sub-slab depressurization 5

https://kilo-wiki.win/index.php/Understanding_Radon_Mitigation_Cost_St_Louis_Homeowners_Need_to_Know

Sub-slab depressurization is a fancy term for a simple idea: creating a low-pressure zone under a concrete floor to pull harmful soil gases like radon away from your home. A fan system draws air from beneath the slab and vents it safely outside, preventing those gases from seeping up through cracks. It's a common, effective fix in many basements.