ISO 10703:2021
Water quality - Gamma-ray emitting radionuclides - Test method using high resolution gamma-ray spectrometry

Standard No.

ISO 10703:2021

Release Date

2021

Published By

International Organization for Standardization (ISO)

Latest

ISO 10703:2021

Scope

This document specifies a method for the physical pre-treatment and conditioning of water samples and the determination of the activity concentration of various radionuclides emitting gamma-rays with energies between 40 keV and 2 MeV, by gamma-ray spectrometry according to the generic test method described in ISO 20042. The method is applicable to test samples of drinking water, rainwater, surface and ground water as well as cooling water, industrial water, domestic and industrial wastewater after proper sampling, sample handling, and test sample preparation (filtration when necessary and taking into account the amount of dissolved material in the water). This method is only applicable to homogeneous samples or samples which are homogeneous via timely filtration. The lowest limit that can be measured without concentration of the sample or by using only passive shield of the detection system is about 5·10-2 Bq/l for e.g. 137Cs1). The upper limit of the activity corresponds to a dead time of 10 %. Higher dead times may be used but evidence of the accuracy of the dead-time correction is required. Depending on different factors, such as the energy of the gamma-rays, the emission probability per nuclear disintegration, the size and geometry of the sample and the detector, the shielding, the counting time and other experimental parameters, the sample may require to be concentrated by evaporation if activities below 5·10-2 Bq/l need to be measured. However, volatile radionuclides (e.g. radon and radioiodine) can be lost during the source preparation. This method is suitable for application in emergency situations.

ISO 10703:2021 Referenced Document

• ISO 3696 Water for analytical laboratory use; Specification and test methods
• ISO 5667-1 Water quality — Sampling — Part 1: Guidance on the design of sampling programmes and sampling techniques*， 2023-03-14 Update
• ISO 5667-3 Water quality*， 2024-02-01 Update
• ISO/IEC 17025 General requirements for the competence of testing and calibration laboratories [Standard in French]

ISO 10703:2021 history

• 2021 ISO 10703:2021 Water quality - Gamma-ray emitting radionuclides - Test method using high resolution gamma-ray spectrometry
• 2007 ISO 10703:2007 Water quality - Determination of the activity concentration of radionuclides - Method by high resolution gamma-ray spectrometry
• 1997 ISO 10703:1997 Water quality - Determination of the activity concentration of radionuclides by high resolution gamma-ray spectrometry