Can I test for radon myself?

Whatever the source, use a device from a qualified laboratory and follow that laboratory's instructions. Kit options side by side are on the radon test kits page.

1. 1

   Close up the house

   Shut windows and outside doors at least 12 hours before a short-term test of 2 to 4 days, and keep them shut except for normal coming and going. Turn off fans that bring in outside air.

2. 2

   Pick the spot

   The lowest lived-in level: the basement if it is used often, otherwise the first floor. In an apartment, the lowest level within your unit. Avoid kitchens, bathrooms, laundry and furnace rooms.

3. 3

   Place the kit

   At least 20 inches above the floor, where it will not be disturbed, away from drafts, high heat, high humidity and exterior walls.

4. 4

   Leave it alone

   For the time the instructions say, and never less than 48 hours. Run heating and cooling normally; for tests under a week, use only air conditioners that recirculate indoor air.

5. 5

   Send it back

   Fill in the start and stop times and the location, and mail the device to the laboratory promptly. The kit says where to send it.

Short tests of under four days are not run during unusually severe storms or high winds. More on test conditions is in can you be in the house during a radon test.

Do-it-yourself kits come in both lengths. Short-term kits stay in the home from two to 90 days, depending on the device, for quick results. Long-term kits stay more than 90 days and tell you your home's year-round average. Because radon varies from day to day and season to season, the longer the test, the better it reflects your home.

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Test	How long it runs	What it is for
Short-term test	Stays in the home from 2 to 90 days, depending on the device, and for a minimum of 48 hours.	A faster screening result. Because radon levels vary from day to day and season to season, it is less likely than a long-term test to tell you the year-round average.
Long-term test	Stays in the home for more than 90 days.	It is more likely than a short-term test to tell you the home's year-round average radon level.
Continuous monitor	Logs readings for the whole test, run as a short-term or a long-term test under the same durations in EPA guidance.	Logs a graph over time, so you can see trends and spot anomalies rather than a single number.

A short-term kit is the usual first test. If it comes back high, a second kit, either long-term or another short-term test, is the follow-up before deciding on a fix.

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1. 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.

2. 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.

3. 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.

The laboratory reports a number in picocuries per liter (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. If you followed up a short-term test with a second short-term test, use the average of the two. See how to read a radon test for the details.

There are two kinds of radon testing: for people testing their own home, and for real estate sales. A kit suits the first. In a sale, hiring a qualified tester is recommended, because there is a risk of interference and buyers often want a result from someone not involved in the sale.

A tester can also provide an independent result, which matters when a sale depends on it. Find one in the measurement professionals directory, or read should I get a radon test with my home inspection.