NC Radon Zone Map
Source: The EPA Radon in NC Zone Map (below) is based on indoor radon screening samples compiled by the EPA, geologic and soil analysis, and foundation types to arrive at the zone characterizations.
NOTE: Radon data CAN NOT be used to predict whether a particular building or site will have elevated radon levels. Radon levels are highly site specific. The only way to know the radon level in a building is to conduct a radon test.
Radon Data Map
This map is for educational purposes only and is intended to reflect that radon has been found to be present throughout the State.
NC School Radon Data Set
Based on the Environmental Protection Agency's (EPA) conclusion that ". . . Schools may be a significant source of radon exposure for children and staff . . ." The Environmental Team of NC Radiation Protection Program (NCRP) conducted a pilot radon survey in 20 North Carolina schools during the summer of 1989 and again in the winter of 1990. The results of 400 measurements indicate that the radon levels in school classrooms are similar to regional radon levels found in residential surveys.
EPA has a specific testing strategy for schools If you test a school for radon you should follow these guidelines: test all frequently used rooms on and below the ground level - Because radon levels in schools have been found to vary significantly from room to room; test all frequently-occupied rooms in contact with the ground; and conduct tests in the cooler months of the year.
In 1990 and 1991, the North Carolina Department of Public Instruction (DPI) assisted many schools in North Carolina with purchasing radon canisters for the purpose of measuring classrooms in individual schools. However, test results were never compiled statewide by DPI. Individual schools' test results were retained by each school.
In 1997, North Carolina Radiation Protection (NCRP) retrieved most of the survey data from this previous project. In the spring of 1998, NCRP assisted with radon testing in an additional 35 school districts which had no test data. Five schools per district were tested.
Currently, survey data has been compiled from 1,102 schools, with 23,448 classrooms tested in 94 counties (at least one school per county) out of 100 counties in North Carolina.
The average radon level tested is: 1.79 pCi/l.
Based on NCRP analysis, approximately 11% of these tested classrooms had radon concentrations greater than 4 pCi/l.