prEN ISO 13160

Scope

Warning — Persons using this document should be familiar with normal laboratory practice. This document does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user to establish appropriate safety and health practices and to determine the applicability of any other restrictions. Warning — It is absolutely essential that tests conducted according to this document be carried out by suitably trained staff. This document specifies methods to determine 90Sr and 89Sr by liquid scintillation counting (LSC) or proportional counting (PC) in supply water, drinking water, rainwater, surface and ground water, marine water, as well as cooling water, industrial water, domestic, and industrial wastewater after proper sampling, handling and test sample preparation. The detection limit depends on the sample volume, the instrument used, the sample counting time, the background count rate, the detection efficiency and the chemical yield. The method described in this document, using currently available LSC and PC instruments, has a detection limit of approximately 2 mBq·l−1 and 10 mBq·l−1 for 90Sr and 89Sr, respectively, for a volume of 2 l and a measuring time of 60 000 s, which is lower than the WHO criteria for safe consumption of drinking water (100 Bq·l−1 for 89Sr and 10 Bq·l−1 for 90Sr)[4]. The methods described in this document are applicable in the event of an emergency situation. When contamination contains fresh fission products, the contribution of 89Sr to the total amount of radioactive Sr is not negligible. This document provides test methods to determine the activity concentration of 90Sr in presence of 89Sr, and to determine the activity concentration of 90Sr in large volume of water sample (>50 L). The analysis of 90Sr and 89Sr adsorbed to suspended matter is not covered by this method. Filtration of the test sample and a chemical separation are required to separate and purify Sr from a test portion of the sample as the analysis of 90Sr and 89Sr adsorbed to suspended matter is not covered by this method. It is the user’s responsibility to ensure the validity of this test method selected for the water samples tested.