active sub-slab depressurization 3

https://radonteststlouiscentral.northstarcolumn.com/posts/why-you-need-a-radon-test-st-louis-homeowners-can-trust

Active sub-slab depressurization pulls radon from beneath concrete floors before it can seep into living spaces. A fan creates steady suction under the slab, venting soil gas safely outside. It's a common fix in homes with high radon readings—quiet, continuous, and effective at cutting indoor concentrations.