Bridging Radiation Policy and Science

Natural and man-made sources of ionizing radiation have made and continue to make invaluable contributions to society and to individuals. Radiation is part of nature. Natural sources of radiation including radon gas from the earth’s crust and cosmic radiation from outer space account for 80-90 percent of the radiation to which the public is exposed every year. Man-made sources provide hundreds of beneficial uses including medical and dental x rays, nuclear medicine pharmaceuticals, and nuclear power plants. Man-made radiation, used primarily in medical diagnosis and therapy, accounts for 10-20 percent of the public's exposure every year.