What is Radon Gas?
Radon gas is a radioactive, invisible, colorless, and odorless gas that can cause lung cancer. It forms from the natural breakdown of uranium in rocks, soil, and groundwater.
How is Radon Gas Measured?
It is measured in picocuries per liter of air (pCi/L). A pCi/L is a measure of the rate of radioactive decay. The higher the pCi/L, the higher the risk for lung cancer.

- Outdoor air has an average of 0.4 pCi/L. (U.S. average)
- Indoor air has an average of 1.3 pCi/L (U.S. average)
- Utah has an indoor average of 5.3 pCi/L
The only way to determine the Radon level of a home or building is to test for it. This typically includes a simple 48-hour test followed by a laboratory processing the test and providing the results. The results will be given in pCi/L. While no amount of radon gas is considered safe, The World Health Organization recommends homes with 2.7 pCi/L or more be mitigated.
Where is Radon Gas Found?
Radon is found in every state in the United States. The amount varies depending on how much uranium is in the rocks, soil, and water. Utah has one of the highest concentrations of uranium in the United States. Consequently, it has one of the highest concentrations of radon.
Why is Radon Gas Dangerous?
The World Health Organization, the US Department of Health and Human Services, the National Academy of Sciences, and the Environmental Protection Agency have classified radon as a known human carcinogen. This classification is the result of biological and epidemiological evidence showing the relationship between radon exposure and lung cancer in humans.
Radon gas is the #1 cause of lung cancer among nonsmokers and the #2 cause among smokers. An estimated 22,000 people die every year in the United States from radon-induced lung cancer. In Utah, 1 in 3 homes has dangerous radon levels and 6,000 residents have died from radon-induced lung cancer in the past 30 years. New studies also suggest other health risks may be associated with radon including Leukemia.
How is Radon Gas Removed?
The most common and effective way to remove/reduce radon is through a process called Active Soil Depressurization (ASD). This process collects radon under the home’s foundation and draws it through a series of pipes connected to a radon fan that expels the gas to the outside air.
Installing a radon mitigation system should be done by a certified American Association of Radon Scientists and Technologist (AARST) technician. The mitigation system typically takes 3-4 hours to install and most systems can lower the home’s radon levels to 2.0 pCi/L or below.
To learn more about radon mitigation, read Commonly Asked Questions About Radon Mitigation.