Below is a picture from a recent project.
The Radon Fan installed in the townhome attic
This Townhome had Radon levels of 5.1 pCi/l with a peak of 8.4 pCi/l when the clients called us. We installed an interior system to meet Homeowner Association Requirements.
The post mitigation Radon Test showed a new result of 0.6 pCi/l with a peak of 1.5 pCi/l.
That is a significant difference. The readings will continue to improve over time as the area under the slab dries out from the air movement and the air flow from the far corners increase.
