short-term options is acceptable for deciding whether the home should be fixed.

EPA's three short-term radon testing options for a real estate transaction: two tests at the same time, one test then a second, or a continuous monitor, each for at least 48 hours, with what to do after each.
Read this figure as text

If you are testing in a real estate transaction and you need results quickly, any of the following three options for short-term tests are acceptable in determining whether the home should be fixed.

  1. Option 1. Two tests at the same time

    Passive

    Take two short-term tests at the same time in the same location for at least 48 hours.

    What to do nextFix the home if the average of the two tests is 4 pCi/L or more.

    Two tests taken at the same time (simultaneous) would improve the precision of this radon test.

  2. Option 2. One test, then a second

    Passive

    Take an initial short-term test for at least 48 hours. Immediately upon completing the first test, do a second test using an identical device in the same location as the first test.

    What to do nextFix the home if the average of the two tests is 4 pCi/L or more.

    One test followed by another test (sequential) would most likely give a better representation of the seasonal average.

  3. Option 3. A continuous monitor

    Active

    Test the home with a continuous monitor for at least 48 hours.

    What to do nextFix the home if the average radon level is 4 pCi/L or more.

    Both active and passive devices may have features which help to prevent test interference.

Any real estate test for radon should include steps to prevent or detect interference with the test device. Your state radon office can help you decide which option is best.

The three short-term options for a home sale: two tests at once, one after another, or a continuous monitor.

If the test uses a device sent to a lab, allow for the turnaround; results usually come within a few weeks.

Where the test goes in a house you are buying

In a sale, the test goes in the lowest level of the home that could be used regularly, finished or not, because a buyer may choose to live in a lower area than the seller did. That means any space you might use as a bedroom, play area, family room, den, exercise room or workshop.

Choosing who runs the test

Buyers frequently want tests made by someone who is not involved in the home sale, and a test by an independent, qualified radon tester is recommended. There is a potential for test interference in real estate transactions, so any sale test should include steps to prevent or detect it.

Questions to ask a radon tester
AskWhy
Are you certified?National credentials come from the National Radon Proficiency Program (NRPP) and the National Radon Safety Board (NRSB)
Do you also install radon systems?A potential conflict of interest exists if the same firm tests and mitigates
How do you prevent or detect interference?Any real estate test should include such steps
Which of the three short-term options will you use?Each takes at least 48 hours

In states that do not regulate radon services, ask whether the tester holds a professional proficiency or certification credential. See find a measurement professional.

Using the seller's result instead

You may accept an earlier result from the seller or ask for a new test by a qualified tester. Before you accept it, check the results, who conducted the test, and where in the home it was taken, especially if you plan to live on a lower level. Make sure the test followed the Radon Testing Checklist, and if you want a new test, raise it with the seller as soon as possible.

Contract terms for a radon test
TermSettle in advance
LocationWhere the test will be located
TesterWho should conduct the test
Method and timingWhat type of test, and when
CostsHow buyer and seller share the results and test costs
The fixWhen mitigation will be done, and who pays

Questions about radon and home inspections

Is radon testing part of a standard home inspection?

Ask for it by name. A qualified radon tester is very often a home inspector, but the radon test should be on your inspection request.

How long does a radon test take during an inspection?

A minimum of 48 hours, with closed-house conditions from at least 12 hours before a short test of 2 to 4 days.

Should the seller or the buyer pay for the radon test?

It is negotiable. The contract can say how the buyer and seller share the test results and costs.

Can I use the seller's radon test?

You may, after checking its results, who ran it, where it was placed and that it followed the testing checklist.

What if the radon test comes back high?

Agree with the seller on when mitigation will be done and who will pay for it. See should I buy a house with radon.

Can the inspector who tests also fix the radon?

A potential conflict of interest exists if the same person or firm tests and installs the system. Keep the test independent.

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