The truth is, any home could have a radon problem, whether it’s in an area with a high radon potential or an area with a low radon potential, or whether it’s old or new, energy-efficient or drafty, built on a slab or built over a basement or crawlspace.  Because it’s a tasteless, odorless, colorless gas, there are no physical signs that will alert you to the presence of radon in a home.  (It doesn’t smell bad, there is no discoloration of the foundation, there are no visible traces of the gas, etc.)  And, there are no warning symptoms to let you know you’re being exposed.  (It doesn’t cause headaches, nausea, fatigue, skin rashes, etc.)  The only way to know whether your home has a problem–or whether you are at risk–is to test! 

EPA worked with the U.S. Geological Survey and the state radon programs to develop a “map of zones” to help identify areas of the U.S. with the potential for elevated indoor radon levels.  Counties were ranked into one of three categories (Zone 1, Zone 2, or Zone 3, with “1” being higher potential and “3” being lower potential) based on indoor radon measurements (i.e., data from the 1987-88 residential radon survey), geology, aerial radioactivity, soil permeability, and foundation type.  Click here to see the EPA Map of Radon Zones – Michigan or click here to see the U.S. Map of Radon Zones.

This Map of Zones was developed to assist national, state, and local organizations in targeting their resources for outreach and education, as well as to assist building code officials in deciding whether radon-resistant features should be incorporated into new construction.  These maps are NOT intended to be used to determine if a home in a given zone should be tested for radon.  Homes with elevated levels of radon have been found in all three zones.  All homes should be tested regardless of geographic location.

While your neighbor’s test results may provide some indication of the potential for a problem in your home, radon levels can vary significantly from lot to lot and home to home.  Don’t rely on your neighbor’s test results to determine your risk.  Test your own home and be certain!