SIST EN 16056:2023

Influence of metallic materials on water intended for human consumption - Method to evaluate the passive behaviour of stainless steels and other passive alloys

This document specifies a procedure to evaluate the passive behaviour of stainless steels and other passive alloys used in products intended to come into contact with drinking water.
The passive state is the reason why no relevant amounts of metals are released from such materials into the drinking water. This test is used to verify whether the alloy under consideration is passive under conditions which can occur in drinking waters.
This document is not applicable for product testing. It is only applicable for the assessment of passive behaviour of materials.

Einfluss metallischer Werkstoffe auf Wasser für den menschlichen Gebrauch - Verfahren zur Ermittlung des Passivverhaltens von nichtrostenden Stählen und anderen Legierungen

Dieses Dokument legt ein Verfahren zur Ermittlung des Passivverhaltens von nichtrostenden Stählen und anderen passiven Legierungen fest, die in Produkten eingesetzt werden, die dafür vorgesehen sind, mit Trinkwasser in Kontakt zu kommen.
Der Passivzustand ist der Grund, weshalb keine relevanten Mengen an Metallen aus solchen Werkstoffen in das Trinkwasser abgegeben werden. Diese Prüfung wird angewendet, um zu verifizieren, ob die betreffenden Legierungen unter den Bedingungen, die in Trinkwässern vorliegen können, passiv bleiben.
Dieses Dokument ist nicht für Produktprüfungen anzuwenden. Es ist nur anwendbar für die Bewertung von passiven Werkstoffen.

Influence des matériaux métalliques sur l'eau destinée à la consommation humaine - Méthode d'évaluation du comportement passif des aciers inoxydables et autres alliages passifs

Le présent document spécifie un mode opératoire pour évaluer le comportement passif des aciers inoxydables et autres alliages passifs employés dans des produits destinés à entrer en contact avec de l'eau potable.
C'est en raison de leur passivité que ces matériaux ne relarguent pas de quantités significatives de métaux dans l'eau potable. Cet essai sert à évaluer la passivité de l'alliage à l'étude dans des conditions semblables à celles rencontrées dans l'eau potable.
Le présent document n’est toutefois pas applicable aux essais de produits. Il est uniquement applicable pour l’évaluation du comportement passif des matériaux.

Vpliv kovinskih materialov na pripravo pitne vode - Metoda za ovrednotenje pasivnega vedenja nerjavnih jekel in drugih pasivnih zlitin

Ta dokument določa postopek za vrednotenje pasivnega vedenja nerjavnega jekla in drugih pasivnih zlitin, ki se uporabljajo za gradbene proizvode, namenjene stiku s pitno vodo.
Pasivno stanje je razlog, da se v pitno vodo ne izločijo pomembne količine kovin iz takšnih materialov. Ta preskus se uporablja za preverjanje, ali je obravnavana zlitina pasivna pod pogoji, do katerih lahko pride v pitni vodi.
Dokument se ne uporablja za preskušanje proizvodov. Uporablja se samo za ocenjevanje pasivnega vedenja materialov.

General Information

• Status: Published
• Public Enquiry End Date: 29-Apr-2022
• Publication Date: 17-Aug-2023
• ICS: 13.060.20 - Drinking water
• ICS: 67.250 - Materials and articles in contact with foodstuffs
• Technical Committee: IOVO - Water supply and waste water engineering
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 20-Jun-2023
• Due Date: 25-Aug-2023
• Completion Date: 18-Aug-2023
• Ref Project: EN 16056:2023 - Influence of metallic materials on water intended for human consumption - Method to evaluate the passive behaviour of stainless steels and other passive alloys

Relations

• Replaces: SIST EN 16056:2012 - Influence of metallic materials on water intended for human consumption - Method to evaluate the passive behaviour of stainless steels
• Effective Date: 01-Sep-2023
• Refers: SIST EN 12502-1:2005 - Protection of metallic materials against corrosion - Guidance on the assessment of corrosion likelihood in water distribution and storage systems - Part 1: General
• Effective Date: 28-Jan-2026
• Refers: SIST EN ISO 17475:2008 - Corrosion of metals and alloys - Electrochemical test methods - Guidelines for conducting potentiostatic and potentiodynamic polarization measurements (ISO 17475:2005)
• Effective Date: 28-Jan-2026
• Refers: SIST EN 15664-1:2008+A1:2014 - Influence of metallic materials on water intended for human consumption - Dynamic rig test for assessment of metal release - Part 1: Design and operation
• Effective Date: 28-Jan-2026
• Refers: SIST EN ISO 8044:2020 - Corrosion of metals and alloys - Vocabulary (ISO 8044:2020)
• Effective Date: 28-Jan-2026

Overview

SIST EN 16056:2023 sets out a standardized method to evaluate the passive behaviour of stainless steels and other passive alloys in contact with drinking water. Maintaining materials in a passive state is crucial as it prevents significant metal ion release into water intended for human consumption. This European standard is designed to help materials engineers, water supply industries, and regulatory bodies ensure the continued safety and integrity of water distribution systems by assessing the corrosion resistance and passivity of metallic materials. Notably, this document is intended for the assessment of materials rather than finished products.

Published by the Slovenian Institute for Standardization (SIST), this standard supersedes EN 16056:2012 and expands its scope to include additional passive alloys and sample geometries.

Key Topics

• Passive Behaviour Assessment: Describes a procedure to verify that stainless steels and similar passive alloys remain in a passive state when exposed to typical drinking water conditions.
• Prevention of Metal Release: Highlights the role of the passive layer in minimizing the migration of metals from materials into drinking water.
• Electrochemical Testing: Specifies test methods that focus on electrochemical assessment instead of direct measurement of metal release. The procedure identifies the pitting potential and passive characteristics using controlled laboratory tests.
• Sample Preparation & Test Conditions: Includes guidance on preparing test samples-preferably sheet or plate material-and maintaining controlled chloride content and temperature conditions to simulate common scenarios found in water distribution.
• Applicability: The method is strictly for material assessment and does not serve as a product conformity or approval test.

Applications

SIST EN 16056:2023 is practically valuable in several areas:

• Material Qualification and Selection: Enables manufacturers and suppliers of metallic materials for drinking water applications to demonstrate conformance with regulatory expectations regarding corrosion resistance and health safety.
• Design of Water Distribution Systems: Assists engineers in specifying materials for pipes, tanks, and fittings that will not release harmful levels of metals into potable water.
• Quality Assurance: Provides a reproducible method for laboratories and inspection bodies to assess whether materials like stainless steel and alloys used in water infrastructure remain passive under real-world water chemistry.
• Regulatory Compliance: Supports authorities and organizations in upholding public health standards related to materials in contact with drinking water, in line with European directives and national regulations.

Related Standards

Several other European and international standards are referenced and complement the procedures outlined in SIST EN 16056:2023:

• EN 12502-1:2004: Protection of metallic materials against corrosion - Guidance for assessment of corrosion likelihood in water systems.
• EN 15664-1:2008+A1:2013: Dynamic rig test for assessing metal release from metallic materials in contact with water intended for human consumption.
• EN ISO 8044:2020: Vocabulary for corrosion of metals and alloys.
• EN ISO 17475:2008: Guidelines for performing electrochemical test methods relevant to polarization measurements.

By applying SIST EN 16056:2023, organizations can ensure that selected metallic materials, such as stainless steels and passive alloys used in drinking water systems, maintain their passive behaviour and contribute to safe, high-quality water supply infrastructures. This standard is a critical reference for ensuring material durability, public health protection, and compliance with water quality directives.

Standards Content (Sample)

SLOVENSKI STANDARD
01-september-2023
Nadomešča:
SIST EN 16056:2012
Vpliv kovinskih materialov na pripravo pitne vode - Metoda za ovrednotenje
pasivnega vedenja nerjavnih jekel in drugih pasivnih zlitin
Influence of metallic materials on water intended for human consumption - Method to
evaluate the passive behaviour of stainless steels and other passive alloys
Einfluss metallischer Werkstoffe auf Wasser für den menschlichen Gebrauch - Verfahren
zur Ermittlung des Passivverhaltens von nichtrostenden Stählen und anderen
Legierungen
Influence des matériaux métalliques sur l'eau destinée à la consommation humaine -
Méthode d'évaluation du comportement passif des aciers inoxydables et autres alliages
passifs
Ta slovenski standard je istoveten z: EN 16056:2023
ICS:
13.060.20 Pitna voda Drinking water
67.250 Materiali in predmeti v stiku z Materials and articles in
živili contact with foodstuffs
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 16056
EUROPEAN STANDARD
NORME EUROPÉENNE
May 2023
EUROPÄISCHE NORM
ICS 67.250 Supersedes EN 16056:2012
English Version
Influence of metallic materials on water intended for
human consumption - Method to evaluate the passive
behaviour of stainless steels and other passive alloys
Influence des matériaux métalliques sur l'eau destinée Einfluss metallischer Werkstoffe auf Wasser für den
à la consommation humaine - Méthode d'évaluation du menschlichen Gebrauch - Verfahren zur Ermittlung des
comportement passif des aciers inoxydables et autres Passivverhaltens von nichtrostenden Stählen und
alliages passifs anderen Legierungen
This European Standard was approved by CEN on 24 April 2023.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2023 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 16056:2023 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
Introduction . 4
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Test cell . 5
5 Test water . 6
6 Sample preparation . 6
7 Test procedure . 6
8 Evaluation of test results . 7
9 Report . 7
Annex A (normative) Test cell and presentation of test results . 9

European foreword
This document (EN 16056:2023) has been prepared by Technical Committee CEN/TC 164 “Water
supply”, the secretariat of which is held by AFNOR.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by November 2023, and conflicting national standards
shall be withdrawn at the latest by November 2023.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN 16056:2012.
— scope extension with alloys with a passive behaviour comparable to stainless steel;
— other sample geometries than sheets have been added.
This document is one of a series of test methods which support associated product standards.
Any feedback and questions on this document should be directed to the users’ national standards body.
A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organisations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and the
United Kingdom.
Introduction
The test methods in this series are designed to provide information on metal release over time from
metallic materials into drinking water.
When tested in a test rig as described in EN 15664-1:2008+A1:2013, stainless steels show very low
metal release rates and the resulting metal concentrations in the water are in most cases below the
detection limits of available analytical instruments. The reason for these small metal release rates is the
formation of a passive layer on the surface on stainless steels.
It was therefore decided to test stainless steels for the properties of the passive layer and not metal
release. The material under consideration is tested in an electrochemical test. For verification of the
correct performance of the test protocol, the test is also performed in parallel on material 1.4404 which
is passive in contact with drinking water but shows a clear pitting potential under the conditions of this
test.
The test method is also applicable to alloys having a passive behaviour comparable to that of stainless
steels.
This test is terminated when the pitting potential of the material or the break-through potential is
reached.
With respect to the potential adverse effects on the quality of water intended for human consumption
caused by metallic materials, attention is drawn to the fact that the relevant national regulations remain
in force until the adoption of verifiable European acceptance criteria. Water intended for human
consumption is hereafter referred to as “drinking water” and means the same as the definition given in
Article 2(1) of the Council Directive 98/83/EC on the quality of water intended for human consumption.
This document describes the method to evaluate the passive behaviour of stainless steels and other
alloys in contact with water. The passive layer is the cause for the negligible release of metal ions from
stainless steels and other alloys into the drinking water.

1 Scope
This document specifies a procedure to evaluate the passive behaviour of stainless steels and other
passive alloys used in products intended to come into contact with drinking water.
The passive state is the reason why no r
...