SIST EN ISO 9556:2025

SLOVENSKI STANDARD
01-september-2025
Jeklo in železo - Določanje skupne vsebnosti ogljika - Infrardeča absorpcijska
metoda po zgorevanju v indukcijski peči (ISO 9556:2025)
Steel and iron - Determination of total carbon content - Infrared absorption method after
combustion in an induction furnace (ISO 9556:2025)
Stahl und Eisen - Bestimmung des Gesamtkohlenstoffgehalts - Verfahren mit
Infrarotabsorption nach Verbrennung im Induktionsofen (ISO 9556:2025)
Aciers et fontes - Détermination du carbone total - Méthode par absorption dans
l'infrarouge après combustion dans un four à induction (ISO 9556:2025)
Ta slovenski standard je istoveten z: EN ISO 9556:2025
ICS:
77.040.30 Kemijska analiza kovin Chemical analysis of metals
77.080.01 Železne kovine na splošno Ferrous metals in general
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 9556
EUROPEAN STANDARD
NORME EUROPÉENNE
July 2025
EUROPÄISCHE NORM
ICS 77.080.01 Supersedes EN ISO 9556:2001
English Version
Steel and iron - Determination of total carbon content -
Infrared absorption method after combustion in an
induction furnace (ISO 9556:2025)
Aciers et fontes - Détermination du carbone total -  Stahl und Eisen - Bestimmung des
Méthode par absorption dans l'infrarouge après Gesamtkohlenstoffgehalts - Verfahren mit
combustion dans un four à induction (ISO 9556:2025) Infrarotabsorption nach Verbrennung im
Induktionsofen (ISO 9556:2025)
This European Standard was approved by CEN on 14 July 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 9556:2025 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 9556:2025) has been prepared by Technical Committee ISO/TC 17 "Steel" in
collaboration with Technical Committee CEN/TC 459/SC 2 “Methods of chemical analysis for iron and
steel ” the secretariat of which is held by SIS.
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 9556:2001.
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 9556:2025 has been approved by CEN as EN ISO 9556:2025 without any modification.

International
Standard
ISO 9556
Second edition
Steel and iron — Determination
2025-07
of total carbon content —
Infrared absorption method after
combustion in an induction furnace
Aciers et fontes — Détermination du carbone total — Méthode
par absorption dans l'infrarouge après combustion dans un four
à induction
Reference number
ISO 9556:2025(en) © ISO 2025
ISO 9556:2025(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
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Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
ISO 9556:2025(en)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 1
5 Reagents . 1
6 Apparatus . 2
7 Sampling and sample preparation . 3
8 Procedure . 3
8.1 General operating instructions .3
8.2 Test portion .3
8.3 Blank test .4
8.4 Determination .4
8.5 Establishment of the calibration curve .4
8.5.1 Samples having carbon contents between 0,003 % (mass fraction) and 0,01 %
(mass fraction) .4
8.5.2 Samples having carbon contents between 0,01 % (mass fraction) and 0,1 %
(mass fraction) .5
8.5.3 Samples having carbon contents between 0,1 % (mass fraction) and 1,0 %
(mass fraction) .6
8.5.4 Samples having carbon contents between 1,0 % (mass fraction) and 4,5 %
(mass fraction) .6
9 Expression of results . 7
9.1 Method of calculation .7
9.2 Precision . . .7
10 Test report . 8
Annex A (informative) Additional information on the international precision tests. 9
Annex B (informative) Graphical representation of precision data .11
Annex C (informative) Features of commercial high-frequency induction furnaces and infrared
carbon analysers . . .12
Bibliography . 14

iii
ISO 9556:2025(en)
Foreword
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This document was prepared by Technical Committee ISO/TC 17, Steel, Subcommittee SC 1, Methods of
determination of chemical compositi
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