EN ISO 19396-1:2020

SLOVENSKI STANDARD
01-april-2020
Barve in laki - Določevanje pH-vrednosti - 1. del: pH-elektrode s stekleno
membrano (ISO 19396-1:2017)
Paints and varnishes - Determination of pH value - Part 1: pH electrodes with glass
membrane (ISO 19396-1:2017)
Beschichtungsstoffe - Bestimmung des pH-Wertes - Teil 1: pH-Elektroden mit
Glasmembran (ISO 19396-1:2017)
Peintures et vernis - Détermination de la valeur pH - Partie 1: Électrodes pH avec
membrane de verre (ISO 19396-1:2017)
Ta slovenski standard je istoveten z: EN ISO 19396-1:2020
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
February 2020
EUROPÄISCHE NORM
ICS 87.040
English Version
Paints and varnishes - Determination of pH value - Part 1:
pH electrodes with glass membrane (ISO 19396-1:2017)
Peintures et vernis - Détermination de la valeur pH - Beschichtungsstoffe - Bestimmung des pH-Wertes -
Partie 1: Électrodes pH avec membrane de verre (ISO Teil 1: pH-Elektroden mit Glasmembran (ISO 19396-
19396-1:2017) 1:2017)
This European Standard was approved by CEN on 4 November 2019.

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, Turkey 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
© 2020 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 19396-1:2020 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
The text of ISO 19396-1:2017 has been prepared by Technical Committee ISO/TC 35 "Paints and
varnishes” of the International Organization for Standardization (ISO) and has been taken over as
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 August 2020, and conflicting national standards shall
be withdrawn at the latest by August 2020.
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.
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, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO 19396-1:2017 has been approved by CEN as EN ISO 19396-1:2020 without any
modification.
INTERNATIONAL ISO
STANDARD 19396-1
First edition
2017-08
Paints and varnishes — Determination
of pH value —
Part 1:
pH electrodes with glass membrane
Peintures et vernis — Détermination de la valeur pH —
Partie 1: Électrodes pH avec membrane de verre
Reference number
ISO 19396-1:2017(E)
©
ISO 2017
ISO 19396-1:2017(E)
© ISO 2017, Published in Switzerland
All rights reserved. Unless otherwise specified, 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
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Tel. +41 22 749 01 11
Fax +41 22 749 09 47
copyright@iso.org
www.iso.org
ii © ISO 2017 – All rights reserved

ISO 19396-1:2017(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 5
5 Apparatus and materials. 5
6 Sampling . 8
7 Procedure. 8
7.1 Test conditions . 8
7.2 Calibration . 8
7.3 Number of determinations . 9
7.4 Measuring the pH value . 9
8 Evaluation . 9
9 Precision . 9
9.1 General . 9
9.2 Repeatability limit, r  . 9
9.3 Reproducibility limit, R  .10
10 Test report .10
Annex A (informative) Recommended pH electrodes for different groups of coating
materials, based on the results of interlaboratory tests .11
Annex B (informative) Determination of precision .13
Bibliography .15
ISO 19396-1:2017(E)
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 documents 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).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on 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 the following
URL: w w w . i s o .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.
A list of all parts in the ISO 19396 series can be found on the ISO website.
iv © ISO 2017 – All rights reserved

ISO 19396-1:2017(E)
Introduction
The pH value of aqueous products is of decisive importance for the product properties and durability.
INTERNATIONAL STANDARD ISO 19396-1:2017(E)
Paints and varnishes — Determination of pH value —
Part 1:
pH electrodes 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 electrodes with a glass membrane. ISO 19396-2 specifies a method
for measuring the pH value using pH electrodes with ion-sensitive field-effect transistor (ISFET)
technology.
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 — Terms and definitions
ISO 15528, Paints, varnishes and raw materials for paints and varnishes — Sampling
ISO 80000-9:2009, Quantities and units — Part 9: Physical chemistry and molecular physics
3 Terms and definitions
For the purpose of this document, the terms and definitions given in ISO 4618 and ISO 80000-9 and the
following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http:// www .electropedia .org/
— ISO Online browsing platform: available at http:// www .iso .org/ obp
3.1
pH
measure for the acidic or basic reaction of an aqueous solution or polymer dispersion
Note 1 to entry: 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)
m ⋅γ 
a  ++
+
HHm,
H
 
pH==p a −lg  =−lg
+
H 00


 
m m
 
 
ISO 19396-1:2017(E)
with am=⋅γ
++ +
HH m,H
where
is the activity of the hydrogen ion, in mol/kg;
a
+
H
0 is the standard molality (1 mol/kg);
m
is the activity coefficient of the hydrogen ion;
γ
+
m,H
is the molality of the hydrogen ion, in mol/kg.
m
+
H
Note 1 to entry: The pH value is not measurable as a measure of a single ion activity. Therefore, pH (PS) values of
solutions of primary reference material (PS, en: Primary Standard) are determined, which are approximate to it
and can be attributed to it. This is based on a worldwide agreement; see ISO 80000-9:2009, Annex C.
3.3
potentiometric measuring chain
combination of electrochemical half cells
3.4
pH (combination) electrode
pH (single-rod) measuring chain
potentiometric measuring chain (3.3) providing a voltage which depends on the pH value (3.2) of the
measuring solution
Note 1 to entry: One of the two electrochemical half cells is the pH measuring electrode, the second is a reference
electrode (3.5) (see Figure 1). Both electrodes can be combined as a single-rod measuring chain in one unit.
Note 2 to entry: An integrated temperature sensor is recommended (see Figure 1).
2 © ISO 2017 – All rights reserved

ISO 19396-1:2017(E)
Key
1 reference electrode, consisting of 2, 3 and 4 6 reference element
2 reference element 7 glass membrane
3 reference electrolyte 8 internal buffer
4 diaphragm 9 temperature sensor
5 pH measuring electrode, consisting of 6, 7 and 8 U pH proportional voltage
Figure 1 — Design of a pH electrode with glass membrane and temperature sensor
(schematic illustration)
Note 3 to entry: This document refers to pH electrodes with glass membrane. The electrode shaft should be made
of material resistant to chemicals and solvents.
3.5
reference electrode
electrode providing a constant potential which is independent from the pH value (3.2) of the
measuring medium
Note 1 to entry: At present, the most commonly used type is the silver/silver chloride reference electrode, whose
potential is stabilized by a constant concentration of potassium chloride (KCl) in the reference electrolyte (3.7).
3.6
reference element
galvanic cell which dips into the reference electrolyte (3.7) and transmits the reference potential to the
pH meter
Note 1 to entry: The reference elements of the pH measuring electrode and of the reference electrode should be
aligned so that identical temperature characteristics are given.
ISO 19396-1:2017(E)
3.7
reference electrolyte
aque
...