DIN Standards Committee Materials Testing
DIN 25457-1 Beiblatt 1
Activity measurement methods for the clearance of radioactive substances and nuclear facility components - Part 1: Fundamentals; Supplement 1: Explanations
Aktivitätsmessverfahren für die Freigabe von radioaktiven Stoffen und kerntechnischen Anlagenteilen - Teil 1: Grundlagen; Beiblatt 1: Erläuterungen
Overview
This supplement provides explanations regarding the procedure for the clearance of residual substances by measurements of the surface contamination and using material samples, when the approach of conservative calibration in the context of DIN 25457-1:2012-04, 4.1.4 is selected for this purpose instead of a complete consideration of Type A and Type B measurement uncertainties. As the formalism during complete observation of all measurement uncertainties is complex and this procedure furthermore is not used in practice, particularly for the handling of clearance approved in accordance with § 7 StrlSchV, this supplement to DIN 25457-1 deals specially with the procedure with conservative calibration for those measurement methods primarily used for clearances handled as approved in § 7 StrlSchV. This is a direct surface gross activity measurement with surface contamination monitor and sampling with metrological evaluation. The committee responsible for this supplement is NA 062-07-46 AA "Reststofffragen" ("Questions concerning residues") at DIN.
