sub-slab depressurization 9

https://northpixelate.com/s/0a8mSf0UyqFPpoAbYWEe4

Sub-slab depressurization is a method used to keep radon gas from getting into buildings by pulling a slight vacuum beneath the concrete floor. A fan system creates lower pressure under the slab, so soil gases are vented outside instead of seeping up through cracks. It's a practical fix often installed during new construction or retrofitted in basements with a sump hole and piping.