Overview
ISO 13165-2:2022 - Water quality - Radium-226 - Part 2: Test method using emanometry specifies a standardized analytical procedure to determine the activity concentration of radium-226 (226Ra) in all types of water using emanometry. The method covers determination of soluble, suspended and total 226Ra for samples with soluble activity concentrations greater than 0.02 Bq·L−1. The document includes requirements for sampling, sample preparation, measurement, quality assurance and expression of results, and provides informative annexes (decay chains, bubbler design, and a coated glass scintillation cell).
Key topics and technical requirements
- Scope and applicability
- Measurement of 226Ra in drinking water, surface water, groundwater, seawater, wastewaters and effluents, where soluble 226Ra > 0.02 Bq·L−1.
- Measurement principle
- Emanometry-based technique specified in the standard (principle and procedural elements are described in Clause 4 and procedural Clauses 5–7).
- Sampling and sample handling
- Sampling and storage requirements align with ISO 5667 series guidance to preserve sample integrity before analysis.
- Procedures and instrumentation
- Sample preparation, defined measurement conditions and counting procedures are specified (Clauses 7.1–7.3).
- Informative annexes cover practical apparatus such as a bubbler (Annex B) and a silver-activated zinc sulfide coated glass scintillation cell (Annex C).
- Quality assurance and quality control
- Comprehensive QA/QC programme requirements including influence parameters, instrument verification and calibration, method verification and analyst competence (Clause 8). Laboratories are expected to follow ISO/IEC 17025 for competence.
- Uncertainty and detection limits
- Expression of results covers activity concentration reporting, standard uncertainty, decision threshold, detection limit and coverage intervals in accordance with ISO 11929-series principles (Clause 9).
- Supporting information
- Annex A provides decay chains for uranium and thorium relevant to radium behaviour.
Practical applications and users
- Environmental and water-quality laboratories performing routine radium monitoring.
- Drinking-water utilities and public health agencies verifying compliance with guidance limits.
- Industrial facilities (mining, mineral processing, phosphate industry) monitoring effluents.
- Regulatory bodies, environmental consultancies and emergency response teams assessing radiological impacts.
- Accredited testing laboratories seeking conformity with ISO/IEC 17025 for radionuclide analysis.
Related standards (for implementation)
- ISO 5667 series - Sampling, preservation and handling of water samples
- ISO 11929 - Determination of decision threshold, detection limit and coverage intervals for ionizing radiation measurements
- ISO/IEC 17025 - Competence of testing and calibration laboratories
- ISO 80000-10 - Quantities and units relevant to atomic and nuclear physics
Keywords: ISO 13165-2:2022, radium-226, emanometry, water quality, radium measurement, detection limit 0.02 Bq·L−1, ISO 5667, ISO 11929, ISO/IEC 17025, QA/QC.