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.
Here's what EPA states in their literature:
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!