Radon Testing Tips
When to test for radon
Radon levels fluctuate
Radon levels fluctuate widely and depend on many factors like barometric pressure, wind speed, heating season. The short-term test is a snapshot over 3 or 4 days. The long-tem alpha track detector averages the fluctuations over 3 to 12 months.
EPA recommends two short-term radon test kits side by side, or a second test immediately after the first one using an identical radon test device in the same location.
Radon testing location
EPA recommends that you test in the lowest level of the home which is suitable for occupancy. But the buyer decides based on their expected use of the home. If they plans to finish the basement, it becomes the proper location for the test.
Some states and real estate practices require testing in the "lowest livable area" whether or not currently suitable for occupancy. This usually means radon testing in the basement.
Conducting the test
Closed-building conditions are required for test measurements lasting less than 90 days in order to stabilize th concentrations of radon and radon decay products and increase reproducibility of the measurement. Other than a furnace or permanently installed heat recovery ventilators, external-internal air exchange systems should not operate.
Repeating the radon test
Select a procedure that best suits your goals. If you detect significant radon and want to know exactly your radon level, repeat the test.
If you plan to sell the house and your short-term radon test comes out anywhere close to 4 pCi/L, reduce the radon level and re-test afterwards. Otherwise, your closing is likely to evaporate by a radon reading of 4.1 pCi/L. What should be your safety margin? Because radon level fluctuate widely, it depends on your judgment.
If you plan to live in the house, you are motivated to provide a safe home for your family. If your radon level is significant (above the US average of 1.25 pCi/L), work on reducing the radon level. For tips on sealing any openings and the concrete, check out RadonSeal radon mitigation. Re-test after the repairs