SIST EN ISO 19396-1:2025

Paints and varnishes - Determination of pH value - Part 1: pH sensors with glass membrane (ISO 19396-1:2025)

This document specifies a method for laboratory measurement of the pH value of polymer dispersions and coating materials using pH sensors with a glass membrane.

Beschichtungsstoffe - Bestimmung des pH-Wertes - Teil 1: pH-Sensoren mit Glasmembran (ISO 19396-1:2025)

Dieses Dokument legt ein Verfahren zum Messen des pH Wertes von Polymerdispersionen und Beschichtungsstoffen mit pH Sensoren mit Glasmembran im Labor fest.

Peintures et vernis - Détermination de la valeur de pH - Partie 1: Sondes de pH à membrane en verre (ISO 19396-1:2025)

Le présent document spécifie une méthode de mesure en laboratoire de la valeur de pH des dispersions de polymères et des produits de peinture à l’aide de sondes de pH à membrane en verre.

Barve in laki - Določanje pH-vrednosti - 1. del: pH-sonde s stekleno membrano (ISO 19396-1:2025)

Ta dokument določa metodo za laboratorijsko merjenje pH-vrednosti polimernih disperzij in premaznih materialov z uporabo pH-sond s stekleno membrano.

General Information

• Status: Published
• Public Enquiry End Date: 19-Sep-2024
• Publication Date: 19-Aug-2025
• ICS: 87.040 - Paints and varnishes
• Technical Committee: IBLP - Paints and varnishes
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 24-Jul-2025
• Due Date: 28-Sep-2025
• Completion Date: 20-Aug-2025
• Ref Project: EN ISO 19396-1:2025 - Paints and varnishes - Determination of pH value - Part 1: pH sensors with glass membrane (ISO 19396-1:2025)

Relations

• Replaces: SIST EN ISO 19396-1:2020 - Paints and varnishes - Determination of pH value - Part 1: pH electrodes with glass membrane (ISO 19396-1:2017)
• Effective Date: 01-Sep-2025

Overview

EN ISO 19396-1:2025 - "Paints and varnishes - Determination of pH value - Part 1: pH sensors with glass membrane" (ISO 19396-1:2025) is a CEN-adopted laboratory method for measuring the pH value of polymer dispersions and coating materials using glass membrane pH sensors. Published July 2025 and replacing earlier editions, this standard clarifies terminology (changing “pH electrode” to pH sensor), calibration requirements and normative references to support consistent, traceable pH measurement across paints and varnishes testing laboratories.

Key topics

• Scope and principle: Specifies laboratory measurement principles for aqueous coating systems and polymer dispersions using potentiometric pH measuring chains with a glass membrane.
• Apparatus and materials: Details required equipment such as pH measuring apparatus, pH meter, glass-membrane pH sensors, temperature sensors, buffer solutions and storage solutions for sensors.
• Sampling and sample preparation: References ISO sampling and sample preparation protocols to ensure representative, reproducible results.
• Calibration and procedure: Defines calibration steps using buffer solutions, test conditions, number of determinations and stepwise measurement procedures for robust pH determination.
• Evaluation and reporting: Covers data evaluation, required contents of the test report, and handling of measurement stability.
• Precision: Presents precision information including repeatability (r) and reproducibility (R) limits derived from interlaboratory studies.
• Informative annexes: Annex A recommends pH sensors for different coating groups; Annex B explains determination of precision.

Applications

EN ISO 19396-1:2025 is intended for:

• Quality control laboratories in paint and varnish manufacturing for formulation control and batch release.
• R&D teams assessing formulation stability, shelf life and compatibility of polymer dispersions and coating systems.
• External testing laboratories providing accredited pH measurement services.
• Regulatory and conformity assessment activities where documented, standardized pH measurement is required.

Practical benefits include improved comparability of pH data, better sensor selection guidance, and clearer calibration practices for glass membrane pH measurement in coatings.

Related standards

• ISO 19396-2 (pH measurement using ISFET sensors) - complementary method for non-glass sensors.
• ISO 1513, ISO 4618, ISO 15528, ISO 80000-9 - normative references for sampling, vocabulary and units used in this standard.

Keywords: EN ISO 19396-1:2025, paints and varnishes, pH measurement, glass membrane pH sensor, polymer dispersions, coating materials, laboratory method, pH value determination.

Standards Content (Sample)

SLOVENSKI STANDARD
01-september-2025
Nadomešča:
SIST EN ISO 19396-1:2020
Barve in laki - Določanje pH-vrednosti - 1. del: pH-sonde s stekleno membrano
(ISO 19396-1:2025)
Paints and varnishes - Determination of pH value - Part 1: pH sensors with glass
membrane (ISO 19396-1:2025)
Beschichtungsstoffe - Bestimmung des pH-Wertes - Teil 1: pH-Sensoren mit
Glasmembran (ISO 19396-1:2025)
Peintures et vernis - Détermination de la valeur de pH - Partie 1: Sondes de pH à
membrane en verre (ISO 19396-1:2025)
Ta slovenski standard je istoveten z: EN ISO 19396-1:2025
ICS:
87.040 Barve in laki Paints and varnishes
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 19396-1
EUROPEAN STANDARD
NORME EUROPÉENNE
July 2025
EUROPÄISCHE NORM
ICS 87.040 Supersedes EN ISO 19396-1:2020
English Version
Paints and varnishes - Determination of pH value - Part 1:
pH sensors with glass membrane (ISO 19396-1:2025)
Peintures et vernis - Détermination de la valeur de pH - Beschichtungsstoffe - Bestimmung des pH-Wertes -
Partie 1: Sondes de pH à membrane en verre (ISO Teil 1: pH-Sensoren mit Glasmembran (ISO 19396-
19396-1:2025) 1:2025)
This European Standard was approved by CEN on 27 June 2025.

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
© 2025 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 19396-1:2025 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 19396-1:2025) has been prepared by Technical Committee ISO/TC 35 "Paints
and varnishes" in collaboration with Technical Committee CEN/TC 139 “Paints and varnishes” the
secretariat of which is held by DIN.
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 January 2026, and conflicting national standards shall
be withdrawn at the latest by January 2026.
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 ISO 19396-1:2020.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organizations 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.
Endorsement notice
The text of ISO 19396-1:2025 has been approved by CEN as EN ISO 19396-1:2025 without any
modification.
International
Standard
ISO 19396-1
Second edition
Paints and varnishes —
2025-06
Determination of pH value —
Part 1:
pH sensors with glass membrane
Peintures et vernis — Détermination de la valeur de pH —
Partie 1: Sondes de pH à membrane en verre
Reference number
ISO 19396-1:2025(en) © ISO 2025

ISO 19396-1:2025(en)
© ISO 2025
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii
ISO 19396-1:2025(en)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 4
5 Apparatus and materials . 4
5.1 pH measuring apparatus .4
5.2 pH meter .5
5.3 pH sensor .5
5.4 Buffer solutions .7
5.5 Storage solution for the pH sensors .7
6 Sampling . 7
7 Procedure . 7
7.1 Test conditions .7
7.2 Calibration .7
7.3 Number of determinations .8
7.4 Measuring the pH value .8
8 Evaluation . 8
9 Precision . 8
9.1 General .8
9.2 Repeatability limit, r . .8
9.3 Reproducibility limit, R .9
10 Test report . 9
Annex A (informative) Recommended pH sensors for different groups of coating materials,
based on the results of interlaboratory tests. 10
Annex B (informative) Determination of precision .12
Bibliography . 14

iii
ISO 19396-1:2025(en)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee
has been established has the right to be represented on that committee. International organizations,
governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely
with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO document should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 35, Paints and varnishes, Subcommittee
SC 9, General test methods for paints and varnishes, in collaboration with the European Committee for
Standardization (CEN) Technical Committee CEN/TC 139, Paints and varnishes, in accordance with the
Agreement on technical cooperation between ISO and CEN (Vienna Agreement).
This second edition cancels and replaces the first edition (ISO 19396-1:2017), which has been technically
revised.
The main changes are as follows:
— definitions for “theoretical slope”, “stability of measured value”, “potentiometric measurement chain”
and “reference element” have been deleted;
— the term “pH electrode” has been changed to “pH sensor” in the entire text including the title of the
document;
— the calibration (7.2) has been clarified;
— the normative references have been updated.
A list of all parts in the ISO 19396 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.

iv
ISO 19396-1:2025(en)
Introduction
The pH value of aqueous products is of decisive importance for the product properties and durability.
This document covers a method for laboratory measurement of the pH value of polymer dispersions and
coating materials using pH sensors with a glass membrane. ISO 19396-2 specifies a method for measuring
the pH value using pH sensors with ion-sensitive field-effect transistor (ISFET) technology.

v
International Standard ISO 19396-1:2025(en)
Paints and varnishes — Determination of pH value —
Part 1:
pH sensors with glass membrane
1 Scope
This document specifies a method for laboratory measurement of the pH value of polymer dispersions and
coating materials using pH sensors with a glass membrane.
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 1513, Paints and varnishes — Examination and preparation of test samples
ISO 4618, Paints and varnishes — Vocabulary
ISO 15528, Paints, varnishes and raw materials for paints and varnishes — Sampling
ISO 80000-9, Quantities and units — Part 9: Physical chemistry and molecular physics
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 4618, ISO 80000-9 and the
following apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
pH
measure for the acidic or basic reaction of an aqueous solution or polymer dispersion
Note 1 to entry: For the notation of pH, the p and the H are vertically on one line. The same is valid for pOH.
Note 2 to entry: The acidic reaction is determined by the activity of the existing “hydrogen ions”. The basic reaction
is determined by the activity of the existing hydroxide ions. The direct relationship between the activities of the
“hydrogen ions” and the hydroxide ions is described by the ionic product of the water.
3.2
pH value
decadal logarithm of the hydrogen ion activity multiplied with (−1)
a m ⋅γ
   
++ +
HH H
pH==p a −lg =−lg
   
+
H  00  
m m
   
ISO 19396-1:2025(en)
with am=⋅γ
++ +
H H H
where
a
is the activity of the hydrogen ion, in mol/kg;
+
H
is the standard molality (1 mol/kg);
m
γ
is the activity coefficient of the hydrogen ion;
+
H
m
is the molality of the hydrogen ion, in mol/kg.
+
H
Note 1 to entry: For further details see DIN 19261.
3.3
pH sensor
pH electrode
pH combination electrode
pH measuring chain
pH single-rod measuring chain
potentiometric measuring chain providing a voltage which depends on the pH value (3.2) of the
measuring medium
Note 1 to entry: The two electrochemical half cells are the pH measuring electrode and the reference ele
...