EN ISO 9224:2012

Corrosion of metals and alloys - Corrosivity of atmospheres - Guiding values for the corrosivity categories (ISO 9224:2012)

ISO 9224:2012 specifies guiding values of corrosion attack for metals and alloys exposed to natural outdoor atmospheres for exposures greater than one year. It is intended to be used in conjunction with ISO 9223.
Guiding corrosion values for standard structural materials can be used for engineering calculations. The guiding corrosion values specify the technical content of each of the individual corrosivity categories for these standard metals.
ISO 9224:2012 provides examples of calculated maximum corrosion attack after extended exposure (up to 20 years) for six standardized corrosivity categories.
It provides presumed average initial and steady-state corrosion rates of standard metals in intervals relative to six standardized corrosivity categories.
It provides the calculation procedure for corrosion attack of steels in regard to their composition.

Korrosion von Metallen und Legierungen - Korrosivität von Atmosphären - Anhaltswerte für die Korrosivitätskategorien (ISO 9224:2012)

Diese Internationale Norm legt Anhaltswerte für den Korrosionsangriff bei Metallen und Legierungen fest, die
in natürlichen Atmosphären im Außenbereich für mehr als ein Jahr ausgelagert werden. Diese Internationale
Norm ist dazu gedacht, in Verbindung mit ISO 9223 angewendet zu werden.
Anhaltswerte für die Korrosion von genormten Konstruktionswerkstoffen können für bautechnische
Berechnungen verwendet werden. Die Anhaltswerte für die Korrosion legen den technischen Inhalt jeder der
einzelnen Korrosivitätskategorien für diese metallischen Standardproben fest.
In Anhang A sind Beispiele für einen berechneten maximalen Korrosionsangriff nach einer längeren
Auslagerung (bis zu 20 Jahre) für sechs genormte Korrosivitätskategorien angeführt.
In Anhang B sind die Intervalle von mittleren anfänglichen und mittleren stabilen Korrosionsgeschwindigkeiten
bezogen auf die sechs in ISO 9223 festgelegten Korrosivitätskategorien von metallischen Standardprobe
angeführt.
In Anhang C ist das Berechnungsverfahren für den Korrosionsangriffs bei Stählen in Bezug auf deren
Zusammensetzung angeführt.

Corrosion des métaux et alliages - Corrosivité des atmosphères - Valeurs de référence relatives aux classes de corrosivité (ISO 9224:2012)

L'ISO 9224:2012 spécifie des valeurs de référence d'attaque par corrosion pour des métaux et des alliages exposés à des atmosphères naturelles extérieures pendant des périodes supérieures à un an. Elle est destinée à être utilisée conjointement avec l'ISO 9223.
Les valeurs de référence de corrosion relatives à des matériaux de construction de référence peuvent être utilisées lors de calculs de conception. Les valeurs de référence de corrosion spécifient le contenu technique de chaque classe de corrosivité individuelle applicable à ces métaux de référence.
L'ISO 9224:2012 fournit des exemples d'attaque par corrosion maximale calculée après une exposition prolongée (jusqu'à 20 ans) pour six classes de corrosivité normalisées.
Elle indique les valeurs supposées des vitesses moyennes initiales et stabilisées de corrosion des métaux de référence dans les intervalles relatifs à six classes de corrosivité normalisées.
Elle décrit la méthode de calcul de l'attaque par corrosion des aciers en fonction de leur composition.

Korozija kovin in zlitin - Korozivnost v atmosferskem okolju - Vodilne vrednosti za kategorizacijo korozivnosti (ISO 9224:2012)

Ta mednarodni standard določa vodilne vrednosti napada korozije za kovine in zlitine, ki so izpostavljene naravnim zunanjim atmosferam dlje od enega leta. Ta mednarodni standard je treba uporabljati v povezavi s standardom ISO 9223. Vodilne korozijske vrednosti za standardne konstrukcijske materiale je mogoče uporabiti za inženirske izračune. Vodilne korozijske vrednosti določajo tehnično vsebino vsake posamezne kategorije korozivnosti za te standardne kovine. Dodatek A prikazuje primere izračunanega najobsežnejšega napada korozije po daljši izpostavljenosti (do 20 let) za šest standardiziranih kategorij korozivnosti. Dodatek B prikazuje predpostavljene povprečne prvotne in ustaljene hitrosti korozije standardnih kovin v intervalih glede na šest standardiziranih kategorij korozivnosti. Dodatek C prikazuje postopek za izračun napada korozije na jekla glede na njihovo sestavo.

General Information

• Status: Published
• Publication Date: 31-Jan-2012
• Withdrawal Date: 30-Aug-2012
• ICS: 77.060 - Corrosion of metals
• Technical Committee: CEN/TC 262 - Metallic and other inorganic coatings
• Drafting Committee: CEN/TC 262 - Metallic and other inorganic coatings
• Current Stage: 6060 - Definitive text made available (DAV) - Publishing
• Start Date: 01-Feb-2012
• Completion Date: 01-Feb-2012
• Ref Project: SIST EN ISO 9224:2012 - Corrosion of metals and alloys - Corrosivity of atmospheres - Guiding values for the corrosivity categories (ISO 9224:2012)

Relations

• Replaces: EN 12500:2000 - Protection of metallic materials against corrosion - Corrosion likelihood in atmospheric environment - Classification, determination and estimation of corrosivity of atmospheric environments
• Effective Date: 08-Jun-2022

Standards Content (Sample)

SLOVENSKI STANDARD
01-maj-2012
1DGRPHãþD
SIST EN 12500:2000
Korozija kovin in zlitin - Korozivnost v atmosferskem okolju - Vodilne vrednosti za
kategorizacijo korozivnosti (ISO 9224:2012)
Corrosion of metals and alloys - Corrosivity of atmospheres - Guiding values for the
corrosivity categories (ISO 9224:2012)
Korrosion von Metallen und Legierungen - Korrosivität von Atmosphären - Anhaltswerte
für die Korrosivitätskategorien (ISO 9224:2012)
Corrosion des métaux et alliages - Corrosivité des atmosphères - Valeurs de référence
relatives aux classes de corrosivité (ISO 9224:2012)
Ta slovenski standard je istoveten z: EN ISO 9224:2012
ICS:
77.060 Korozija kovin Corrosion of metals
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN ISO 9224
NORME EUROPÉENNE
EUROPÄISCHE NORM
February 2012
ICS 77.060 Supersedes EN 12500:2000
English Version
Corrosion of metals and alloys - Corrosivity of atmospheres -
Guiding values for the corrosivity categories (ISO 9224:2012)
Corrosion des métaux et alliages - Corrosivité des Korrosion von Metallen und Legierungen - Korrosivität von
atmosphères - Valeurs de référence relatives aux classes Atmospären - Anhaltswerte für die Korrosivitätskategorien
de corrosivité (ISO 9224:2012) (ISO 9224:2012)
This European Standard was approved by CEN on 22 January 2012.

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, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2012 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 9224:2012: E
worldwide for CEN national Members.

Contents Page
Foreword .3

Foreword
This document (EN ISO 9224:2012) has been prepared by Technical Committee ISO/TC 156 "Corrosion of
metals and alloys" in collaboration with Technical Committee CEN/TC 262 “Metallic and other inorganic
coatings” the secretariat of which is held by BSI.
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 2012, and conflicting national standards shall be withdrawn at
the latest by August 2012.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN 12500:2000.
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, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland, Turkey and the United Kingdom.
Endorsement notice
The text of ISO 9224:2012 has been approved by CEN as a EN ISO 9224:2012 without any modification.

INTERNATIONAL ISO
STANDARD 9224
Second edition
2012-02-01
Corrosion of metals and alloys —
Corrosivity of atmospheres — Guiding
values for the corrosivity categories
Corrosion des métaux et alliages — Corrosivité des atmosphères —
Valeurs de référence relatives aux classes de corrosivité

Reference number
ISO 9224:2012(E)
©
ISO 2012
ISO 9224:2012(E)
©  ISO 2012
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or
ISO's member body in the country of the requester.
ISO copyright office
Case postale 56  CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail [e-mail]
Web www.iso.org
Published in Switzerland
ii © ISO 2012 – All rights reserved

ISO 9224:2012(E)
Contents Page
Foreword . iv
Introduction . v
1  Scope . 1
2  Normative references . 1
3  Terms and definitions . 1
4  Principle . 2
5  Prediction of corrosion attack after extended exposure . 2
6  Specific criteria for calculation of corrosion rates of structural metals . 3
6.1  Steels . 3
6.2  Zinc materials . 4
6.3  Copper alloys . 4
6.4  Aluminium alloys . 4
7  Long-term exposures . 4
Annex A (informative) Example of maximum corrosion attack after extended exposures for
corrosivity categories . 7
Annex B (informative) Average initial corrosion rates and average steady corrosion rates in
intervals relative to classified corrosivity categories . 9
Annex C (informative) Prediction of corrosion attack of steels with regard to steel composition . 10
Bibliography . 12

ISO 9224:2012(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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
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.
ISO 9224 was prepared by Technical Committee ISO/TC 156, Corrosion of metals and alloys.
This second edition cancels and replaces the first edition (ISO 9224:1992), which has been technically revised.
iv © ISO 2012 – All rights reserved

ISO 9224:2012(E)
Introduction
The “corrosivity category” established in ISO 9223 is a general term suitable for engineering purposes, which
describes the corrosion properties of atmospheres based on current knowledge of atmospheric corrosion.
Guiding values of corrosion attack can be used to predict the extent of corrosion attack in long-term exposures
based on measurements of corrosion attack in the first-year exposure to the outdoor atmosphere in question.
These values can also be used to determine conservative estimates of corrosion attack based on
environmental information or corrosivity category estimates as shown in ISO 9223.
Corrosion attack estimates obtained by using the methods in this International Standard can be used to
predict the useful life of metallic components and, in some cases, of metallic coatings exposed to outdoor
atmospheres covered by ISO 9223. The corrosion attack results can also be used to determine whether or not
protective measures, such as coatings, are required to achieve desired product lives. Other uses include the
selection of construction materials for outdoor atmospheric service.
Guiding values of corrosion can be used as information for the selection of a protection method against
atmospheric corrosion according to ISO 11303.
The guiding values in this International Standard are based on a large number of exposures in many locations
throughout the world. However, the procedure used in this International Standard cannot possibly cover all the
situations in natural environments and service conditions which can occur. In particular, situations that result
in significant changes in the environment can cause major increases or decreases in corrosion rates. Users of
this International Standard are cautioned to consult with qualified experts in the field of outdoor atmospheric
corrosion in cases where localized corrosion can be more important than general attack. The specific issues
of galvanic (bi-metallic) corrosion, pitting corrosion, crevice corrosion, environmental cracking and corrosion
product wedging are not addressed in this International Standard.

INTERNATIONAL STANDARD ISO 9224:2012(E)

Corrosion of metals and alloys — Corrosivity of atmospheres —
Guiding values for the corrosivity categories
1 Scope
This International Standard specifies guiding values of corrosion attack for metals and alloys exposed to
natural outdoor atmospheres for exposures greater than one year. This International Standard is intended to
be used in conjunction with ISO 9223.
Guiding corrosion values for standard structural materials can be used for engineering calculations. The
guiding corrosion values specify the technical content of each of the individual corrosivity categories for these
standard metals.
Annex A provides examples of calculated maximum corrosion attack after extended exposure (up to 20 years)
for six standardized corrosivity categories.
Annex B provides presumed average initial and steady-state corrosion rates of standard metals in intervals
relative to six standardized corrosivity categories.
Annex C provides the calculation procedure for corrosion attack of steels in regard to their composition.
2 Normative references
The following referenced documents are indispensable for the application 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 8044, Corrosion of metals and alloys — Basic terms and definitions
ISO 9223, Corrosion of metals and alloys — Corrosivity of atmospheres — Classification, determination and
estimation
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 8044 and the following apply.
3.1
guiding corrosion value
corrosion rates, mass loss, penetration or other corrosion characteristics expressing the expected corrosive
action of the atmospheric environment of a given corrosivity category towards standard metals
3.2
corrosion rate after extended exposure
corrosion rate after exposures longer than one year
...