You can install what is called a mitigation system. It is a fan that is installed to create a negative vacuum under your house so that the fan can pull the radon out of your home before your home pulls it in. Your home creates a natural vacuum which pulls the air that is under your slab into your home. the radon is in the ground under your home. once you disturb the ground and build a house you disturb the ground and the radon is brought to the surface of the ground and into your home. Radon is in every home. old, new, remodeled, whatever. it is there. the only home that radon would not be present would be trailors. (no ground contact) Radon is constantly blowing in the air at a 0.3pCi/L. You want to have less than 4.0pCi/l in your home, if you have more you should have a mitigation system installed. for more info feel free to pm me or call 614-560-0297 hope this helps