EN ISO 17226-2:2019

Leather - Chemical determination of formaldehyde content - Part 2: Method using colorimetric analysis (ISO 17226-2:2018)

This document specifies a method for the determination of free and released formaldehyde in leathers. This method, based on colorimetric analysis, is not intended to be used for a precise quantification of formaldehyde.
The formaldehyde content is taken to be the quantity of free-formaldehyde and formaldehyde extracted through hydrolysis contained in a water extract from the leather under standard conditions.
This process is not absolutely selective for formaldehyde. Other compounds such as extracted dyes could interfere at 412 nm.

Leder - Chemische Bestimmung des Formaldehydgehalts - Teil 2: Verfahren mittels kolorimetrischer Analyse (ISO 17226-2:2018)

Cuir - Dosage chimique du formaldéhyde - Partie 2: Méthode par analyse colorimétrique (ISO 17226-2:2018)

Le présent document spécifie une méthode permettant de doser le formaldéhyde libre et le formaldéhyde dégagé dans les cuirs. Cette méthode, fondée sur l'analyse colorimétrique, n'est pas destinée à obtenir une quantification précise du formaldéhyde.
La teneur en formaldéhyde est définie comme étant la quantité de formaldéhyde libre et de formaldéhyde extrait par hydrolyse contenue dans un extrait d'eau provenant du cuir dans des conditions normalisées.
Ce processus n'est pas absolument sélectif pour le formaldéhyde. D'autres composants, tels que des extraits de teintures, pourraient interférer à 412 nm.

Usnje - Kemijsko določevanje formaldehida - 2. del: Analiza s kolorimetrijsko metodo (ISO 17226-2:2018)

Ta dokument določa metodo za ugotavljanje prostega in sproščenega formaldehida v usnju.
Ta metoda, ki temelji na kolorimetrijski analizi, ni namenjena temu, da bi se uporabljala za natančno kvantifikacijo formaldehida.
Za vsebnost formaldehida se šteje količina prostega formaldehida in formaldehida, izvlečenega s hidrolizo v vodnem izvlečku iz usnja pod standardnimi pogoji. Ta postopek ni absolutno selektiven za formaldehid. Druge spojine, na primer izvlečene barve, lahko povzročajo interferenco pri 412 nm.

General Information

• Status: Published
• Publication Date: 05-Feb-2019
• Withdrawal Date: 30-Aug-2019
• ICS: 59.140.30 - Leather and furs
• Technical Committee: CEN/TC 289 - Leather
• Drafting Committee: CEN/TC 289/WG 1 - Chemical test methods
• Current Stage: 6060 - Definitive text made available (DAV) - Publishing
• Start Date: 06-Feb-2019
• Completion Date: 06-Feb-2019
• Ref Project: SIST EN ISO 17226-2:2019 - Leather - Chemical determination of formaldehyde content - Part 2: Method using colorimetric analysis (ISO 17226-2:2018)

Relations

• Replaces: EN ISO 17226-2:2008/AC:2009 - Leather - Chemical determination of formaldehyde content - Part 2: Method using colorimetric analysis (ISO 17226-2:2008/Cor 1:2009)
• Effective Date: 13-Feb-2019
• Replaces: EN ISO 17226-2:2008 - Leather - Chemical determination of formaldehyde content - Part 2: Method using colorimetric analysis (ISO 17226-2:2008)
• Effective Date: 10-May-2017

Overview

EN ISO 17226-2:2019 - "Leather - Chemical determination of formaldehyde content - Part 2: Method using colorimetric analysis" (adopted by CEN) specifies a screening colorimetric method for determining free and released formaldehyde in leather. The method reports the formaldehyde content present in a water extract obtained under standard conditions. It is intended for routine screening rather than for highly precise quantification.

Key topics and requirements

• Scope: Measurement of free-formaldehyde plus formaldehyde released by hydrolysis in a water extract from leather. Not fully selective for formaldehyde; other extracted compounds (e.g., dyes) can interfere at the analytical wavelength.
• Principle: Leather is eluted with a detergent solution at 40 °C. Formaldehyde in the eluate reacts with acetylacetone to form a yellow derivative (3,5-diacetyl-1,4-dihydrolutidine) whose absorbance is measured at 412 nm. Results are obtained from a calibration curve prepared under identical conditions.
• Reagents and apparatus: Uses common analytical-grade reagents (e.g., detergent solution, ammonium acetate/acetylacetone mix, dimedone for checks) and standard lab equipment, including a spectrophotometer capable of readings at 412 nm and a thermostatically controlled water bath at (40 ± 1) °C.
• Limitations: The method is not absolutely selective for formaldehyde; co-extracted substances can produce a colour at 412 nm. For disputes or when precise quantification is required, ISO 17226-1 (HPLC method) is the preferred reference.
• Quality control: The standard includes calibration, blank checks for reagents, spiking and recovery checks, and guidance on sampling and sample preparation.

Applications and users

• Practical use: Fast screening of leather batches for formaldehyde content during production, incoming material inspection, or routine quality control.
• Who uses it:
  • Leather manufacturers and tanneries performing in-house QC
  • Independent testing laboratories offering formaldehyde screening
  • Regulatory bodies and compliance officers checking product safety limits
  • Product designers and procurement teams verifying supplier claims
• Why choose this method: Colorimetric analysis is relatively simple, cost-effective and faster than chromatographic techniques, making it suitable for routine screening where approximate trends are acceptable.

Related standards

• ISO 17226-1 - Leather - Chemical determination of formaldehyde content - Part 1: Method using high performance liquid chromatography (HPLC) (for precise quantification)
• Normative references incorporated in EN ISO 17226-2: ISO 2418, ISO 3696, ISO 4044, ISO 4684 (sampling, water quality, sample prep and volatile matter)

Keywords: EN ISO 17226-2:2019, formaldehyde determination, leather testing, colorimetric analysis, acetylacetone, 412 nm, screening method, ISO 17226 series.

Standards Content (Sample)

SLOVENSKI STANDARD
01-april-2019
1DGRPHãþD
SIST EN ISO 17226-2:2009
SIST EN ISO 17226-2:2009/AC:2009
8VQMH.HPLMVNRGRORþHYDQMHIRUPDOGHKLGDGHO$QDOL]DVNRORULPHWULMVNR
PHWRGR,62
Leather - Chemical determination of formaldehyde content - Part 2: Method using
colorimetric analysis (ISO 17226-2:2018)
Leder - Chemische Bestimmung des Formaldehydgehalts - Teil 2: Verfahren mittels
kolorimetrischer Analyse (ISO 17226-2:2018)
Cuir - Dosage chimique du formaldéhyde - Partie 2: Méthode par analyse colorimétrique
(ISO 17226-2:2018)
Ta slovenski standard je istoveten z: EN ISO 17226-2:2019
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 17226-2
EUROPEAN STANDARD
NORME EUROPÉENNE
February 2019
EUROPÄISCHE NORM
ICS 59.140.30 Supersedes EN ISO 17226-2:2008
English Version
Leather - Chemical determination of formaldehyde content
- Part 2: Method using colorimetric analysis (ISO 17226-
2:2018)
Cuir - Dosage chimique du formaldéhyde - Partie 2: Leder - Chemische Bestimmung des
Méthode par analyse colorimétrique (ISO 17226- Formaldehydgehalts - Teil 2: Verfahren mittels
2:2018) kolorimetrischer Analyse (ISO 17226-2:2018)
This European Standard was approved by CEN on 16 December 2018.

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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, 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
© 2019 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 17226-2:2019 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 17226-2:2019) 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 August 2019, and conflicting national standards shall
be withdrawn at the latest by August 2019.
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 17226-2:2008.
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, Former Yugoslav Republic of Macedonia,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,
Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
Endorsement notice
The text of ISO 17226-2:2018 has been approved by CEN as EN ISO 17226-2:2019 without any
modification.
INTERNATIONAL ISO
STANDARD 17226-2
IULTCS/IUC 19-2
Second edition
2018-12
Leather — Chemical determination of
formaldehyde content —
Part 2:
Method using colorimetric analysis
Cuir — Dosage chimique du formaldéhyde —
Partie 2: Méthode par analyse colorimétrique
Reference numbers
ISO 17226-2:2018(E)
IULTCS/IUC 19-2:2018(E)
©
ISO 2018
ISO 17226-2:2018(E)
IULTCS/IUC 19-2:2018(E)
© ISO 2018
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]
Fax: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii © ISO 2018 – All rights reserved

ISO 17226-2:2018(E)
IULTCS/IUC 19-2:2018(E)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Conformance . 1
5 Principle . 2
6 Reagents . 2
6.1 Reagents for the formaldehyde stock solution . 2
6.2 Reagents for the colorimetric method . 2
7 Apparatus . 2
8 Procedures . 3
8.1 Procedure for the determination of formaldehyde in the stock solution . 3
8.1.1 Preparation of the formaldehyde stock solution . . 3
8.1.2 Determination . 3
8.2 Procedure for the determination of formaldehyde in leather by the colorimetric method . 4
8.2.1 Sampling and preparation of samples . 4
8.2.2 Extraction . 4
8.2.3 Reaction with acetylacetone . 4
8.2.4 Checking reagents for absence of formaldehyde . 4
8.2.5 Testing other compounds which cause a colouring with acetylacetone . 4
8.2.6 Calibration . 5
8.2.7 Calculation of the content of formaldehyde of the leather sample. 5
8.2.8 Spiking and recovery rate . 5
9 Expression of results . 6
10 Test report . 6
Annex A (informative) Precision: reliability of the colorimetric method . 8
ISO 17226-2:2018(E)
IULTCS/IUC 19-2:2018(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 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 the European Committee for Standardization (CEN) Technical
Committee CEN/TC 289, Leather, in collaboration with the Chemical Test Commission of the
International Union of Leather Technologists and Chemists Societies (IUC Commission, IULTCS), in
accordance with the Agreement on technical cooperation between ISO and CEN (Vienna Agreement).
This method is technically similar to the Colorimetric Section of the method IUC 19, which was declared
an official method at the IULTCS Delegates meeting on 31st May 2003 in Cancún, Mexico.
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 sampling and the testing of leather. ISO
recognizes IULTCS as an international standardizing body for the preparation of test methods for
leather.
This second edition cancels and replaces the first edition (ISO 17226-2:2008), which has been
technically revised. It also incorporates the Technical Corrigendum ISO 17226-2:2008/Cor.1:2009. The
main changes compared to the previous edition are as follows:
— Clause 1 has been modified;
— the former Clause 2 has become Clause 4, a new Clause 3, Terms and definitions, inserted and
subsequent clauses renumbered;
— 6.1.1, 6.2.1, 6.2.2, 7.4, 7.7, 8.2.2, 8.2.3, 8.2.4, 8.2.6 and 8.2.8 have been technically modified.
A list of all parts in the ISO 17226 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 2018 – All rights reserved

ISO 17226-2:2018(E)
INTERNATIONAL STANDARD
IULTCS/IUC 19-2:2018(E)
Leather — Chemical determination of formaldehyde
content —
Part 2:
Method using colorimetric analysis
1 Scope
This document specifies a method for the determination of free and released formaldehyde in leathers.
This method, based on colorimetric analysis, is not intended to be used for a precise quantification of
formaldehyde.
The formaldehyde content is taken to be the quantity of free-formaldehyde and formaldehyde extracted
through hydrolysis contained in a water extract from the leather under standard conditions.
This process is not absolutely selective for formaldehyde. Other compounds such as extracted dyes
could interfere at 412 nm.
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 lates
...