Is it recommended to conduct an additional test in the room(s) adjoining to the outside exhaust location of an active soil depressurization radon reduction mitigation system (ASD)?

Conducting an additional test in the rooms adjoining the outside exhaust location of an active soil depressurization radon reduction mitigation system (ASD) is recommended. This is because the air pressure changes induced by the ASD can affect how radon gas moves within the home. Testing nearby rooms allows for a comprehensive assessment of whether radon levels have been adequately mitigated throughout the space.

Furthermore, it helps ensure that no radon is being drawn into those adjacent rooms via unintended pathways or leaks, which can occur due to the pressure differentials created by the system. By performing additional testing in these areas, you can confirm the efficacy of the mitigation system and ensure that all living spaces are safe from elevated radon levels.