Testing for Radon
How do I test my house?
Testing for radon is simple and inexpensive.
There are many "do-it-yourself" kits you can buy at retail outlets or through the mail. (See next question for where to get a test kit.) You should only purchase EPA certified radon tests kits. These kits and their providers have met EPA's qualifications for radon measurement.
For 12 hours prior to taking the test, and as much as possible during the test, keep all doors and windows closed. You do not have to vacate your home while testing. EPA recommends placing the radon kit in the lowest lived-in level of the home (for instance the basement if it is frequently used, otherwise the first floor). You should test a room that is used regularly, but not the kitchen or bathroom. For placement, follow the instructions that come with the test kit.
Once the test is complete, reseal the kit and send it to the lab specified on the package.
The quickest way to test is with a short-term test. These devices (charcoal canisters, alpha track, electret ion chamber, continuous monitors or charcoal liquid scintillation) remain in the home for two to 90 days. To make sure of the reading follow-up with another short-term kit and average out the two readings.
A long-term device which stays in the home for 90 days to one year (such as a alpha track or electret detectors) will give you a reading that is more likely to tell you the home's year-round average radon level. That's important because of seasonal and other variations.
You may also hire a company to test your home for you. Make sure the company is listed in EPA's Radon Measurement Proficiency Program or certified by your state. Your state radon contact and the Radon Helpline, (800) 557-2366, can provide a list. Ask to see the professional radon tester's EPA photo I.D. card.
You can also browse the Radon Proficiency Program listing on-line to find a certified contractor in your state.
Where can I buy a test kit?
Test kits are generally available from hardware stores, supermarkets, and other retail outlets, and also through the mail for prices ranging from $10 to $45.
Look for a test kit that is certified by your state or is listed by EPA's Radon Measurement Proficiency Program. It will say "Meets EPA Requirements" on the package.
The Air Quality Program offers low-cost short- and long-term radon test kits to anyone who wants to test their home. For more information about our test kit offer...
My neighbor has tested and found an elevated radon level (or found a very low radon level) does this mean I should (or shouldn't) be concerned?
No. Having a neighbor that has tested high (or low) for radon is no guarantee that your house will test similarly. The only way to know if a house has a high level of radon is to test.
What do these results mean?
Radon is measured in picocuries per liter of air (pCi/L). The average indoor level is 1.3pCi/L and about 0.4 pCi/L is normally found in the outside air. EPA recommends that action be taken to reduce the indoor radon levels that are above 4 pCi/L. Most homes today can be reduced to 2 pCi/L or below. There is really no "safe" level. Any level of radon exposure carries some risk.
Are radon testing kits accurate?
Responsible test kits, when used as directed, provide reliable indications of radon concentrations over the time the kits are used. Test kits that have successfully passed the EPA Radon Measurement Proficiency Program are marked "Meets EPA Requirements." Long-term test kits (90 days to 1 year) will give a better indication of annual average radon levels.
When should short-term tests be conducted?
Does time of year matter?
Winter readings are typically higher than those taken in summer. During winter, the larger differential between outdoor and indoor pressure is likely to lead to higher entry of radon into a house than would occur in summer. In addition, your home is likely to be less ventilated in the winter. EPA recommends testing in the winter.
Why should I spend more for a long-term test than for a short-term test that gives me quicker results?
The long-term radon test kits take into consideration seasonal variation, which can be substantial and therefore provide a better measure of annual average radon exposures than short-term tests. The less expensive short-term kits provide a good indicator of whether additional testing is warranted. If a short-term test result is greater than 4 pCi/L, EPA recommends following up with a long-term test, or a second short-term test, to confirm the result.