Radon Map

Before You Read the Radon Map

Warning! This risk assessment radon map must be considered properly. The different Zones of this map indicate average levels per county. So just because Zone 3 shows low potential don't assume that you must have a low radon level.

Case in point...

I performed a radon mitigation in northern Minnesota in January of 2007. According to the radon gas map below, the upper area of Minnesota where I mitigated this very nervous customer's home is a Zone 2 on the map.

Zone 2 has only a moderate risk. So, "why was she anxious?" you may be asking. Well, her level was 47.2 pCi/L! More than ten times the acceptable level! At 30 pCi/L it's recommended that I wear a respirator when I enter the house!

Every area of the US and Canada has homes with high radon levels.

And don't fall into the trap of thinking that my neighbor's levels are low, so why should I be concerned? All homes should be tested for radon gas!

Zone 1 counties have a predicted average indoor radon screening level greater than 4 pCi/L (pico curies per liter) (red zones) Highest Potential
Zone 2 counties have a predicted average indoor radon screening level between 2 and 4 pCi/L (orange zones) Moderate Potential
Zone 3 counties have a predicted average indoor radon screening level less than 2 pCi/L (yellow zones) Low Potential

As you can see there are large areas of the United States where your chance to have a high radon level are quite high! But remember these are AVERAGE radon levels in any given area. You level may be higher or lower depending on many factors.

It is an absolute given that some levels will be above acceptable levels wherever you live. 

What's an Acceptable Radon Level?

Here's what EPA states in their literature:

"EPA recommends homes be fixed if the radon level is 4 pCi/L (pico Curies per Liter) or more. Because there is no known safe level of exposure to radon, EPA also recommends that Americans consider fixing their home for radon levels between 2 pCi/L and 4 pCi/L."

Test kits are cheap and easy to use, please don't use the radon map to gamble on your level! Be sure about your radon level by testing!


More Radon Pages

Fast Facts  |  How to Test  |  Understanding Radon Levels  |  Health Dangers  |  United States Risk Map  |  Major Risks for Smokers  |  Test Kit Guide


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