Is radon high where you live? EPA zones by county
EPA's Map of Radon Zones rates every county by its predicted average indoor radon level. Zone 1 is highest. EPA says any home can have high radon and every home should be tested, so use the zone as a guide, not an answer.
This site is growing. New records are added every day once they are checked against official sources. 2568 counties published so far.
By state
- Alabama (58)
- Alaska (6)
- Arizona (15)
- Arkansas (73)
- California (37)
- Colorado (61)
- Delaware (3)
- Florida (41)
- Georgia (142)
- Hawaii (4)
- Idaho (31)
- Illinois (91)
- Iowa (94)
- Kansas (104)
- Kentucky (93)
- Louisiana (59)
- Maine (13)
- Maryland (19)
- Massachusetts (11)
- Michigan (70)
- Minnesota (77)
- Mississippi (69)
- Missouri (111)
- Montana (51)
- Nebraska (92)
- Nevada (13)
- New Hampshire (10)
- New Jersey (18)
- New Mexico (32)
- New York (54)
- North Carolina (75)
- North Dakota (52)
- Ohio (88)
- Oklahoma (73)
- Oregon (31)
- Pennsylvania (62)
- Rhode Island (5)
- South Carolina (46)
- South Dakota (65)
- Tennessee (74)
- Texas (224)
- Utah (26)
- Vermont (13)
- Washington (38)
- West Virginia (54)
- Wisconsin (67)
- Wyoming (23)