Frequently Asked Questions

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 Radon is a colorless, odorless radioactive gas that naturally forms as uranium, thorium, and radium break down in soil, rock, and groundwater. It can enter homes through foundation cracks, gaps, and crawl spaces where it builds up indoors. While small amounts exist everywhere, higher concentrations indoors can pose serious health risks, making radon testing and mitigation essential for safe indoor air. 

 Radon-222 forms as radium-226 breaks down, both of which are part of the natural uranium-238 decay chain. Because uranium is found throughout the earth’s crust, radium-226 and radon-222 exist in nearly all soils, rocks, and groundwater. Radon levels in soil vary widely, often measuring from hundreds to several thousand picocuries per liter (pCi/L). How much radon enters a home depends on factors like soil type, porosity, moisture, weather, and the home’s air pressure. 

Radon is an invisible, radioactive gas created by the natural breakdown of uranium found in most soils. It moves upward from the ground and can seep into homes through foundation cracks, gaps, and other openings. Once inside, radon can accumulate to unsafe levels because homes trap the gas indoors. Any house—new or old, sealed or drafty, with or without a basement—can have elevated radon levels. While soil gas is the primary source, radon can also enter through well water. 

 Radon is present everywhere—in both outdoor air and inside buildings. While outdoor levels are generally low (around 0.4 pCi/L), radon can build up indoors to much higher concentrations. The EPA advises taking action if your home tests at or above 4 pCi/L (150 Bq/m³), and even recommends considering mitigation between 2–4 pCi/L (75–150 Bq/m³), since no level of radon exposure is completely risk-free. The average U.S. home has about 1.3 pCi/L of radon, and based on this, the EPA estimates radon contributes to roughly 21,000 lung cancer deaths each year. 

 Radon mitigation systems are highly effective—many can lower radon levels in a home by as much as 99%. In most cases, reducing radon is comparable in cost to other common household repairs, though the final price depends on your home’s size, layout, and the system installed. The best way to know your exact cost is to request a quote from a certified radon mitigation contractor. Across the U.S., hundreds of thousands of homeowners have successfully lowered radon levels and made their homes safer. 

 Radon gas is much heavier than air—about 7.5 times denser—yet it moves easily with changes in air pressure and circulation. In homes with forced air heating or cooling, radon can spread quickly throughout the entire living space. That’s why mitigation systems are designed to vent radon above the roofline, where concentrations drop sharply within just a few feet of the discharge point, returning to normal background levels. The EPA does not allow ground-level venting because radon could be pulled back into the home or expose people nearby, especially children. At the discharge point, levels can reach tens of thousands of picocuries per liter, making proper vent placement essential for safety. 

• You should test your home or office every 2 years.  
• If your home or office has never been tested, do so immediately.  
• If there is new construction, or renovations being done, test before and after.
• If there is increased use of a lower level, such as converting a basement to a bedroom, office or workshop, test the area to see the Radon levels that you can be exposed to with more time spent in the new area.
• If you are buying or selling a residential home, test before the sale.