Colorado radon zones

  • This map was developed to help state and local organizations target their resources and to help building code officials decide whether radon-resistant features are applicable in new construction.
  • It isn’t intended to be used to determine whether a home in a given zone should be tested for radon.
    • Homes with elevated levels of radon have been found in all parts of the state.
    • All homes should be tested regardless of geographic location.
  • Each county was assigned to one of three zones based on radon potential.
    • Each zone designation reflects the average short-term radon measurement that can be expected to be measured in a building without implementing radon control methods.
    • All of Colorado is in Zone 1, which designates the highest-priority radon zone.