Radon in Western North Carolina
According to the EPA, the highest levels of radon in North Carolina are primarily found in Western North Carolina. High radon levels in the soil are a natural part of the local geology. These unique conditions in Western North Carolina lend themselves to higher radon levels in homes. In fact, six of the eight counties with the highest radon levels in North Carolina are located in the mountains. While radon can be present in any home, and all homes should be tested, Asheville, Hendersonville and much of the surrounding areas are regarded as Zone 1 counties. This means that radon levels of 4 pCi/L or higher are present in higher numbers than average. Zone 1 counties are shown in red on the map below.
In the North Carolina mountains, many other counties are categorized as Zone 2, meaning that the average indoor radon screening levels will be between 2 and 4 pCi/L.
Testing is encouraged for all homes, schools, and businesses, and remediation is necessary for buildings in which the levels surpass 4 pCi/L. In addition, structures with levels between 2 and 4 pCi/L should also be considered for treatment. In addition, testing should be conducted regularly, as levels can change dramatically. Ideally, homes and other structures should be checked twice a year – once in the winter and again in the summer.
Zone 1: Highest Potential: counties have a predicted average indoor radon screening level greater than 4 pCi/L (pico curies per liter)
Zone 2: Moderate Potential: counties have a predicted average indoor radon screening level between 2 and 4 pCi/L
The Map of Radon Zones was developed in 1993 to identify areas of the U.S. with the potential for elevated indoor radon levels. The map is intended to help governments and other organizations target risk reduction activities and resources. The Map of Radon Zones should not be used to determine if individual homes need to be tested. No matter where you live, test your home for radon—it’s easy and inexpensive. Fix your home if your radon level is 4 picocuries per liter (pCi/L) or higher. Consider fixing if your level is between 2 and 4 pCi/L.
The Map of Radon Zones was developed using data on indoor radon measurements, geology, aerial radioactivity, soil parameters, and foundation types. EPA recommends that this map be supplemented with any available local data in order to further understand and predict the radon potential for a specific area.[/box]
Source: Map of Radon Zones in North Carolina based on Environmental Protection Agency (EPA) data (http://www.city-data.com/radon-zones/North-Carolina/North-Carolina.html)