Radioactivity Measurements at Regulatory Release Levels

A Task Group Report

ISBN : 92-64-02319-4

The release of radioactive materials from regulatory control is subject to release limits which are often based on published recommendations of international organisations, which aim to minimise radiological risks. The application of the recommendations has thus led to limits being set at very low activity levels. Adequate methods of measurement must be available to demonstrate or verify that the activity levels are lower than the recommended values. Measurements would also have to be made under practical industrial conditions, where various constraints could significantly influence the results. Hence, the costs of activity measurements at extremely low levels on large quantities of equipment with complex geometries could be prohibitively high.

The NEA Co-operative Programme on Decommissioning (CPD) established a special Task Group to study these issues in an analytical and structured manner. This report describes the group’s findings regarding the objectives and methodology for radiological characterisation and the equipment used for measurements. The report also contains case studies from NEA member countries and a critical discussion of different methods and techniques.