The first step is to perform a short-term measurement* in the lowest structural areas**.

Perform Short-Term Test If the result is less than 4pCi/L If the result is 4pCi/L or more, but less than 8 pCi/L If the result is 8 pCi/L or more No further action is required. Retest in 2 years or if any renovations or additions are made to the building. Perform an additional short-term test. For a better understanding of your year-round average perform a long-term test. Perform an additional short-term test. For a better understanding of your year-round average perform a long-term test. If the average of the 2 tests is less than 4 pCi/L If the average of the 2 tests is 4 pCi/L or more If the result is less than 4 pCi/L If the result is 4 pCi/L or more If the 2^nd result is less than 4 pCi/L If the 2^nd result is 4 pCi/L or more No further action is required. Retest in 2 years or if any renovations or additions are made to the building. Fix the home. No further action is required. Retest in 2 years or if any renovations or additions are made to the building. Fix the home. Perform a long-term test. Fix the home.

* Short-term tests may last between 2 and 90 days, most last between 2 and 7 days. Examples of short-term detectors used in home environment testing include: activated charcoal canisters, liquid scintillation vials, electret chambers and continuous monitors. Examples of long-term detectors used in home environment testing include: alpha track detectors and electret chambers.

** Conduct a short-term test in each of the lowest structural areas suitable for occupancy in the home. For example, if the home is a split-level building with one or more foundation types: test in the basement, in a room over the crawlspace and in a slab-on-grade room. In accordance with this protocol, measurement licensees are required to test in each of the foundation types.

(Source: Amended at 37 Ill. Reg. 20240, effective December 9, 2013)