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Where Does Radon Come From?

Radon is found throughout Wisconsin.

Radon is a radioactive gas that is found across the state of Wisconsin and travels only a meter or two through soil from where it was created. Radon comes naturally from uranium through a long series of radioactive transformations, meaning it undergoes radium decay before it is transformed into a chemically reactive atom.

Radon enters basements as the air tends to be at lower pressure than the soil gases under the slab. Cracks and openings in basements allow the radon to enter the home.

The Bottom Line:
Radon, a radioactive gas, comes from the natural breakdown of uranium in the ground.

Get your home tested to see if you should take action to reduce the level of radon.

Soil and geology impacts how radon moves

The soil under and around a house is usually the source of indoor radon. Uranium naturally exists in soil and bedrock, and radon is created when uranium decays. Radon can travel through air pockets in the soil and into your house.

Additionally, uranium, radium and other elements in the decay chain can dissolve into water and concentrate; however, the risk is much lower when radon is in water than when it is in the air.

House construction impacts radon's ability to enter homes

House construction (openings to soil) is another variable factor of indoor radon. Radon can enter the home through cracks in the foundation. Learn how to reduce the level of radon in your home and get your home tested!

Want more research?

Various research projects have been done on radon, from how it travels to how it impacts humans. The links below are just a few places you can go for more information.

Last revised March 5, 2021