Is it true that post-mitigation tests should occur in the lowest livable area above any crawlspace?

Post-mitigation testing is crucial in determining the effectiveness of a radon mitigation system, and it is generally recommended to be conducted in the lowest livable area of the home that is above any crawlspaces. This is because radon is a colorless, odorless gas that typically accumulates in lower areas of a home, such as basements and crawlspaces. Testing in the lowest livable area ensures that the results reflect the air quality where people spend time and that the system has adequately reduced radon levels to safe standards.

By conducting the test in this area, homeowners can ensure that radon levels are below the action level set by health authorities, which is important for health and safety measures. It is also significant to test above crawlspaces, as radon can migrate from these spaces into the living areas above. Therefore, the recommendation to test post-mitigation in the lowest livable space protects the occupants effectively and confirms the mitigation system’s operational success.