Radon Gas

Radon GasRadon is a naturally occurring, invisible, odorless gas that is harmlessly dispersed in outdoor air, but when trapped in buildings can reach harmful elevated levels. Radon is thought to cause up to 22,000 lung cancer deaths each year in the United States.

Radon gas originates when uranium breaks down giving off a radioactive gas. Since small amounts of uranium are common in many Wisconsin soils, radon is also common in Wisconsin's homes. While radon is more common in some areas of the state than others, radon levels high enough to cause concern have been found in homes in all Wisconsin counties.

Radon gas diffuses, as does any gas, by flowing along the path of least resistance to the earth's surface and then to the atmosphere. Common entry paths for radon include earth floors, sump pump wells, floor drains, and gaps in floors and around pipes, visible and microscopic cracks, holes left from form ties, construction joints and hollow concrete block walls.

Radon does not cause direct respiratory problems, headaches or other immediate health problems. However, prolonged exposure increases the chances of lung cancer. The EPA has determined that an average lifetime exposure of four pCi/L gives nonsmokers two chances in a thousand of dying from lung cancer. The higher the life time exposure the greater the risk of lung cancer is. The risk to tobacco smokers from radon exposure is dramatically greater.

Radon testing kits are available  at the health department for a  cost of $10.00

A. Cracks in concrete slabs.Diagram of Cross section of house showing areas of vulnerability

B. Spaces behind brick veneer walls that rest on uncapped hollow-block foundations.

C. Pores and cracks in concrete blocks.

D. Floor-wall joints.
E. Exposed soil, as in a sump or crawl space.

F. Weeping (drain) tile, if drained to an open sump.

G. Mortar joints.

H. Loose fitting pipe penetrations.

I. Open tops of block walls.

J. Building materials, such as brick, concrete, rock (shale, granite).

K. Well water (not commonly a major source in most Wisconsin homes).

Map of Trempealeau county showing all Radon areas
Printable Version

Additional Resources

Contact Us
715-538-2311 ext 220
18600 Hobson Street
Whitehall, WI 54773-8614


Monday - Friday
8:00 AM - 4:30 PM
Closed Major Holidays

Jennifer Comeau
Director of Public Health
Health Officer, Trempealeau County