EN ISO 20137:2023

SLOVENSKI STANDARD
01-februar-2024
Usnje - Kemijski preskusi - Smernice za preskušanje kritičnih kemikalij v usnju
(ISO 20137:2023)
Leather - Chemical tests - Guidelines for testing critical chemicals in leather (ISO
20137:2023)
Leder - Chemische Prüfverfahren - Richtlinien für die Prüfung kritischer Chemikalien in
Leder (ISO 20137:2023)
Cuir - Essais chimiques - Lignes directrices pour les essais de produits chimiques
critiques sur le cuir (ISO 20137:2023)
Ta slovenski standard je istoveten z: EN ISO 20137:2023
ICS:
59.140.30 Usnje in krzno Leather and furs
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 20137
EUROPEAN STANDARD
NORME EUROPÉENNE
November 2023
EUROPÄISCHE NORM
ICS 59.140.30 Supersedes EN ISO 20137:2017
English Version
Leather - Chemical tests - Guidelines for testing critical
chemicals in leather (ISO 20137:2023)
Cuir - Essais chimiques - Lignes directrices pour les Leder - Chemische Prüfverfahren - Richtlinien für die
essais de produits chimiques critiques sur le cuir (ISO Prüfung kritischer Chemikalien in Leder (ISO
20137:2023) 20137:2023)
This European Standard was approved by CEN on 19 November 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 ISO 20137:2023 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 20137:2023) has been prepared by Technical Committee ISO/IULTCS
"International Union of Leather Technologists and Chemists Societies " in collaboration with Technical
Committee CEN/TC 289 “Leather” the secretariat of which is held by UNI.
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 May 2024, and conflicting national standards shall be
withdrawn at the latest by May 2024.
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 20137:2017.
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 20137:2023 has been approved by CEN as EN ISO 20137:2023 without any modification.

INTERNATIONAL ISO
STANDARD 20137
IULTCS
IUC 36
Second edition
2023-11
Leather — Chemical tests —
Guidelines for testing critical
chemicals in leather
Cuir — Essais chimiques — Lignes directrices pour les essais de
produits chimiques critiques sur le cuir
Reference numbers
ISO 20137:2023(E)
IULTCS/IUC 36:2023(E)
ISO 20137:2023(E)
IULTCS/IUC 36:2023(E)
© ISO 2023
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: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
ISO 20137:2023(E)
IULTCS/IUC 36:2023(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Chemical substances potentially found in leather . 1
4.1 Chemical test methods for substances used by the leather industry with no
current legal restrictions for leather . 1
4.2 Chemical test methods for substances previously used by the leather industry . 3
4.3 Chemical test methods for substances not conventionally or intentionally used by
the leather industry . 6
Annex A (informative) Substance lists . 8
Bibliography .13
iii
ISO 20137:2023(E)
IULTCS/IUC 36:2023(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 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.
IULTCS, originally formed in 1897, is a world-wide organization of professional leather societies to
further the advancement of leather science and technology. IULTCS has three Commissions, which
are responsible for establishing international methods for the sampling and testing of leather. ISO
recognizes IULTCS as an international standardizing body for the preparation of test methods for
leather.
This document was prepared by the Chemical Tests Commission of the International Union of Leather
Technologists and Chemists Societies (IUC Commission, IULTCS), in collaboration with the European
Committee for Standardization (CEN) Technical Committee CEN/TC 289, Leather, in accordance with
the Agreement on technical cooperation between ISO and CEN (Vienna Agreement).
This second edition cancels and replaces the first edition (ISO 20137:2017), which has been technically
revised.
The main changes are as follows:
— testing standards updated;
— new substances added in Table 1 (bisphenols, glutaraldehyde);
— new substance added in Table 3 (brominated flame retardants);
— new Tables A.3 and A.5 added to Annex A.
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 20137:2023(E)
IULTCS/IUC 36:2023(E)
Introduction
0.1  General
This document is intended to provide an overview of chemical test methods for the leather industry.
It can be used by those involved in setting specifications for leather, especially for those parameters
relating to restricted chemical substances.
Regulations restrict the use of certain chemicals in consumer products. The leather industry has already
taken action by replacing restricted substances or assuming the limits imposed by these restrictions.
Many brand-name manufacturers require certificates of compliance from their suppliers but too often
these refer to analytical methods from other industries that are not suitable for use in testing leather.
Through the collaboration of IULTCS and CEN/TC 289, a considerable number of leather-specific
International and European standard test methods have been developed for the chemical analysis
of leather. The International Standards are tested by interlaboratory studies, have been proven
scientifically valid and are subjected to updating processes according to ISO protocols.
0.2  Chemical analysis of leather
Leather is a complex substrate to chemically analyse. After tanning, leather typically undergoes wet-
processing in aqueous media at low temperatures (<60 °C) and in an acid pH range of 3,5 to 5,5. The
characteristic properties of leather are achieved by mostly using a range of anionic retanning agents
(natural and/or synthetic), polymers and oils, as well as anionic dyes for achieving the required colour.
In analytical procedures, when leather is extracted, some of these substances can be removed and make
a complex matrix for the analysis. This should be considered when establishing quantification limits
for leather analyses. Too often, unrealistic limits established in aqueous solutions, for example waste
water analysis, are quoted in specifications for leather.
This document gives an overview of those internationally accepted chemical test methods established
specifically for leather.
v
ISO 20137:2023(E)
INTERNATIONAL STANDARD
IULTCS/IUC 36:2023(E)
Leather — Chemical tests — Guidelines for testing critical
chemicals in leather
1 Scope
This document provides lists of chemicals that have already been detected in leather and guidelines
for applying the available chemical test methods for leather. This information can be used by thos
...