ISO TS 21231-2019 PDF
Name in English:
St ISO TS 21231-2019
Name in Russian:
Ст ISO TS 21231-2019
Original standard ISO TS 21231-2019 in PDF full version. Additional info + preview on request
Full title and description
Water quality — Characterization of analytical methods — Guidelines for the selection of a representative matrix. This technical specification gives guidance on selecting representative matrices and materials suitable for evaluating the performance characteristics (including uncertainty) during the initial assessment of quantitative analytical methods used in physico‑chemical water analysis.
Abstract
ISO/TS 21231:2019 specifies representative materials and selection criteria to determine method performance characteristics (accuracy, precision, bias, uncertainty, limits of quantification, etc.) for laboratories performing physico‑chemical analyses of water. The document details five main categories of water (waters intended for consumption, natural waters, waste waters, marine waters and recreational waters) and explains how to choose a matrix compatible with the samples handled.
General information
- Status: Published (confirmed as current following systematic review).
- Publication date: 5 February 2019 (Edition 1, 2019).
- Publisher: International Organization for Standardization (ISO).
- ICS / categories: 13.060.50 — Examination of water for chemical substances.
- Edition / version: Edition 1 (2019).
- Number of pages: 34 pages (document length as published by ISO).
Scope
The Technical Specification provides guidance for selecting a representative matrix or material suitable for determining the performance characteristics (including uncertainty) during the initial assessment of a quantitative analytical method used in laboratories for physico‑chemical water analysis. It is focussed on five primary water types — drinking/consumable waters, natural waters, waste waters, marine waters and recreational waters — but allows incorporation of other specific types where justified and compatible with sample characteristics.
Key topics and requirements
- Definition of "representative matrix" and criteria for matrix selection for method assessment.
- Guidance on selecting materials for determining method performance characteristics (trueness, precision, limits, measurement uncertainty, etc.).
- Coverage of five principal water categories: waters intended for consumption, natural waters, waste waters, marine waters and recreational waters.
- Recommendations on matrix compatibility with the analytes and sample handling procedures.
- Reference and cross‑check to related ISO Guides and standards used in method validation and reference material production (e.g., ISO Guide 35, ISO 5725 series, ISO 17034).
Typical use and users
Used by environmental and water testing laboratories, method developers, laboratory quality managers, accreditation bodies and regulatory authorities to select appropriate matrices and materials for method validation and initial performance assessment. It supports consistent, reproducible method evaluation in laboratories conducting physico‑chemical analyses of different water types.
Related standards
Cross‑references and related documents commonly used with ISO/TS 21231:2019 include ISO 6107 (vocabularies), ISO 5667‑3 (sampling), ISO/TS 16489, ISO 5725 (accuracy of measurement methods), ISO Guide 35 (reference materials), ISO/TS 13530, ISO 11352, EN 12457 (leaching tests), ISO Guide 80 and ISO 17034, as well as relevant ASTM and regional standards cited for specific matrices and procedures. These cross references help integrate matrix selection with sampling, reference material production and method validation workflows.
Keywords
water quality; representative matrix; analytical methods; method validation; measurement uncertainty; physico‑chemical analysis; reference materials; performance characteristics; ISO/TC 147.
FAQ
Q: What is this standard?
A: ISO/TS 21231:2019 is an ISO Technical Specification titled "Water quality — Characterization of analytical methods — Guidelines for the selection of a representative matrix" that provides guidance on choosing representative matrices for initial method performance assessment in physico‑chemical water analysis.
Q: What does it cover?
A: It covers selection criteria and guidance for representative materials/matrices used to determine method performance characteristics (accuracy, precision, uncertainty, limits of detection/quantification, etc.) and addresses five main water categories (waters intended for consumption, natural waters, waste waters, marine waters and recreational waters).
Q: Who typically uses it?
A: Environmental and water testing laboratories, method developers, quality managers, accreditation bodies and regulatory agencies use this TS when planning method validation and initial performance assessments for physico‑chemical analyses.
Q: Is it current or superseded?
A: As published in February 2019 (Edition 1) ISO/TS 21231 was systematically reviewed and confirmed in 2022; the ISO record indicates this version remains current following that review. When using the standard for compliance or accreditation, always verify the current status with the issuing body or your national adoption.
Q: Is it part of a series?
A: It is a standalone Technical Specification within the ISO/TC 147/SC 2 remit on water quality and analytical methods; it is commonly used alongside other ISO standards and guides on sampling, method validation and reference materials (see "Related standards" above).
Q: What are the key keywords?
A: Key keywords include representative matrix, water quality, method characterization, method validation, measurement uncertainty, reference material, physico‑chemical analysis.