If the fan in a mitigation system is turned on, what is the minimum time frame for testing?

When conducting radon testing in the context of a mitigation system, it is essential to allow sufficient time for the indoor environment to stabilize after a significant change like the activation of a mitigation system's fan. When the fan is turned on, it can alter airflow patterns, pressure differentials, and concentration levels of radon in the home. This stabilization period is crucial for obtaining an accurate radon measurement.

A minimum of 24 hours of testing following the activation of the fan allows the system to adequately reduce radon levels and ensures that the test results reflect the performance of the mitigation system under operational conditions. This timeframe ensures that any fluctuations in radon levels due to initial airflow changes have settled, providing reliable data for assessment.

Testing for less than 24 hours may yield unreliable results, as radon levels might not be sufficiently stabilized, making it difficult to determine the true effectiveness of the mitigation system in reducing radon concentrations.