radon retest after repair 4

https://subslabdepressurizationtimes.valiantfield.com/posts/understanding-sub-slab-depressurization-for-radon-mitigation-in-st.-louis

After installing a radon mitigation system, it's crucial to retest your home to ensure the levels dropped below the action limit. Wait at least 48 hours after turning on the fan, and run the test for a minimum of two days during normal living conditions. If the radon still tests high, you may need to adjust the system or add a sealant around foundation cracks.