16 min read
Radon inspection
How a professional radon test works, what it proves and whether it is worth it.
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Testing for radon
How a radon test works, who can run one, and how to read the number it gives you.
Test
What this topic covers
These guides cover how a radon test is run, what a professional inspection involves, how to read the number a test gives, and the reference points EPA and WHO set.
“All homes should be tested for radon.”
EPA “…all radon tests should be taken for a minimum of 48 hours.”
EPA
Guides
Guides and pages in Test
7 to read, the one to start with first.
- Overview page
How to test for radon
Which test to choose, how to place it, closed-house timing, how to read the result, and the mistakes that throw off a reading.
- Overview page
What radon levels mean
A radon test result is a number in pCi/L. What that number means, why it varies, EPA's thresholds, and how to read your own result.
- Overview page
What does radon testing cost?
What drives the price of a radon test, what a written quote should include, and how to compare quotes from different professionals.
Short answers
Questions in Test
The 6 most asked of 27, each with its short answer.
How do I test for radon?
Use a short-term test kit in the lowest lived-in level of your home, or hire a qualified tester: close windows and doors 12 hours before, set the device at least 20 inches off the floor away from drafts, leave it at least 48 hours, then mail it to the lab.
Read the full answerHow do you know if you have radon in the house?
Only by testing.
Read the full answerIs a radon level of 4.1 considered high?
Yes, by EPA's measure: 4.1 pCi/L is just above EPA's 4 pCi/L action level, the point at which EPA recommends fixing a home.
Read the full answerWhat is a safe level of radon?
No level of radon is known to be safe: any exposure carries some risk, and lowering the level lowers the risk.
Read the full answerShould I test for radon?
What is radon testing?
Radon testing is measuring the radon concentration in a building's air over a set period, with a detector that is either analyzed by a laboratory afterward or reports the result itself.
Read the full answer