Section 422.APPENDIX B Recommended Testing Strategy for Measurements in Buildings Involved in Real Estate Transactions

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

Perform a Short-Term Test The minimum length of a short-term test shall be 48 hours.

There are 2 methods that may be used for short-term testing during a Real Estate transaction. (1) Simultaneous Tests – Two short-term tests set side by side conducted simultaneously. (2) Continuous Monitor Testing – A Continuous Monitor that measures in hourly increments.


	If the result is less than 4.0 pCi/L	If the result is 4.0 pCi/L or more

	No further action is required. Retest in two years or if any renovations or additions are made to the building.	Fix the home.

* Short-term tests may last between 2 and 90 days, most last between 2 and 7 days. Tests between seven and 90 days are usually impractical for real estate transactions but are fine for homeowners assessing their own radon situation. Examples of short-term detectors used in home environment testing include: activated charcoal canisters, charcoal liquid scintillation vials, electret chambers and continuous monitors.

** 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 professionals are required to test in each of the foundation types.

(Source: Amended at 33 Ill. Reg. 14479, effective October 9, 2009)