radon fan installation 4

https://lima-wiki.win/index.php/Understanding_Radon_Mitigation_Cost:_What_Homeowners_in_West_St._Louis_County_Should_Know

Installing a radon fan involves running a pipe from the sump or under the slab, through the attic or outside wall, to a quiet, weatherproof fan unit that vents above the roof line to safely reduce radon gas levels.