Kommittébeteckning: SIS/TK 424 (Kemiska vattenundersökningar)
Källa: CEN
Svarsdatum: den 20 sep 2019
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This document provides guidelines to enable testing laboratory using rapid test methods on all types of water samples that may be contaminated following a nuclear or radiological emergency situation:

— taking into account the specific context for the tests to be performed, e.g. an unknown and potentially unusual high level of contamination;

— using or adjusting, when possible, radioactivity test method implemented during routine situation to obtain a result rapidly or applying specific rapid test methods previously validated by the laboratory, e.g. for 89Sr determination;

— preparing the test laboratory to measure a large number of potentially contaminated samples.

The aim of this document is to ensure decision makers have reliable results needed to take actions on time and minimize the dose to the public.

Measurements are performed in order to minimize the risk for the public in checking the water quality of water supplies. For emergency situations, test results are compared to operational intervention levels.

Note Operational intervention levels (OILs) are derived from IAEA Safety Standards[13] or national authorities[5].

A key can be to use the usual and routine methods in a faster manner. The goal of these rapid measurements is often to check an unusual radioactivity level in the test sample, to identify the radionuclides and their activity concentration levels and to establish compliance of the sampled water with intervention levels[21]. It should be noted that in such circumstances validation parameters are not always valid (impossible use of standard measuring geometries for gamma spectrometry…) and thus uncertainties associated with the test results may increase.

The first steps of the analytical approach is usually based on gross alpha and gross beta test methods considered as screening methods (adaptation of ISO 10704 and ISO 11704) and gamma spectrometry (adaptation of ISO 20042, ISO 10703 and ISO 19581). Then, when necessary[3], test method standards for specific radionuclides are adapted and applied (for example, 90Sr measurement following ISO 13160) as proposed in Annex A.

This document refers to a set of already published ISO standards. When appropriate, this document also refers to national standards or other publically available documents.

Screening techniques that can be carried out directly in the field are not part of this document.