Mini sump systems are installed through the footings of the building to help radon reduction. A fan is connected to draw the radon out before it enters the building.
Briefly, this process is achieved through drilling hole(s) into a solid floor to extract the radon polluted air. It’s incredibly effective and highly recommended as a solution to reduce the levels of radon in your property.
If you love technical details and want to know more about this process, we recommend you take a look at the BRE website.