Guidelines for water quality grade classification for water reuse
This document provides guidelines for water quality grade classification to help users determine the suitability and quality of the reclaimed water for safe non-potable reuse applications, based on the level of exposure. The intention is to enable the water quality grade to be identified at the point of use.
Lignes directrices pour la classification de la qualité de l’eau en vue de sa réutilisation
Standards Content (Sample)
Guidelines for water quality grade
classification for water reuse
Lignes directrices pour la classification de la qualité de l’eau en vue de
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1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Water quality grade classification for reuse application . 1
4.1 Water quality grade for reuse application . . 1
4.2 Water quality grade classification . 2
5 Display of water quality grades . 5
Bibliography . 6
© ISO 2018 – All rights reserved iii
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This document was prepared by Technical Committee ISO/TC 282, Water reuse, Subcommittee SC 3,
Risk and performance evaluation of water reuse systems.
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The reaffirmation of the importance of water along with food security and energy was a significant
outcome in the actions and the follow-up framework passed at the United Nations Conference on
Sustainable Development (Rio+20). With respect to the management of water resources, essential
actions include the prevention of water contamination, more efficient water usage, and the treatment
and best practices for reuse of wastewater as a water resource by households, industries, and
agriculture, particularly in growing urban areas.
Today, many regions in the world face water shortages, and the feasibility of using reclaimed water to
meet water demands for various purposes is of great interest. On the other hand, the potential health
implications of using reclaimed water is of global concern. This has led to an increasing need to specify
appropriate water quality parameters for specific reclaimed water applications, as well as develop
methods of assessing and managing health risks from both regulatory and application perspectives.
Unless these needs are addressed, opportunities for the development of sustainable and appropriate
reclaimed water applications will be lost.
Health risks associated with the use of reclaimed water occur when users use the reclaimed water
inappropriately without knowing its intended purpose. Therefore, it is important that the reuse
application be clearly identified.
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INTERNATIONAL STANDARD ISO 20469:2018(E)
Guidelines for water quality grade classification for
This document provides guidelines for water quality grade classification to help users determine the
suitability and quality of the reclaimed water for safe non-potable reuse applications, based on the level
of exposure. The intention is to enable the water quality grade to be identified at the point of use.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 20670, Water reuse —