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How to Test A Home for Radon

Radon is a health hazard with a simple solution.
Testing is the first step. Luckily, radon testing is easy and low cost. There are many kinds of do it yourself radon test kits.

Short-term tests (2-90 days) and long-term tests (91 days - 1year) are most commonly used to test for radon. Both types of test kits are usually found at your local hardware store or can be ordered online through organizations like The American Lung Association of Oregon. For more details, please visit Types of Radon Gas Testing.

If you are buying or selling a home, or if you simply prefer, you can hire a local qualified radon testing professional to do the testing for you. You can find a list of Oregon measurement companies here.

How is radon measured?

Radon is measured by picocuries per liter of air (pCi/L). The Environmental Protection Agency (EPA) recommends taking corrective action if radon levels are 4.0 pCi/L or above.
Since radon is a naturally occuring substance, you can never completely get rid of it. The average outdoor radon concentration is 0.4 pCi/L, whereas the average indoor radon concentration is 1.3 pCi/L. It is important to note that there is no safe level of radon; however, it is long-term exposure to elevated levels of radon that pose the most risk. You can reduce the risk by lowering the radon level in your home.

What your test results mean:

EPA recommends you begin with a short term test for more immediate results. If your result is 4 pCi/L or higher, take a follow up test to be sure.

Depending on the results of your first test, follow up with either a long-term test or a second short term test. If your first test results are 4 to 8 pCi/L follow up with a long-term test. If your first test results are 8 pCi/L or above, follow up with another short-term test. If the average of your two short-term tests is 4 pCi/L or above, or the result of your long-term test was 4 pCi/L or above, fix your home. To learn more about how to fix your home, visit About Radon Mitigation.

If your test results are below the action level of 4.0 pCi/L, you may want to re-test in two to five years. You should test again if anything is done to the house that may change the air pressure like home renovation or the installation of new heating or air conditioning systems.

Testing reminders to ensure accurate results:

  • Follow the directions on your kit!
  • Testing should be done in the lowest livable area of your home (the basement if it is frequently used, otherwise the first floor).
  • Keep windows and outside doors shut except for normal entry & exit from the home.
  • Test placement should be away from drafts, high heat, high humidity and exterior walls of the home (kitchen, bathrooms, or laundry rooms).
  • Once the test is finished, send the test kit immediately to the laboratory specified on the package. Most test kits are manufactured to be accurate as long as they make it back to the lab within eight days after testing has stopped. A test processed after that point may give invalid results.
  • Don't forget to note down the test serial number!

IMPORTANT: Most short-term kits come with the postage pre-paid. If you know regular US Mail is slow in your area, we recommend you send it to the lab using 2-3 day US Priority Mail (or an overnight service like FedEx).