Arkansas: 75 counties covered
Of 75 rated Arkansas counties, 0 are in EPA's highest radon-potential zone (Zone 1) — but every county page links to testing guidance regardless of zone, because a county rating is a county-wide average, not a reading for any one house.
- Pulaski County
- Benton County
- Washington County
- Faulkner County
- Saline County
- Sebastian County
- Craighead County
- Garland County
- White County
- Lonoke County
- Pope County
- Jefferson County
- Crawford County
- Greene County
- Crittenden County
- Baxter County
- Miller County
- Boone County
- Independence County
- Mississippi County
- Union County
- Hot Spring County
- Carroll County
- Johnson County
- Cleburne County
- Poinsett County
- Columbia County
- St. Francis County
- Ouachita County
- Logan County
- Conway County
- Clark County
- Yell County
- Polk County
- Hempstead County
- Randolph County
- Grant County
- Sharp County
- Ashley County
- Madison County
- Marion County
- Franklin County
- Drew County
- Jackson County
- Lawrence County
- Cross County
- Van Buren County
- Arkansas County
- Sevier County
- Phillips County
- Izard County
- Clay County
- Lincoln County
- Stone County
- Fulton County
- Howard County
- Little River County
- Desha County
- Perry County
- Pike County
- Bradley County
- Scott County
- Chicot County
- Montgomery County
- Lee County
- Nevada County
- Prairie County
- Searcy County
- Cleveland County
- Newton County
- Monroe County
- Dallas County
- Lafayette County
- Woodruff County
- Calhoun County