sub-slab depressurization 4

https://getradonsystemwarrantyfacts.quantlynix.com/posts/what-a-radon-system-warranty-covers-and-why-it-matters

Sub-slab depressurization is a technique used in radon mitigation where a pipe is inserted through the concrete slab of a building's foundation to create a vacuum beneath it. This suction draws soil gases, including radon, away from the structure and vents them safely outside, preventing indoor air contamination. It's a common, effective solution for homes built on slabs.