EPA radon zones
Idaho radon map: every county's zone
19 of Idaho's 44 counties are EPA radon zone 1 (predicted average above 4 pCi/L), 20 are zone 2 and 5 are zone 3. High readings occur in every zone, so EPA recommends testing every home.
Ada CountyZone 2
Adams CountyZone 3
Bannock CountyZone 2
Bear Lake CountyZone 2
Benewah CountyZone 1
Bingham CountyZone 2
Blaine CountyZone 1
Boise CountyZone 1
Bonner CountyZone 1
Bonneville CountyZone 2
Boundary CountyZone 1
Butte CountyZone 1
Camas CountyZone 1
Canyon CountyZone 2
Caribou CountyZone 2
Cassia CountyZone 2
Clark CountyZone 1
Clearwater CountyZone 1
Custer CountyZone 1
Elmore CountyZone 1
Franklin CountyZone 2
Fremont CountyZone 1
Gem CountyZone 3
Gooding CountyZone 1
Idaho CountyZone 1
Jefferson CountyZone 2
Jerome CountyZone 2
Kootenai CountyZone 1
Latah CountyZone 1
Lemhi CountyZone 1
Lewis CountyZone 3
Lincoln CountyZone 2
Madison CountyZone 2
Minidoka CountyZone 2
Nez Perce CountyZone 3
Oneida CountyZone 2
Owyhee CountyZone 2
Payette CountyZone 2
Power CountyZone 2
Shoshone CountyZone 1
Teton CountyZone 2
Twin Falls CountyZone 2
Valley CountyZone 1
Washington CountyZone 3
How much does radon mitigation cost?
Most single-family systems cost $800 to $2,500 installed, depending on foundation type and how many suction points are needed. A follow-up test confirms the system works.
What do the zones mean?
EPA radon zones describe counties, not houses. Zone 1 counties have a predicted average indoor level above 4 picocuries per liter (pCi/L), Zone 2 between 2 and 4, Zone 3 below 2. Homes with high levels are found in every zone, which is why EPA recommends that every home be tested, and fixed at 4 pCi/L or above.
Idaho cities: water and radon
Source: EPA Map of Radon Zones.