Optimization of measurement techniques for very low-level radioactive waste material
Relative radiotoxicities of all relevant waste nuclides are defined and calculated according to the limits set by the German Radiation Protection Ordinance. The hard-to-detect nuclides (e.g. Fe-55, Ni-59, Ni-63) are found to be of minor radiological relevance, even if their abundance in certain waste categories is predominant. Standard beta or gamma measurements are sufficient if alpha contamination can be excluded. Twenty different detectors were tested and their suitability for release measurements, i.e. detection efficiencies, limits of detection and minimum measuring times, were determined using standards of C-14, Pm-147, Co-60, Cs-137, Sr-90/Y-90, Cr-51 and Am-241 in 5 geometries representative of contaminated waste material. In most geometries, proportional counters were found to be adequate for release measurements, while for detection of alpha radiation in difficult geometries, small detectors (i.e. surface barrier detectors, photodiodes or Geiger-Müller counters) are needed.
Bibliographic Reference: EUR 13307 EN (1991) 88 pp., FS, ECU 8.75
ISBN: ISBN 92-826-2397-1
Record Number: 199110545 / Last updated on: 1994-12-02
Original language: en
Available languages: en