Application of the ICRP recommendations to revised secondary radiation protection standards

In 1977, the International Commission on Radiological Protection (ICRP) issued Publication No. 26 containing its recommendations for major changes in the conceptual basis for radiation protection. The new recommendations consider total risk (to the whole body) instead of controlling (critical-organ) risk. Subsequent publications and explanatory statements most useful for providing clarification of the intent of the new recommendations have not resolved practical problems encountered in attempting to apply them to either occupational or public exposures. Some of the problems that still exist in applying these recommendations for estimating doses to members of the public include the following: allowance for age differences within an exposed population group, definition of 50-y dose versus lifetime (70-y) dose, definition of negligible risk levels for individual and collective doses, and derivation of appropriate concentration guidelines. The United States is in the process of adopting the revised recommendations of the ICRP. In addition to adopting versions of the primary radiation protection standards, both the U.S. Nuclear Regulatory Commission and the U.S. Department of Energy have developed draft secondary standards that are similar to the Derived Air Concentration values given by the ICRP. This paper presents a brief history of the development of these revised secondary standards, discusses their technical bases, provides a comparison of them, and discusses their limitations and potential misapplication.