Radon in North Carolina
Radon in North Carolina varies from house to house, so the county figures below describe areas, not homes. EPA places 8 of the state's 100 counties in Zone 1, its highest band of predicted indoor radon, where about 6% of residents live; 61 are in Zone 3. On the water side, EPA has recorded health-based violations at 419 of the state's 1,978 community water systems since 2016.
What North Carolina's radon program offers
North Carolina has no requirement to test for radon or to mitigate it in schools, child care facilities or any other buildings.
Under Session Law 2023-91 and rule 10A NCAC 15 .1801, organizations that certify radon professionals may apply for state approval and be listed, but approval is optional.
North Carolina does not license radon testers or mitigators; the program lists three approved certification bodies (Inspector Nation Advanced Certifications, NRSB and NRPP) and links to their lists of certified professionals.
Read on North Carolina Department of Health and Human Services, NC Radon Program pages, checked 2026-10-29: state radon program.
Radon in North Carolina by county
The North Carolina radon map below groups counties by EPA zone; zones predict North Carolina radon levels from geology and past surveys and are not home measurements. The largest county, Wake County (1,232,444 residents), is in Zone 2.
| County | Residents | Water systems | Violations since 2016 | Unresolved |
|---|---|---|---|---|
| Alleghany County | 11,379 | 4 | 1 | 0 |
| Buncombe County | 279,210 | 32 | 23 | 1 |
| Cherokee County | 30,373 | 7 | 2 | 0 |
| Henderson County | 120,771 | 35 | 10 | 0 |
| Mitchell County | 15,030 | 5 | 1 | 0 |
| Rockingham County | 93,517 | 35 | 21 | 3 |
| Transylvania County | 34,103 | 20 | 9 | 0 |
| Watauga County | 54,997 | 27 | 18 | 0 |
| County | Residents | Water systems | Violations since 2016 | Unresolved |
|---|---|---|---|---|
| Alexander County | 36,693 | 8 | 0 | 0 |
| Ashe County | 27,266 | 11 | 8 | 0 |
| Avery County | 17,811 | 18 | 9 | 0 |
| Burke County | 88,545 | 17 | 4 | 0 |
| Caldwell County | 80,739 | 12 | 3 | 0 |
| Caswell County | 22,363 | 5 | 15 | 0 |
| Catawba County | 167,054 | 82 | 5 | 0 |
| Clay County | 12,042 | 5 | 1 | 1 |
| Cleveland County | 102,194 | 7 | 6 | 0 |
| Forsyth County | 398,143 | 15 | 1 | 0 |
| Franklin County | 79,771 | 20 | 16 | 0 |
| Gaston County | 242,010 | 142 | 27 | 2 |
| Graham County | 8,179 | 6 | 0 | 0 |
| Haywood County | 63,048 | 10 | 6 | 0 |
| Iredell County | 206,361 | 55 | 5 | 0 |
| Jackson County | 45,281 | 37 | 11 | 0 |
| Lincoln County | 97,611 | 11 | 1 | 0 |
| Macon County | 38,717 | 29 | 12 | 0 |
| Madison County | 22,352 | 4 | 0 | 0 |
| McDowell County | 45,269 | 22 | 13 | 3 |
| Polk County | 20,320 | 7 | 2 | 1 |
| Rutherford County | 65,587 | 15 | 6 | 1 |
| Stokes County | 45,857 | 7 | 7 | 0 |
| Surry County | 71,547 | 35 | 4 | 0 |
| Swain County | 13,945 | 6 | 4 | 0 |
| Vance County | 42,337 | 8 | 11 | 0 |
| Wake County | 1,232,444 | 326 | 69 | 3 |
| Warren County | 19,081 | 14 | 4 | 0 |
| Wilkes County | 66,186 | 10 | 3 | 0 |
| Yadkin County | 37,995 | 12 | 5 | 0 |
| Yancey County | 18,993 | 3 | 0 | 0 |
| County | Residents | Water systems | Violations since 2016 | Unresolved |
|---|---|---|---|---|
| Alamance County | 183,040 | 30 | 4 | 2 |
| Anson County | 22,432 | 8 | 6 | 0 |
| Beaufort County | 44,576 | 7 | 10 | 0 |
| Bertie County | 16,939 | 5 | 1 | 0 |
| Bladen County | 29,777 | 8 | 5 | 0 |
| Brunswick County | 167,112 | 8 | 2 | 0 |
| Cabarrus County | 244,925 | 38 | 41 | 0 |
| Camden County | 11,184 | 1 | 0 | 0 |
| Carteret County | 70,259 | 30 | 15 | 0 |
| Chatham County | 83,874 | 20 | 8 | 0 |
| Chowan County | 13,891 | 2 | 21 | 0 |
| Columbus County | 50,054 | 15 | 6 | 0 |
| Craven County | 104,167 | 12 | 5 | 0 |
| Cumberland County | 338,430 | 31 | 12 | 0 |
| Currituck County | 32,278 | 7 | 1 | 0 |
| Dare County | 38,183 | 7 | 0 | 0 |
| Davidson County | 177,809 | 6 | 11 | 0 |
| Davie County | 45,383 | 3 | 4 | 0 |
| Duplin County | 50,539 | 13 | 8 | 0 |
| Durham County | 343,628 | 21 | 1 | 0 |
| Edgecombe County | 49,124 | 8 | 19 | 0 |
| Gates County | 10,299 | 1 | 0 | 0 |
| Granville County | 61,544 | 8 | 14 | 0 |
| Greene County | 20,671 | 8 | 2 | 0 |
| Guilford County | 558,816 | 92 | 15 | 1 |
| Halifax County | 46,992 | 8 | 20 | 0 |
| Harnett County | 146,096 | 9 | 2 | 0 |
| Hertford County | 19,169 | 8 | 2 | 0 |
| Hoke County | 55,382 | 8 | 2 | 0 |
| Hyde County | 4,583 | 2 | 0 | 0 |
| Johnston County | 249,794 | 47 | 31 | 0 |
| Jones County | 9,462 | 3 | 1 | 0 |
| Lee County | 68,537 | 6 | 4 | 0 |
| Lenoir County | 55,332 | 8 | 0 | 0 |
| Martin County | 21,523 | 10 | 3 | 0 |
| Mecklenburg County | 1,206,285 | 30 | 1 | 0 |
| Montgomery County | 26,364 | 10 | 43 | 0 |
| Moore County | 108,417 | 27 | 68 | 0 |
| Nash County | 97,990 | 16 | 15 | 0 |
| New Hanover County | 243,333 | 16 | 14 | 0 |
| Northampton County | 16,580 | 14 | 4 | 0 |
| Onslow County | 212,954 | 17 | 9 | 0 |
| Orange County | 152,877 | 29 | 18 | 0 |
| Pamlico County | 12,550 | 2 | 1 | 0 |
| Pasquotank County | 41,418 | 4 | 0 | 0 |
| Pender County | 70,077 | 11 | 31 | 0 |
| Perquimans County | 13,460 | 3 | 4 | 0 |
| Person County | 40,143 | 2 | 0 | 0 |
| Pitt County | 180,783 | 14 | 6 | 0 |
| Randolph County | 148,389 | 33 | 21 | 1 |
| Richmond County | 41,990 | 4 | 27 | 0 |
| Robeson County | 118,624 | 12 | 10 | 0 |
| Rowan County | 153,384 | 41 | 16 | 0 |
| Sampson County | 60,404 | 16 | 1 | 0 |
| Scotland County | 33,898 | 8 | 2 | 0 |
| Stanly County | 67,326 | 13 | 24 | 0 |
| Tyrrell County | 3,517 | 2 | 1 | 0 |
| Union County | 263,386 | 6 | 7 | 0 |
| Washington County | 10,654 | 4 | 12 | 0 |
| Wayne County | 120,338 | 11 | 8 | 0 |
| Wilson County | 79,958 | 11 | 12 | 0 |
North Carolina tap water: violations and PFAS
North Carolina has 1,978 active community water systems serving about 9,718,775 people. Since January 2016, EPA has recorded at least one health-based violation at 419 of them (32% of the people served), and 19 have one still listed as unresolved. The most frequent cause was the revised lead and copper rule, at 271 systems, followed by total trihalomethanes, a byproduct of chlorine disinfection (74) and haloacetic acids, a byproduct of chlorine disinfection (43).
EPA tested 284 North Carolina systems for PFAS between 2023 and 2025. 114 had a PFOA or PFOS result above the 4 ng/L limit that applies from 2029; the highest was Town of Nashville at 490 ng/L.
Records: EPA Map of Radon Zones, EPA ECHO drinking water data (2026Q3), EPA UCMR 5, North Carolina Department of Health and Human Services, NC Radon Program, US Census Bureau Vintage 2024. How zones and violations are counted: methodology · all states.