sub-slab depressurization York 3
https://myradonreductionolderhomesplus.meridiannest.com/posts/how-to-approach-radon-reduction-in-older-homes-without-overthinking-it
When we did the sub-slab depressurization York, we basically pulled soil gas from under the concrete using a fan and vented it outside, so it couldn't seep into the living space. It made a big difference in indoor air quality, especially because radon levels dropped significantly afterward.