EN ISO 12944-5:2007
(Main)Paints and varnishes - Corrosion protection of steel structures by protective paint systems - Part 5: Protective paint systems (ISO 12944-5:2007)
Paints and varnishes - Corrosion protection of steel structures by protective paint systems - Part 5: Protective paint systems (ISO 12944-5:2007)
ISO 12944-5:2007 describes the types of paint and paint system commonly used for corrosion protection of steel structures. It also provides guidance for the selection of paint systems available for different environments and different surface preparation grades, and the durability grade to be expected. The durability of paint systems is classified in terms of low, medium and high.
Beschichtungsstoffe - Korrosionsschutz von Stahlbauten durch Beschichtungssysteme - Teil 5: Beschichtungssysteme (ISO 12944-5:2007)
Dieser Teil von ISO 12944 beschreibt die für den Korrosionsschutz von Stahlbauten allgemein verwendeten Typen von Beschichtungsstoffen und Beschichtungssystemen. Er gibt auch Hinweise für die Auswahl von Beschichtungssystemen, die für verschiedene Umgebungsbedingungen (siehe ISO 12944 2) zur Verfügung stehen, zu verschiedenen Oberflächenvorbereitungsgraden (siehe ISO 12944 4), und zu der zu erwartenden Schutzdauer (siehe ISO 12944 1). Die Schutzdauer von Beschichtungssystemen wird in niedrig, mittel und hoch eingeteilt.
Peintures et vernis - Anticorrosion des structures en acier par systèmes de peinture - Partie 5: Systèmes de peinture (ISO 12944-5:2007)
L'ISO 12944-5:2007 décrit les types de peinture et de systèmes de peinture couramment utilisés pour la protection contre la corrosion des structures en acier. Elle fournit également des directives pour le choix de systèmes de peinture adaptés aux différents environnements, qualités de préparation de surface et niveau de durabilité attendu. La durabilité des systèmes de peinture est classée en termes de durabilité limitée, moyenne et élevée.
Barve in laki - Korozijska zaščita jeklenih konstrukcij z zaščitnimi premaznimi sistemi - 5. del: Zaščitni premazni sistemi (ISO 12944-5:2007)
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
01-januar-2009
1DGRPHãþD
SIST EN ISO 12944-5:1998
%DUYHLQODNL.RUR]LMVND]DãþLWDMHNOHQLKNRQVWUXNFLM]]DãþLWQLPLSUHPD]QLPL
VLVWHPLGHO =DãþLWQLSUHPD]QLVLVWHPL ,62
Paints and varnishes - Corrosion protection of steel structures by protective paint
systems - Part 5: Protective paint systems (ISO 12944-5:2007)
Beschichtungsstoffe - Korrosionsschutz von Stahlbauten durch Beschichtungssysteme -
Teil 5: Beschichtungssysteme (ISO 12944-5:2007)
Peintures et vernis - Anticorrosion des structures en acier par systemes de peinture -
Partie 5: Systemes de peinture (ISO 12944-5:2007)
Ta slovenski standard je istoveten z: EN ISO 12944-5:2007
ICS:
25.220.20 Površinska obdelava Surface treatment
87.040 Barve in laki Paints and varnishes
91.080.13 Jeklene konstrukcije Steel structures
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EUROPEAN STANDARD
EN ISO 12944-5
NORME EUROPÉENNE
EUROPÄISCHE NORM
September 2007
ICS 87.020 Supersedes EN ISO 12944-5:1998
English Version
Paints and varnishes - Corrosion protection of steel structures
by protective paint systems - Part 5: Protective paint systems
(ISO 12944-5:2007)
Peintures et vernis - Anticorrosion des structures en acier Beschichtungsstoffe - Korrosionsschutz von Stahlbauten
par systèmes de peinture - Partie 5: Systèmes de peinture durch Beschichtungssysteme - Teil 5:
(ISO 12944-5:2007) Beschichtungssysteme (ISO 12944-5:2007)
This European Standard was approved by CEN on 24 June 2007.
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 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 Management Centre has the same status as the
official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, 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 and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36 B-1050 Brussels
© 2007 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 12944-5:2007: E
worldwide for CEN national Members.
Contents Page
Foreword.3
Foreword
This document (EN ISO 12944-5:2007) has been prepared by Technical Committee ISO/TC 35 "Paints and
varnishes" in collaboration with Technical Committee CEN/TC 139 "Paints and varnishes", the secretariat of
which is held by DIN.
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 March 2008, and conflicting national standards shall be withdrawn at
the latest by March 2008.
This document supersedes EN ISO 12944-5:1998.
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, 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 and the United Kingdom.
Endorsement notice
The text of ISO 12944-5:2007 has been approved by CEN as a EN ISO 12944-5:2007 without any
modification.
INTERNATIONAL ISO
STANDARD 12944-5
Second edition
2007-09-15
Paints and varnishes — Corrosion
protection of steel structures by
protective paint systems —
Part 5:
Protective paint systems
Peintures et vernis — Anticorrosion des structures en acier par
systèmes de peinture —
Partie 5: Systèmes de peinture
Reference number
ISO 12944-5:2007(E)
©
ISO 2007
ISO 12944-5:2007(E)
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ii © ISO 2007 – All rights reserved
ISO 12944-5:2007(E)
Contents Page
Foreword. iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions. 2
4 Types of paint. 4
4.1 General. 4
4.2 Reversible coatings. 4
4.3 Irreversible coatings. 4
4.4 General properties of different generic types of paint. 7
5 Paint systems. 7
5.1 Classification of environments and surfaces to be painted . 7
5.2 Type of primer . 8
5.3 Low-VOC paint systems. 9
5.4 Dry film thickness. 9
5.5 Durability . 9
5.6 Shop and site application . 10
6 Tables for protective paint systems . 11
6.1 Reading the tables. 11
6.2 Parameters influencing durability. 11
6.3 Designation of the paint systems listed. 12
6.4 Guidelines for selecting the appropriate paint system. 12
Annex A (informative) Paint systems . 13
Annex B (informative) Pre-fabrication primers . 23
Annex C (informative) General properties . 25
Annex D (informative) Volatile organic compounds (VOCs). 26
Bibliography . 28
ISO 12944-5:2007(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 12944-5 was prepared by Technical Committee ISO/TC 35, Paints and varnishes, Subcommittee SC 14,
Protective paint systems for steel structures.
This second edition cancels and replaces the first edition (ISO 12944-5:1998), which has been technically
revised. The revision includes a reduction in the number of paint systems and in the number of tables. These
changes have also brought about some changes in the numbering of the systems in the tables.
ISO 12944 consists of the following parts, under the general title Paints and varnishes — Corrosion protection
of steel structures by protective paint systems:
⎯ Part 1: General introduction
⎯ Part 2: Classification of environments
⎯ Part 3: Design considerations
⎯ Part 4: Types of surface and surface preparation
⎯ Part 5: Protective paint systems
⎯ Part 6: Laboratory performance test methods and associated assessment criteria
⎯ Part 7: Execution and supervision of paint work
⎯ Part 8: Development of specifications for new work and maintenance
iv © ISO 2007 – All rights reserved
ISO 12944-5:2007(E)
Introduction
Unprotected steel in the atmosphere, in water and in soil is subjected to corrosion that may lead to damage.
Therefore, to avoid corrosion damage, steel structures are normally protected to withstand the corrosion
stresses during the required service life of the structure.
There are different ways of protecting steel structures from corrosion. ISO 12944 deals with protection by
paint systems and covers, in the various parts, all features that are important in achieving adequate corrosion
protection. Other measures are possible, but require particular agreement between the interested parties.
In order to ensure effective corrosion protection of steel structures, it is necessary for owners of such
structures, planners, consultants, companies carrying out corrosion protection work, inspectors of protective
coatings and manufacturers of coating materials to have at their disposal state-of-the-art information in
concise form on corrosion protection by paint systems. Such information has to be as complete as possible,
unambiguous and easily understandable to avoid difficulties and misunderstandings between the parties
concerned with the practical implementation of protection work.
This International Standard — ISO 12944 — is intended to give this information in the form of a series of
instructions. It is written for those who have some technical knowledge. It is also assumed that the user of
ISO 12944 is familiar with other relevant International Standards, in particular those dealing with surface
preparation, as well as relevant national regulations.
Although ISO 12944 does not deal with financial and contractual questions, attention is drawn to the fact that,
because of the considerable implications of inadequate corrosion protection, non-compliance with
requirements and recommendations given in this standard might result in serious financial consequences.
ISO 12944-1 defines the overall scope of all parts of ISO 12944. It gives some basic terms and definitions and
a general introduction to the other parts of ISO 12944. Furthermore, it includes a general statement on health,
safety and environmental protection, and guidelines for using ISO 12944 for a given project.
ISO 12944-5 gives some terms and definitions related to paint systems in combination with guidance for the
selection of different types of protective paint system.
INTERNATIONAL STANDARD ISO 12944-5:2007(E)
Paints and varnishes — Corrosion protection of steel structures
by protective paint systems —
Part 5:
Protective paint systems
1 Scope
This part of ISO 12944 describes the types of paint and paint system commonly used for corrosion protection
of steel structures. It also provides guidance for the selection of paint systems available for different
environments (see ISO 12944-2) and different surface preparation grades (see ISO 12944-4), and the
durability grade to be expected (see ISO 12944-1). The durability of paint systems is classified in terms of low,
medium and high.
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 2808, Paints and varnishes — Determination of film thickness
ISO 3549, Zinc dust pigments for paints — Specifications and test methods
ISO 4628-1, Paints and varnishes — Evaluation of degradation of coatings — Designation of quantity and size
of defects, and of intensity of uniform changes in appearance — Part 1: General introduction and designation
system
ISO 4628-2, Paints and varnishes — Evaluation of degradation of coatings — Designation of quantity and size
of defects, and of intensity of uniform changes in appearance — Part 2: Assessment of degree of blistering
ISO 4628-3, Paints and varnishes — Evaluation of degradation of coatings — Designation of quantity and size
of defects, and of intensity of uniform changes in appearance — Part 3: Assessment of degree of rusting
ISO 4628-4, Paints and varnishes — Evaluation of degradation of coatings — Designation of quantity and size
of defects, and of intensity of uniform changes in appearance — Part 4: Assessment of degree of cracking
ISO 4628-5, Paints and varnishes — Evaluation of degradation of coatings — Designation of quantity and size
of defects, and of intensity of uniform changes in appearance — Part 5: Assessment of degree of flaking
ISO 4628-6, Paints and varnishes — Evaluation of degradation of coatings — Designation of quantity and size
of defects, and of intensity of uniform changes in appearance — Part 6: Assessment of degree of chalking by
tape method
ISO 8501-1, Preparation of steel substrates before application of paints and related products — Visual
assessment of surface cleanliness — Part 1: Rust grades and preparation grades of uncoated steel
substrates and of steel substrates after overall removal of previous coatings
ISO 12944-5:2007(E)
ISO 8501-3, Preparation of steel substrates before application of paints and related products — Visual
assessment of surface cleanliness — Part 3: Preparation grades of welds, edges and other areas with surface
imperfections
ISO 12944-1, Paints and varnishes — Corrosion protection of steel structures by protective paint systems —
Part 1: General introduction
ISO 12944-2, Paints and varnishes — Corrosion protection of steel structures by protective paint systems —
Part 2: Classification of environments
ISO 12944-4:1998, Paints and varnishes — Corrosion protection of steel structures by protective paint
systems — Part 4: Types of surface and surface preparation
ISO 12944-6, Paints and varnishes — Corrosion protection of steel structures by protective paint systems —
Part 6: Laboratory performance test methods and associated assessment criteria
ISO 19840, Paints and varnishes — Corrosion protection of steel structures by protective paint systems —
Measurement of, and acceptance criteria for, the thickness of dry films on rough surfaces
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 12944-1 and the following terms
and definitions apply.
3.1
high-build
property of a coating material which permits the application of a coat of greater thickness than usually
considered as normal for that type of coating
NOTE For the purposes of this part of ISO 12944, this means W 80 µm dry film thickness per coat.
3.2
high-solids
property of a coating material which contains a volume of solids greater than normal for that coating material
3.3
compatibility
〈for products within a paint system〉 ability of two or more products to be used together successfully as a paint
system without causing undesirable effects
3.4
compatibility
〈between a product and the substrate〉 ability of a product to be applied to a substrate without causing
undesirable effects
3.5
priming coat
first coat of a coating system
NOTE Priming coats provide good adhesion to sufficiently roughened, cleaned metal and/or cleaned old coating,
ensuring a sound base for, and offering adhesion to, the subsequent coats. They normally also provide corrosion
protection during the overcoating interval and the whole service life of the paint system.
3.6
intermediate coat
any coat between the priming coat and the finishing coat/topcoat
NOTE In the English language, the term “undercoat” is sometimes used synonymously, normally for a coat applied
directly before the finishing coat/topcoat.
2 © ISO 2007 – All rights reserved
ISO 12944-5:2007(E)
3.7
topcoat
final coat of a coating system
3.8
tie coat
coat designed to improve intercoat adhesion and/or avoid certain defects during application
3.9
stripe coat
supplementary coat applied to ensure uniform coverage of critical and difficult to coat areas such as edges,
welds, etc.
3.10
dry film thickness
DFT
thickness of a coating remaining on the surface when the coating has hardened/cured
3.11
nominal dry film thickness
NDFT
dry film thickness specified for each coat or for the whole paint system
3.12
maximum dry film thickness
highest acceptable dry film thickness above which the performance of the paint or the paint system could be
impaired
3.13
primer
paint that has been formulated for use as a priming coat on prepared surfaces
3.14
pre-fabrication primer
fast-drying paint that is applied to blast-cleaned steel to provide temporary protection during fabrication while
still allowing welding and cutting
NOTE In many languages, the term pre-fabrication primer does not have the same meaning as in English.
3.15
pot life
maximum time, at any particular temperature, during which a coating material supplied as separate
components can successfully be used after they have been mixed together
3.16
shelf life
time during which a coating material will remain in good condition when stored in its original sealed container
under normal storage conditions
NOTE The expression “normal storage conditions” is usually understood to mean storage between +5 °C and +30 °C.
3.17
volatile organic compound
VOC
any organic liquid and/or solid that evaporates spontaneously at the prevailing temperature and pressure of
the atmosphere with which it is in contact
ISO 12944-5:2007(E)
4 Types of paint
4.1 General
For the protection of steel structures against corrosion many paint systems are widely used.
Based on the corrosivity category, various examples of anticorrosive paint systems are given, in relation to the
expected durability, in Tables A.1 to A.8 in Annex A, which is informative in nature. The systems have been
included because of their proven track record, but the list is NOT intended to be exhaustive and other similar
systems are also available.
In addition, new technologies are continually being developed, often driven by government legislation, and
these should always be considered where appropriate and where performance has been validated by:
a) the track record of such technologies and/or
b) the results of testing at least in accordance with ISO 12944-6.
NOTE 1 The information given in 4.2, 4.3 and 4.4 concerns only the chemical and physical properties of paints and not
the way they are used. The limits given for drying and curing temperatures are only indicative. Variations can be expected
for each type of paint, depending on its formulation.
For the purposes of application, paints can be classified as solvent-borne, water-borne or solvent-free. They
are first divided into two main categories according to the manner in which they dry and cure (see 4.2 and 4.3)
and then subdivided (see 4.3.2 to 4.3.5) by generic type and mechanism of cure.
NOTE 2 The main physical and mechanical properties are summarized in Annex C.
4.2 Reversible coatings
The film dries by solvent evaporation with no other change of form, i.e. the process is reversible and the film
can be re-dissolved in the original solvent at any time.
Examples of binders in this type of coating material are:
a) chlorinated rubber (CR);
b) vinyl chloride copolymers (also known as PVC);
c) acrylic polymers (AY).
The drying time will depend, among other things, on air movement and temperature. Drying can take place
down to 0 °C, although at low temperatures it is much slower.
4.3 Irreversible coatings
4.3.1 General considerations
The film dries initially by solvent evaporation (where a solvent is present) followed by a chemical reaction or
by coalescence (in some water-borne paints). The process is irreversible, meaning that the film cannot be
dissolved in the original solvent or, in the case of a solvent-free coating, in a solvent typically used with that
generic type of paint.
4 © ISO 2007 – All rights reserved
ISO 12944-5:2007(E)
4.3.2 Air-drying paints (oxidative curing)
In these paints, the film hardens/forms by evaporation of solvent, followed by reaction of the binder with
oxygen from the atmosphere.
Typical binders are:
⎯ alkyd;
⎯ urethane alkyd;
⎯ epoxy ester.
The drying time will depend, among other things, on the temperature. The reaction with oxygen can take place
down to 0 °C, although at low temperatures it is much slower.
4.3.3 Water-borne paints (single pack)
In this type of paint, the binder is dispersed in water. The film hardens by evaporation of water and
coalescence of the dispersed binder to form a film.
The process is irreversible, i.e. this type of coating is not re-dispersible in water after drying.
Binders which are typically dispersed in water are:
⎯ acrylic polymers (AY);
⎯ vinyl polymers (PVC);
⎯ polyurethane resins (PUR).
The drying time will depend, among other things, on air movement, relative humidity and temperature. Drying
can take place down to +3 °C, although at low temperatures it is much slower. High humidity (greater than
80 % RH) also impedes the drying process.
4.3.4 Chemically curing paints
4.3.4.1 General considerations
In general, this type of paint consists of a base component and a curing agent component. The mixture of
base and curing agent has a limited pot life (see 3.15).
The paint film dries by evaporation of solvents, if present, and cures by a chemical reaction between the base
and the curing agent components.
The types given below are commonly in use.
NOTE The base component and/or the curing agent component may be pigmented.
4.3.4.2 Epoxy 2-pack paints
4.3.4.2.1 Base component
The binders in the base component are polymers having epoxy groups, which react with suitable curing
agents.
ISO 12944-5:2007(E)
Typical binders are:
⎯ epoxy;
⎯ epoxy vinyl/epoxy acrylic;
⎯ epoxy combinations (e.g. epoxy hydrocarbon resins);
Formulations can be solvent-borne, water-borne or solvent-free.
Most epoxy coatings chalk when exposed to sunlight. If colour or gloss retention is required, the topcoat
should be an aliphatic polyurethane (see 4.3.4.3) or a suitable physically drying type (see 4.2) or water-borne
(see 4.3.3).
4.3.4.2.2 Curing agent component
Polyaminoamines (polyamines), polyaminoamides (polyamides) or adducts of these are most commonly used.
Polyamides are more suitable for primers because of their good wetting properties. Polyamine-cured coatings
are generally more resistant to chemicals.
The drying time will depend, amongst other things, on air movement and on the temperature. The curing
reaction can take place down to + 5 °C, and lower for specialist products.
4.3.4.3 Polyurethane 2-pack paints
4.3.4.3.1 Base component
The binders are polymers with free hydroxyl groups which react with suitable isocyanate curing agents.
Typical binders are:
⎯ polyester;
⎯ acrylic;
⎯ epoxy;
⎯ polyether;
⎯ fluoro resin;
⎯ polyurethane combinations (e.g. polyurethane hydrocarbon resins) (PURC).
4.3.4.3.2 Curing agent component
Aromatic or aliphatic polyisocyanates are most commonly used.
Aliphatic-polyisocyanate-cured products (PUR, aliphatic) have excellent gloss-retention and colour-retention
properties if combined with a suitable base component.
Aromatic-polyisocyanate-cured products (PUR, aromatic) give faster curing but are much less suitable for
exterior exposure because they tend to chalk and discolour more rapidly.
The drying time will depend, among other things, on air movement and temperature. The curing reaction can
take place down to 0 °C, or lower, but the relative humidity should be kept within the paint manufacturer's
recommended range to ensure coatings are free from bubbles and/or pinholes.
6 © ISO 2007 – All rights reserved
ISO 12944-5:2007(E)
4.3.5 Moisture-curing paints
The film dries/forms by solvent evaporation. It cures chemically by reacting with moisture from the air.
Typical binders are:
⎯ polyurethane (1-pack);
⎯ ethyl silicate (2-pack);
⎯ ethyl silicate (1-pack).
The drying time will depend, amongst other things, on the temperature, the air movement, the humidity and
the film thickness. The curing reaction can take place down to 0 °C, or lower, provided that the air still contains
sufficient moisture. The lower the relative humidity, the slower the curing.
It is important that the paint manufacturer's instructions regarding the limits for relative humidity and wet and
dry film thickness are complied with in order to avoid bubbles, pinholes or other defects in the coating.
4.4 General properties of different generic types of paint
Further information is given in Annex C. This annex is intended only as an aid to selection but, if it is used, it
should be used in combination with Tables A.1 to A.8 in Annex A, manufacturers’ published data and
experience gained from previous projects.
5 Paint systems
5.1 Classification of environments and surfaces to be painted
5.1.1 Classification of environments
In accordance with ISO 12944-2, the environment is divided into the following categories:
Six atmospheric corrosivity categories:
C1 very low;
C2 low;
C3 medium;
C4 high;
C5-I very high (industrial);
C5-M very high (marine).
Three categories for water and soil:
Im1 immersion in fresh water;
Im2 immersion in sea or brackish water;
Im3 buried in soil.
ISO 12944-5:2007(E)
5.1.2 Surfaces to be painted
5.1.2.1 New structures
The substrates encountered in new structures are low-alloy steel of rust grade A, B and C as defined in
ISO 8501-1, as well as galvanized steel and metallized steel (see ISO 12944-1). Possible preparation of the
different substrates is described in ISO 12944-4. The substrate and the recommended preparation grade are
given at the head of Tables A.1 to A.8 in this part of ISO 12944 for each corrosivity category. The paint
systems listed in Annex A are typical examples of systems used in the environments defined in ISO 12944-2
when applied to steel surfaces with rust grades A to C, as defined in ISO 8501-1, or to hot-dip-galvanized
steel or metallized steel. Where the steel has deteriorated to the extent that pitting corrosion has taken place
(rust grade D in ISO 8501-1), the dry film thickness or the number of coats shall be increased to compensate
for the increased surface roughness, and the paint manufacturer should be consulted for recommendations.
In principle, no corrosion protection is required for corrosivity category C1. If, for aesthetic reasons, painting is
necessary, a system intended for corrosivity category C2 (with a low durability) may be chosen.
If unprotected steelwork destined for corrosivity category C1 is initially transported, stored temporarily or
assembled in an exposed situation (for example, a C4/C5 coastal environment), corrosion will commence due
to air-borne contaminants/salts and will continue even when the steelwork is moved to its final category C1
location. To avoid this problem, the steelwork should either be protected during site storage or given a suitable
primer coat. The dry film thickness should be appropriate for the expected storage time and the severity of the
storage environment.
5.1.2.2 Maintenance
For maintenance of previously coated surfaces, the condition of the existing coating and the surfaces shall be
checked using suitable methods, e.g. ISO 4628-1 to ISO 4628-6, to determine whether partial or complete
repainting should be carried out. The type of surface preparation and protective paint system shall then be
specified. The paint manufacturer should be consulted for recommendations. Test areas may be prepared to
check the manufacturer's recommendations and/or the compatibility with the previous paint system.
5.2 Type of primer
Tables A.1 to A.8 in Annex A give information on the type of primer to be used. For the purposes of this part of
ISO 12944, two main categories of primer are defined according to the type of pigment they contain:
⎯ Zinc-rich primers, Zn (R), are those in which the zinc dust pigment content of the non-volatile portion of
the paint is equal to or greater than 80 % by mass.
⎯ Other primers (Misc.) are those containing zinc phosphate pigment or other anticorrosive pigments and
those in which the zinc dust pigment content of the non-volatile portion of the paint is lower than 80 % by
mass. Zinc chromate, red lead and calcium plumbates are not widely used for health and safety reasons.
For pre-fabrication primers, see Annex B.
The zinc dust pigment shall comply with ISO 3549.
NOTE 1 A method for the determination of the zinc dust pigment content of the non-volatile portion of a paint is
described in ASTM D 2371.
NOTE 2 The value of 80 % zinc dust by mass in the dry film for zinc-rich primers Zn (R) is the basis for the durability
given for the paint systems in the tables. Some countries have national standards with a minimum content of zinc dust for
zinc-rich primers Zn (R) higher than 80 %.
8 © ISO 2007 – All rights reserved
ISO 12944-5:2007(E)
5.3 Low-VOC paint systems
The examples listed in Annex A include paint systems with a low VOC content designed to meet requirements
for low emission of solvents.
For each corrosivity category, separate tables indicate whether the paints for the paint systems listed are
available as water-borne materials and whether they are available as a 1-pack or 2-pack. Several of the paint
systems listed can include either high-solids or water-borne paints for both the primer and the topcoating
materials, or a combination of high-solids and water-borne paints. For further information about VOCs,
see Annex D.
5.4 Dry film thickness
Definitions of dry film thickness (DFT), nominal dry film thickness (NDFT) and maximum dry film thickness are
given in 3.10, 3.11 and 3.12, respectively.
The film thicknesses indicated in Tables A.1 to A.8 are nominal dry film thicknesses. Dry film thicknesses are
generally checked on the complete paint system. Where judged appropriate, the dry film thickness of the
priming coat or of other parts of the paint system may be measured separately.
NOTE Depending on the instrument calibration, measurement method and dry film thickness, the roughness of the
steel surface will have a different degree of influence on the measurement result.
The method and procedure for checking the thicknesses of dry films on rough surfaces shall be in accordance
with ISO 19840, and for smooth and galvanized surfaces in accordance with ISO 2808, unless otherwise
agreed between the interested parties.
Unless otherwise agreed, the following acceptance criteria, as stated in ISO 19840, shall apply:
⎯ the arithmetic mean of all the individual dry film thicknesses shall be equal to or greater than the nominal
dry film thickness (NDFT);
⎯ all individual dry film thicknesses shall be equal to or above 80 % of the NDFT;
⎯ individual dry film thicknesses between 80 % of the NDFT and the NDFT are acceptable provided that the
number of these measurements is less than 20 % of the total number of individual measurements taken;
⎯ all individual dry film thicknesses shall be less than or equal to the specified maximum dry film thickness.
Care shall be taken to achieve the dry film thickness and to avoid areas of excessive thickness. It is
recommended that the maximum dry film thickness (individual value) is not greater than three times the
nominal dry film thickness. In cases when the dry film thickness is greater than the maximum dry film
thickness, expert agreement shall be found between the parties. For some products or systems, there is a
critical maximum dry film thickness. Information given in the paint manufacturer’s technical data sheet shall
apply to such products or systems.
The number of coats and the nominal dry film thicknesses quoted in Annex A are based on the use of airless
spray application. Application by roller, brush or conventional spraying equipment will normally produce lower
film thicknesses, and more coats will be needed to produce the same dry film thickness for the system.
Consult the paint manufacturer for more information.
5.5 Durability
Definitions of durability and of durability ranges are given in ISO 12944-1.
The durability of a protective paint system depends on several parameters, such as:
⎯ the type of paint system;
⎯ the design of the structure;
ISO 12944-5:2007(E)
⎯ the condition of the substrate before preparation;
⎯ the surface preparation grade;
⎯ the quality of the surface preparation work;
⎯ the condition of any joints, edges and welds before preparation;
⎯ the standard of the application work;
⎯ the conditions during application;
⎯ the exposure conditions after application.
The condition of an existing paint coating can be assessed by the use of ISO 4628-1, ISO 4628-2, ISO 4628-3,
ISO 4628-4, ISO 4628-5 and ISO 4628-6, and the effectiveness of surface preparation work can be assessed
using ISO 8501-1 and ISO 8501-3.
It has been assumed in compiling the tables in Annex A that the first major maintenance painting would
normally need to be carried out for reasons of corrosion protection once the coating has reached Ri 3 as
defined in ISO 4628-3. Based on this precondition, durability has been indicated in this part of ISO 12944 in
terms of three ranges:
a) low (L): 2 years to 5 years;
b) medium (M): 5 years to 15 years;
c) high (H): more than 15 years.
The durability range is not a “guarantee time”. Durability is a technical consideration that can help the owner
set up a maintenance programme. A guarantee time is the subject of clauses in the contract and is not within
the scope of this part of ISO 12944. There are no rules that link the two periods of time. See also 6.2. The
guarantee time is usually shorter than the durability range.
Paint systems classified between 5 years and 15 years durability are all classified as “medium”. It is essential
that users are aware of the wide extent of the medium durability range and take this into consideration when
developing specifications.
Maintenance is often required at more frequent intervals because of fading, chalking, contamination or wear
and tear, or for aesthetic or other reasons.
5.6 Shop and site application
To ensure maximum performance of a paint system, the majority of the coats of the system or, if possible, the
complete system, should preferably be applied in the shop. The advantages and disadvantages of shop
application are as follows:
Advantages Disadvantages
a) Better control of application a) Possible limitation of the size of the building
components
b) Controlled temperature b) Possibility of damage due to handling, transport and
erection
c) Controlled relative humidity c) Maximum overcoating time could be exceeded
d) Easier to repair damage d) Possible contamination of the last coat
e) Greater output
f) Better waste and pollution control
10 © ISO 2007 – All rights reserved
ISO 12944-5:2007(E)
After completion of fabrication on site, any damage shall be repaired in accordance with the specification.
NOTE Places where repairs have been carried out will always remain more or less visible. This is one reason why it
is better to put a topcoat over the whole surface on site when aesthetic aspects are important.
Site application of the coating system will be strongly influenced by the daily weather conditions, which will
also have an influence on the expected lifetime.
If preloaded bearing-type connections are to be painted, paint systems shall be used which do not lead to an
unacceptable decrease in the preloading force. The paint systems selected and/or the precautions taken for
such connections will depend on the type of structure and on subsequent handling, assembly and
transportation.
6 Tables for protective paint systems
6.1 Reading the tables
The tables given in Annex A give examples of paint systems for different environments. The shading used in
alternate lines is there purely for ease of reading. The dark-grey shading in the “Expected durability” columns
indicates the anticipated durability for that system. The paints used for all these systems shall be suitable for
the highest corrosion stress of the given corrosivity or immersion category. The specifier shall ensure that
documentation, or a statement from the paint manufacturer, is available confirming the suitability or the
durability of a paint system for use in a given corrosivity or immersion category. If required, the suitability or
durability of the paint system shall be demonstrated by experience and/or laboratory performance test
methods in accordance with ISO 12944-6 or as otherwise agreed.
The paint systems have been listed in the tables using two different principles:
a) Tables A.1, A.7 and A.8 list systems for more than one corrosivity category (Table A.1 is referred to
hereafter as the “summary table”). These systems have been arranged according to the binder used in
the topcoat. This arrangement is more convenient when the performance properties of the topcoat are
used as the basis for system selection, and for comparison of the overall durability of paint systems for
more than one corrosivity category when the corrosivity category is not known exactly.
b) Tables A.2, A.3, A.4, A.5 and A.6 (referred to in the following as “individual tables”) list systems for one
corrosivity category only (considering C5-I and C5-M as a single category). The systems have been
arranged according to the type of priming coat. This arrangement is convenient for users who know
exactly the corrosivity category of the environment to which their structure will be exposed.
NOTE The paint systems listed have been chosen as “typical systems”. This has led to some systems being listed
that are not necessarily typical or available in some countries. It has been concluded, however, that a simple overview
cannot be given, nor can all options be covered.
If a specifier intends to make use of the paint systems listed in the tables, he should first decide whether he
will use paint systems from the summary table or from individual tables because the system numbering is
different in the two types of table.
6.2 Parameters influencing durability
In practice, so
...
Frequently Asked Questions
EN ISO 12944-5:2007 is a standard published by the European Committee for Standardization (CEN). Its full title is "Paints and varnishes - Corrosion protection of steel structures by protective paint systems - Part 5: Protective paint systems (ISO 12944-5:2007)". This standard covers: ISO 12944-5:2007 describes the types of paint and paint system commonly used for corrosion protection of steel structures. It also provides guidance for the selection of paint systems available for different environments and different surface preparation grades, and the durability grade to be expected. The durability of paint systems is classified in terms of low, medium and high.
ISO 12944-5:2007 describes the types of paint and paint system commonly used for corrosion protection of steel structures. It also provides guidance for the selection of paint systems available for different environments and different surface preparation grades, and the durability grade to be expected. The durability of paint systems is classified in terms of low, medium and high.
EN ISO 12944-5:2007 is classified under the following ICS (International Classification for Standards) categories: 87.020 - Paint coating processes. The ICS classification helps identify the subject area and facilitates finding related standards.
EN ISO 12944-5:2007 has the following relationships with other standards: It is inter standard links to EN ISO 12944-5:1998, EN ISO 12944-5:2018. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.
You can purchase EN ISO 12944-5:2007 directly from iTeh Standards. The document is available in PDF format and is delivered instantly after payment. Add the standard to your cart and complete the secure checkout process. iTeh Standards is an authorized distributor of CEN standards.
La norme EN ISO 12944-5:2007 constitue un document essentiel pour le secteur de la protection anticorrosion des structures en acier. Son champ d’application est clairement défini, englobant les types de peintures et de systèmes de peinture utilisés couramment pour la protection contre la corrosion. Cette norme fournit des orientations précieuses pour le choix des systèmes de peinture adaptés à différents environnements et à divers grades de préparation de surface. Un des points forts de cette norme est sa classification de la durabilité des systèmes de peinture en trois catégories : faible, moyenne et élevée. Cette approche permet aux professionnels de prendre des décisions éclairées en matière de choix de produits, garantissant ainsi une protection adéquate en fonction des conditions spécifiques auxquelles les structures en acier seront exposées. La pertinence de la norme EN ISO 12944-5:2007 réside également dans sa capacité à adapter les recommandations aux diverses applications industrielles, ce qui en fait un outil indispensable pour les ingénieurs et les responsables de la maintenance. En s’appuyant sur des critères clairs et des conseils pratiques, cette norme facilite l’optimisation des performances des systèmes de peinture, tout en contribuant à la durabilité et à la longévité des constructions en acier face à la corrosion. En somme, la norme EN ISO 12944-5:2007 représente une référence incontournable pour quiconque s'engage dans la protection anticorrosion des structures en acier, assurant ainsi efficacité et pérennité dans les choix de systèmes de peinture.
SIST EN ISO 12944-5:2009 표준 문서는 철강 구조물의 부식 보호를 위한 도료 및 도료 시스템의 사용에 대한 포괄적인 지침을 제공합니다. 이 표준은 다양한 환경과 표면 준비 상태에 따른 도장 시스템 선택을 위한 명확한 지침을 제공하며, 도장 시스템의 내구성 등급을 저, 중, 고로 분류하고 있습니다. 이 표준의 강점 중 하나는 철강 구조물의 부식 방지를 위한 도료 선택 시 고려해야 할 환경적 요인과 적절한 표면 처리 방식에 대한 체계적인 정보를 제공한다는 점입니다. 특히, 다양한 내구성 등급에 대한 정의와 기준이 명확하여 사용자가 특정 조건에 맞는 도료를 쉽게 선택할 수 있습니다. 또한, EN ISO 12944-5:2007은 시간이 지남에 따라 변화할 수 있는 환경적 요인에 따른 내구성 평가 기준을 제시함으로써, 특정 영구적 사용 환경에 적합한 도장 시스템을 선택할 수 있게 해줍니다. 이는 산업 전반에 걸쳐 도료 선택의 일관성과 신뢰성을 높이는 데 기여합니다. 결론적으로, SIST EN ISO 12944-5:2009는 철강 구조물의 장기적인 내구성을 보장하기 위한 매우 중요한 표준으로, 품질 높은 도료 시스템을 선택하는 데 있어 필수적인 참고자료가 될 것입니다.
EN ISO 12944-5:2007は、鋼構造物に対する腐食保護のための塗料および塗料システムについて詳細に説明している重要な標準です。この標準は、さまざまな環境条件や表面準備の程度に応じて利用可能な塗料システムの選定に関する指針を提供し、塗料システムの耐久性を低、中、高の3つのグレードで分類しています。 この標準の強みは、広範囲にわたる腐食防止塗料システムの具体的な種類を明確に定義している点です。鋼構造物の保護に関する専門知識を持たないユーザーであっても、適切な塗料システムを選ぶための有用な情報を得ることができます。また、この標準は、塗装を行う際の環境条件に対する配慮を奨励しており、塗料の耐久性についての期待を明確に示すことで、実務に役立つ指針を提供しています。 さらに、ISO 12944-5:2007は、長期間にわたって信頼性の高い保護が求められる施設や構造物において、適切な塗料の選択とその準備が重要であることを強調します。このような点において、塗料の選定に関する系統的なアプローチを確立することに寄与しており、業界の基準を向上させる一助となっています。 SIST EN ISO 12944-5:2009は、EN ISO 12944-5:2007に基づいており、国際的な標準に準拠することで、さらなる信頼性と標準化を実現しています。腐食防止塗料システムの選定において、業界全体にわたる共通の理解を促進することが、この標準の重要な役割と言えるでしょう。
Die Norm EN ISO 12944-5:2007 bietet eine umfassende Richtlinie für die Beschichtung und den Korrosionsschutz von Stahlkonstruktionen durch Schutzanstriche. Der Umfang dieser Norm reicht von der Beschreibung der unterschiedlichen Farb- und Anstrichsysteme, die häufig für den Korrosionsschutz von Stahl verwendet werden, bis hin zur Anleitungen zur Auswahl geeigneter Anstrichsysteme, die an verschiedene Umgebungen und Oberflächenvorbereitungsgrade angepasst sind. Ein starkes Merkmal dieser Norm ist die klare Klassifikation der Haltbarkeit von Anstrichsystemen. Diese wird in drei Kategorien unterteilt: niedrig, medium und hoch. Diese Einteilung ermöglicht es Fachleuten, fundierte Entscheidungen bezüglich der Langlebigkeit und der Leistung der verschiedenen Anstrichsysteme zu treffen. Darüber hinaus ist die Norm von erheblicher Relevanz für die Industrie, da sie Experten dabei unterstützt, effektive und langlebige Lösungen zur Bekämpfung von Korrosion zu finden, die für unterschiedliche Bedingungen und Anwendungen geeignet sind. Der sorgfältige Ansatz zur Auswahl und Anwendung der Schutzanstriche in EN ISO 12944-5:2007 fördert eine verbesserte Lebensdauer von Stahlkonstruktionen und trägt zur sicheren Nutzung dieser Materialien bei.
The EN ISO 12944-5:2007 standard is a comprehensive document that addresses the essential aspects of corrosion protection for steel structures through protective paint systems. Its primary scope encompasses the identification and evaluation of various types of paints and paint systems that are applicable for enhancing the durability of steel structures exposed to different environmental conditions. One of the significant strengths of this standard lies in its detailed guidance on the selection of appropriate paint systems based on specific environmental factors and surface preparation grades. This is particularly crucial for industries that rely on the structural integrity of steel, as it allows for tailored solutions that take into account varying exposure conditions and service life expectations. The categorization of paint system durability into low, medium, and high grades not only aids in informed decision-making but also sets clear expectations for performance, thereby facilitating better project planning and resource allocation. Moreover, the relevance of the EN ISO 12944-5:2007 standard cannot be overstated, particularly in sectors where corrosion is a primary concern. By providing a framework for selecting protective paint systems, it supports professionals in ensuring long-lasting protection of steel structures against environmental wear, which is essential for safety and cost-efficiency. This standard is instrumental for industries such as construction, infrastructure, and manufacturing, where the longevity and maintenance of steel structures are critical. In summary, EN ISO 12944-5:2007 serves as a vital resource for engineers and project managers, delivering authoritative guidance on protective paint systems that enhance corrosion resistance, tailored to various operational contexts, and ensuring the durability of steel structures over time.
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