TABLE 1

Variation of Component of Natural Background Radiation Originating from Earth’s Crust in United States and World

Annual Effective Dose (μSv)
RegionCosmic radiationTerrestrial radiationCosmic and terrestrial radiation
Atlantic coast60160230
Rocky Mountains500400900
East, West, and Central460
Average United States270280550
Average worldwide390480870
  • Data from (5,6).