A Review of the Concepts of Exclusion and Exemption

Abstract

The concept of exemption has been widely used in radiological protection. It is part of the regulator's arsenal for applying legislative requirements in a graded fashion, to avoid the expenditure of effort on situations where the return in terms of improvement in protection would otherwise be trivial. Nevertheless, it still remains a controversial matter. Perhaps somewhat surprisingly, it is not so much the dosimetric criteria for exemption that cause debate; it is more the way in which the concept is used; the scenarios employed to calculate derived activity concentrations, and its relationship to the somewhat analogous concept of exclusion. Much of the debate regarding the use of the concept and its relationship with exclusion finds its origin in the national legislative culture that has developed over the years in various countries and the inevitable resistance to keep pace with the evolution of the system of radiological protection as recommended by the International Commission on Radiological Protection and implemented through the International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources. A particular problem has been the full integration into the legislative system of protection of exposures to radiation from sources of natural origin and the degree to which exemption is a relevant concept for dealing with such situations. The purpose of this paper is to attempt to provide some clarity on the two concepts and their practical implementation with a view to encouraging international harmonization and avoiding further unnecessary debate.