ISO 5667-20-2008 PDF

Full title and description

Water quality — Sampling — Part 20: Guidance on the use of sampling data for decision making — Compliance with thresholds and classification systems. This International Standard gives principles, basic requirements and illustrative methods for using sampling data to make decisions about whether water quality meets targets or thresholds, has changed, or falls within a grade of a classification system.

Abstract

ISO 5667-20:2008 establishes principles, basic requirements and illustrative methods for dealing with the use of sample data for decision making based on assessment of the confidence that water quality meets targets and complies with thresholds, has changed, or lies in a particular grade in a classification system. It provides guidance on preliminary examination of sensitivity of decisions to error and uncertainty and gives general advice on constraint formulation for thresholds and on the design and scale of sampling programmes (note: it does not attempt to cover the full range of statistical techniques).

General information

• Status: Published (International Standard; confirmed in systematic review).
• Publication date: 7 March 2008 (2008-03).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 13.060.45 (Examination of water in general).
• Edition / version: Edition 1 (2008).
• Number of pages: 34 pages.

Scope

Provides guidance on interpretation and use of sampling results for decision making in water-quality contexts — specifically to assess compliance with thresholds and classification systems, detect changes in quality, and evaluate whether targets are met. The standard covers principles, requirements and illustrative methods for assessing confidence in decisions and offers approaches for preliminary sensitivity checks for error and uncertainty; it does not provide exhaustive statistical methods. Intended to inform the formulation of thresholds/targets and the form and scale of sampling programmes used to support decisions.

Key topics and requirements

• Principles for using sample data to support binary and graded decisions (compliance, classification, trend detection).
• Frameworks for expressing thresholds, targets and decision constraints.
• Assessment of uncertainty and confidence in decisions derived from sampling data.
• Illustrative, pragmatic methods for preliminary sensitivity analysis to error and uncertainty.
• Guidance on matching sampling programme design and scale to the decision being made.

Typical use and users

Used by environmental regulators, water-quality laboratories, environmental consultants, researchers and water-resource managers who need to interpret sample data to support compliance assessments, classification schemes or change detection. It helps programme designers and decision-makers choose sampling approaches and to judge confidence limits and the sensitivity of conclusions to sampling and analytical uncertainty.

Related standards

Part of the ISO 5667 series (Water quality — Sampling). Other relevant parts include guidance on sampling programme design and techniques (Part 1), sampling of rivers and streams (Part 6), sampling of sludges (Part 13) and guidance on suspended solids (Part 17), among other parts addressing particular matrices and sampling situations. National/adopted versions (for example British and Swedish national publications) are commonly available for purchase from national standards bodies.

Keywords

water quality, sampling, decision making, thresholds, classification, uncertainty, confidence limits, sampling programme, sensitivity analysis

FAQ

Q: What is this standard?

A: ISO 5667-20:2008 is an International Standard giving guidance on using sampling data for decision making about water quality — specifically for assessing compliance with thresholds and classification systems and for judging whether water quality has changed or meets targets.

Q: What does it cover?

A: It covers principles, basic requirements and illustrative methods for interpreting sampling results, assessing confidence and sensitivity to error and uncertainty, and for aligning sampling programme design to the decision context. It does not provide a comprehensive set of advanced statistical techniques.

Q: Who typically uses it?

A: Environmental regulators, water-quality laboratories, consultants, researchers and water-resource managers who evaluate monitoring data for compliance, classification, or trend/change detection purposes.

Q: Is it current or superseded?

A: ISO 5667-20:2008 was published on 7 March 2008 and has been subject to ISO's systematic reviews; the ISO catalogue shows the 2008 edition as confirmed (reviewed and confirmed) in the ISO review cycle (confirmation recorded in 2011, 2016 and most recently in 2022), so the 2008 text remains the current International Standard at the time of the ISO record.

Q: Is it part of a series?

A: Yes — it is one part of the ISO 5667 series on water-quality sampling; the series contains multiple parts addressing programme design, sampling techniques for different matrices and specific guidance for rivers, sludges, suspended solids and other sampling situations.

Q: What are the key keywords?

A: Water quality, sampling, decision making, thresholds, classification, uncertainty, confidence, sampling programme.