Radon Banner


The U.S. Surgeon General recommends ALL homes be tested for radon gas.


Radon Test Kit

Test Your Home For Radon Today!

Individuals can check radon levels at their home using a kit or through the services of a qualified radon mitigation professional. Testing kits are available at many local hardware and building stores. 

Short-term test kits are also available from the Winnebago County Health Department for the discounted rate of $10 per kit. The cost of each kit includes return postage and certified lab analysis. Kits can be purchased by calling 815-720-4100.

Please note that at this time, due to COVID-19, appointments are needed for all Health Department Services.    Please call 815-720-4100 to purchase your radon test kit and arrange for curb-side pickup.


What Is Radon?

Radon is naturally occurring gas that forms when uranium, radium and thorium break down in rocks, soil, and groundwater. Radon cannot be seen, tasted, or smelled.



Where Is Radon Found?

As radon comes naturally from the earth, radon is found in the air around us. However, when radon gas from underneath a home or building leaks into the home or building through gaps or cracks, too much of it can build up inside.  Radon can also dissolve into the water supply and could add to the radon gas present in a home depending on the water source.


Is Radon Dangerous?

Breathing in radon gas can cause health problems and is estimated to be the second leading cause of lung cancer in the United States. When you breathe in radon, radioactive particles from the radon gas become trapped in your lungs. Over time, these radioactive particles increase the risk of lung cancer, though it may take years for health problems to appear. According to the U.S. Environmental Protection Agency (EPA) radon gas is responsible for over 20,000 lung cancer deaths each year. People who smoke and are exposed to radon are at even greater risk of developing lung cancer.

1 out of 15


Why Should I Be Concerned?

Nearly one out of every 15 homes in the United States is thought to have high radon levels. High radon levels can be found anywhere in any state. Both old and new homes, those with and without basements can have radon problems.  Even houses next door to each other may have very different radon levels. The only way to know for sure if you have high levels of radon is by testing your home.

According to a study conducted by the Illinois Emergency Management Agency (IMEA), 41 percent of homes tested for radon in Illinois had levels higher that the action level of 4.0 picoCuries per liter (pCi/l). To view state radon data by county click here.


How Does Radon Enter A Home Or Building?

Radon Entry Ways

There are many ways radon can find its way into your home or building:

  1. Cracks in solid floors
  2. Construction joints
  3. Cracks in walls
  4. Gaps in suspended floors
  5. Gaps around service pipes 
  6. Cavities inside walls
  7. The water supply
See photo at right for corresponding illustration.

Radon in Soil - Radon gets into the indoor air primarily through pores and cracks in the soil under homes and other buildings.  Because the air pressure in homes and buildings is generally lower than the pressure in the soil around or underneath the foundations, the difference in pressure creates suction. Radon will come through cracks, even at low levels due to the suction.

Radon in Water - Radon gas can be present in water that comes into your home.  If your home's water supply is from underground sources, such as wells, radon can escape from the water during everyday activities such as drinking, washing dishes, cooking and showering.  If radon is present in the water coming into your home, these everyday actions can make a small contribution to the radon gas present in the air in your home.


What Should I Do To Ensure My Home Is Safe From High Levels Of Radon?

Having your home tested is the only effective way to determine whether you or your family are at risk of high radon exposure. If testing shows high levels of radon gas you can fix it with mitigation measures. 


Mitigation Professional

What Happens If My Home Has High Levels of Radon?

Testing is the only way to know if there are high levels of radon gas in your home.  If the results of your test show high levels of radon gas in you home, there are steps you can take to reduce the levels such as having a radon mitigation system installed in your home to disperse the radon gas and reduce exposure and protect the health of you and your family.


 Additional Resources on Radon?