Radon
Radon Testing
Radon is colorless, odorless, and tasteless, so the only way to know if a structure has elevated levels is to test. There are many kinds of low-cost "do it yourself" radon test kits available through the mail, at hardware stores, building supply stores, or other retail outlets. Test kits should display "Meets EPA Requirements" to insure reliability. County health departments, local American Lung Associations, or county cooperative extension offices may be able to advise on sources.
Trained contractors can be hired to test for radon if preferred or for real estate transactions. Use of certified contractors is recommended. Radon measurement providers may be certified by the National Environmental Health Association (NEHA) or the National Radon Safety Board (NRSB).
Testing is the only way to know if a home has an elevated level of radon. Testing is inexpensive and easy. The Environmental Protection Agency and the Surgeon General both recommend testing all homes below the third floor. They further recommend that if radon levels of 4 picocuries per liter or more are found that the home be fixed. The amount of radon in the air is measured in "picocuries per liter of air (pCi/L). Test results are also sometimes expressed in Working Levels (WL).
Short-term Testing is the quickest way to determine if a potential radon problem exists. Short-term tests remain in the home for two to 90 days, depending on the device. "charcoal canisters," "alpha track," "electret ion chamber," "continuous monitors," and "charcoal liquid scintillation" detectors are most commonly used for short-term testing. Because radon levels tend to vary from day to day and season to season, a short-term test is less likely than a long-term test to tell a year-round average radon level.
Long-term Testing is the most accurate way to test for radon. Long-term tests remain in the home for 91 days to a full year. "Alpha track" and "electret" detectors are commonly used for long-term testing.
EPA Recommends the Following Testing Steps:
Step 1: Take a short-term test. If your result is 4 pCi/L or higher*, take a follow-up test to be sure (Step 2).
Step 2: Follow up with either a long-term test or a second short-term test:
- For a better understanding of the year-round average
radon level, take long-term test. - If you need results quickly, take a second short-term test.
The higher the initial short-term test result, the more certain that a short-term rather than a long-term follow up test should be taken. If the short-term test result is several times the action level, for example 10 pCi/L or higher, a second short-term test should be taken immediately.
Step 3: If a long-term follow up test was taken: Fix the home if the long-term test is 4 pCi/L or more. If a second short-term test was taken: The higher the short-term results, the more certain that the home should be fixed. If the average of the first and second test is greater than 4 pCi/L or higher* fixing the home should be considered.
*0.02 Working Levels (WL) or higher.