How should the house be prepared for a radon test?
Providing “closed house conditions” during short-term tests means that all windows are kept closed, and doors are kept closed except for normal entry and exit. Heating and air conditioning units can be operated as long as they do not introduce outside air. Exhaust or attic fans should not be used. These conditions should be maintained for twelve hours prior to initiation of the test, then throughout the remainder of the test.
