CEN/TS 14495:2003

Leather - Chemical tests - Determination of chromium VI content

Migrated from Progress Sheet (TC Comment) (2000-07-10): WIs 054 and 055 are the result of the splitting of WI 006 (TC Res 5/1996) revised draft BP: Request for change of track, ENQ.+ Vote instead of UAP (TA/990 ++ 517) - BP approved --> track changed (Res BT C 147/1999) (CC/990812)++ CEN/TC 289 Res 5/2001: changed into ENV ++ CEN/TC 289 does not have any objection to change the ENVs into CEN/TS (CC/011008)

Leder - Chemische Prüfungen - Bestimmung des Chrom-VI-Gehaltes

Diese Technische Spezifikation legt ein Verfahren zur Bestimmung des Chrom(VI)-Gehaltes in Lösungen fest, die aus Leder unter festgelegten Bedingungen extrahiert wurden.

Cuir - Essais chimiques - Détermination de la teneur en chrome VI

Cette Spécification technique spécifie une méthode de détermination de la teneur en chrome VI de solutions obtenues par lessivage du cuir dans des conditions définies.

Usnje – Kemični preskusi – Določevanje kroma VI

General Information

• Status: Withdrawn
• Publication Date: 25-Mar-2003
• Withdrawal Date: 14-Nov-2007
• ICS: 59.140.30 - Leather and furs
• Technical Committee: CEN/TC 289 - Leather
• Drafting Committee: CEN/TC 289/WG 2 - Physical test methods
• Current Stage: 9960 - Withdrawal effective - Withdrawal
• Start Date: 15-Nov-2007
• Completion Date: 15-Nov-2007
• Ref Project: SIST-TS CEN/TS 14495:2004 - Leather - Chemical tests - Determination of chromium VI content

Relations

• Replaced By: EN ISO 17075:2007 - Leather - Chemical tests - Determination of chromium(VI) content (ISO 17075:2007)
• Effective Date: 22-Dec-2008

Standards Content (Sample)

SLOVENSKI STANDARD
SIST-TS CEN/TS 14495:2004
01-maj-2004
8VQMH±.HPLþQLSUHVNXVL±'RORþHYDQMHNURPD9,
Leather - Chemical tests - Determination of chromium VI content
Leder - Chemische Prüfungen - Bestimmung des Chrom-VI-Gehaltes
Cuir - Essais chimiques - Détermination de la teneur en chrome VI
Ta slovenski standard je istoveten z: CEN/TS 14495:2003
ICS:
59.140.30
SIST-TS CEN/TS 14495:2004 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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TECHNICAL SPECIFICATION
CEN/TS 14495
SPÉCIFICATION TECHNIQUE
TECHNISCHE SPEZIFIKATION
March 2003
ICS 59.140.30
English version
Leather – Chemical tests – Determination of chromium VI
content
This Technical Specification (CEN/TS) was approved by CEN on 27 October 2002 for provisional application.
The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to submit their
comments, particularly on the question whether the CEN/TS can be converted into a European Standard.
CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS available. It
is permissible to keep conflicting national standards in force (in parallel to the CEN/TS) until the final decision about the possible
conversion of the CEN/TS into an EN is reached.
CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece,
Hungary, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Slovakia, Spain, Sweden, Switzerland and United
Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2003 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TS 14495:2003 E
worldwide for CEN national Members.

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CEN/TS 14495:2003 (E)
Contents
Foreword.3
1 Scope .4
2 Normative references .4
3 Principle.4
4 Definitions.4
5 Chemicals .4
6 Apparatus .5
7 Procedure .6
8 Calculation and expression of results.8
9 Accuracy.9
10 Test report .9
Annex A (informative) Reversed Phase material.10
2

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CEN/TS 14495:2003 (E)
Foreword
This document (CEN/TS 14495:2003) has been prepared by Technical Committee CEN/TC 289 "Leather", the
secretariat of which is held by UNI.
The method described is suitable to quantify the chromium VI content in leathers down to 10 mg/kg and is suitable
to show whether a leather complies with the criteria "maximum 10 mg/kg" as it is given e.g. by the European
Commission decision of 17 February 1999 for the ecological criteria for the eco-label of leather for footwear.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to anounce this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal,
Slovakia, Spain, Sweden, Switzerland and the United Kingdom.
Annex A is informative.
3

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CEN/TS 14495:2003 (E)
1 Scope
This European Technical Specification specifies a method for determining chromium VI in solutions leached from
leather under defined conditions.
2 Normative references
This Technical Specification incorporates by dated or undated reference, provisions from other publications. These
normative references are cited at the appropriate places in the text and the publications are listed hereafter. For
dated references, subsequent amendments to or revisions of any of these publications apply to this Technical
Specification only when incorporated in it by amendment or revision. For undated references the latest edition of
the publication referred to applies (including amendments).
prEN 14676, Leather - Chemical tests - Determination of volatile matter
EN ISO 3696:1995, Water for analytical laboratory use - Specification and test methods (ISO 3696:1987)
EN ISO 4044, Leather - Preparation of chemical test samples (ISO 4044:1998)
EN ISO 2418:, Leather - Chemical, physical and mechanical and fastness tests - Sampling location (ISO
2418:2002)
EN ISO 2419, Leather – Physical and mechanical tests – Sample preparation and conditioning (ISO 2419:2002)
3 Principle
Soluble chromium VI is leached from the sample at pH 7,5 to 8,0 and substances which influence the detection are
removed by solid phase extraction if necessary. The chromium VI in solution oxidises 1,5-diphenylcarbazide to 1,5-
diphenylcarbazone to give a red/violet complex with chromium which can be quantified photometrically at 540 nm.
The results obtained from the described method are strictly dependant on the extraction conditions. Results
obtained by using other extraction procedures (extraction solution, pH, extraction time, etc.) are not comparable
with the results produced by the procedure described in this Technical Specification.
4 Definitions
For the purposes of this Technical Specification the following applies:
chromium VI content is the amount of chromium VI in leather determined by this method after extraction with an
aqueous salt solution at pH 7,5-8,0. Chromium VI content is reported as chromium VI in mg/kg. In cases where wet
leathers, e.g. wet blues, are analysed, the content is given in mg/kg based on dry matter (prEN 14676)
5 Chemicals
All reagents used shall have at least analytical grade purity.
5.1 Extraction solution:
22,8 g dipotassiumhydrogenphosphate K HPO . 3H O dissolved in 1 000 ml water, adjusted to pH 8,0 – 0,1 with
2 4 2
phosphoric acid (5.3). This solution shall be degassed with either argon or nitrogen
4

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CEN/TS 14495:2003 (E)
5.2 Diphenylcarbazide solution:
1,0 g 1,5-diphenylcarbazide CO(NHNHC H ) is dissolved in 100 ml acetone (CH ) CO and made acidic with one
6 5 2 3 2
drop of glacial acetic acid CH COOH.
3
The solution should be kept in a brown glass bottle. The shelf life is up to 14 days at 4 °C.
5.3 Phosphoric acid solution:
700 ml o-phosphoric acid d = 1,71 g/ml, made up to 1 000 ml with distilled water.
5.4 Chromium VI stock solution:
2,829 g potassium dichromate (K Cr O ) (5.8), is dissolved into water in a volumetric flask and made up to 1 000 ml
2 2 7
with water. 1 ml of this solution contains 1 mg of chromium.
5.5 Chromium VI standard solution:
1 ml of solution (5.4), is pipetted into a 1 000 ml volumetric flask and made up to the mark with distilled water. 1 ml
of this solution contains 1 μg of chromium.
5.6 Argon or nitrogen, oxygen free
5.7 Distilled water of Grade 3 (EN ISO 3696:1995)
5.8 Potassium dichromate (K Cr O ), dried for 16 h – 2 h at 102 °C – 2 °C
2 2 7
5.9 Methanol
6 Apparatus
-1 -1
6.1 Suitable mechanical shaker, 50 revmin to 150 revmin
6.2 Conical flask, 250 ml, with stopper
6.3 Aeration tube and flow meter
6.4 pH meter with glass electrode
6.5 Membrane filter, 0,45 μm pore size (Teflon or Nylon)
6.6 Volumetric flasks, 25 ml, 100 ml, 1000 ml
6.7 Pipettes, nominal volumes 0,5/1,0/2,0/5,0/10/20/25 ml
6.8 Spectrophotometer or filterphotometer, wavelength 540 nm
6.9 Photometric cell, quartz, 2 cm path length or any other suitable cell path length
6.10 Glass or polypropylene cartridges filled with suitable reversed phase materials, e.g. RP 18
6.11 SPE-system (Solid Phase Extraction) with vacuum device or solvent resistant medical syringe.
5

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