ISO 12944

DEFG

ISO 12944 Module 7 Introduction

Like many industrial sectors, the Protective Coatings Industry has standardisation associated with it Standardisation is required in order to ensure best practice and a specified level of quality is achieved When it comes to the issue of corrosion protection via the use of protective coatings, it is fair to say that most regions or countries of the world may have their own standardisation & quality requirements that needs to be adhered to Where countries don’t have their own, they tend to ‘borrow’ from the more recognised standards such as those provided by SSPC, NACE, DIN or BS In addition, some customers, such as those associated with oil & gas, will adopt these standards and use them as a framework in developing their own ‘internal’ standardisation & quality requirements From an IPC point of view, trying to satisfy all the requirements of the many individual, regional and local standards currently in place is an impossible task, and only makes the implementation of a global strategy and product range even more complex It is important that IP as a truly global company should direct its focus on a truly global coatings standard and by that we mean those standards developed by ISO ISO = International Standards Organisation (www.iso.org) – it is based in Switzerland and is responsible for the standardisation and documentation of numerous procedures and testing regimes The use of ISO standards fits well with IPC global strategy and allows us to put more focus on adopting and promoting the principles on a truly international stage ISO standards are available worldwide and in many different languages much like our own global product range associated literature such as datasheets & brochures etc This module focuses upon the ISO 12944 international standard which covers ‘corrosion protection of steel structures by protective paint systems’

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ISO 12944 Module 7 ISO 12944 – What is it?

In the mid 1990’s the coatings industry & corrosion experts from all over the world came together to form a committee to look into the standardisation of corrosion control at new construction After years of work, the result was the standard ISO 12944 – “Corrosion Protection of Steel Structures by Protective Paint Systems” ISO 12944 comprises of 8 parts which deals with all the aspects that are important in achieving adequate corrosion protection of steel structures when using protective coatings at new construction ISO 12944 – Who uses it? The standard is intended to be used by structure owners, engineers, consultants, fabricators, applicators and corrosion inspectors who have some knowledge of corrosion to assist in adopting best practice in corrosion mitigation via the use of protective coatings Utilising ISO 12944 at the new construction stage will help to minimise the need for coating maintenance which in turn helps to reduce health & safety concerns, environmental impact and overall structure lifetime costs Another key benefit of using ISO 12944 is that it can help to standardise the terminology and definitions used within the coatings industry This in turn helps to avoid misunderstanding of information which passes between the many different parties involved in a new construction project Everybody is talking the same language When considering the complex sales chain involved in certain PC projects, the use of ISO 12944 throughout the chain can help to reduce complexity and provide unambiguous and easily understandable communications in which all parties can relate to A ‘common language’ amongst all those involved in the sales chain ISO 12944 was released in 1998 and it has rapidly replaced local standards in Europe e.g. BS5493 and DIN55 928 It has also been adopted where no strong local standards are in place

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ISO 12944 Module 7

Within the Americas and Australasia where NACE/SSPC and AS/NZ standards are well established respectively, the switch to ISO 12944 is less advanced, however it is growing in popularity in these areas A large section of our potential customers will not be aware of ISO12944, it is everybody’s responsibility to take the lead and introduce it Many engineers prefer dealing with ISO - it is an independent, internationally recognised organization By promoting ISO 12944 within the market, International Protective Coatings can be seen as global, proactive in the industry, willing to accept impartial standards and taking a responsible approach to coating specification ISO 12944 – The concept In the broadest terms, ISO12944 makes use of 3 parameters when dealing with the corrosion protection of steel structures at New Construction Durability - The expected lifetime of a protective coating system prior to the first MAJOR maintenance. It is assumed that regular coating inspection and minor maintenance will always be required throughout the structure design life Corrosivity – The ability of an environment to cause corrosion, (taking into consideration any special conditions which may affect the performance of a protective coating system) Coating System Specification – The recommended coating system generic type which will provide the necessary corrosion protection to meet the both the durability and corrosivity demands. (this includes surface preparation) The development of the ISO 12944 standard has had a significant impact on the protective coatings industry since its release from both the perspective of the customer – be that an engineer, architect, fabricator, applicator – and the coating manufacturer Anybody who is involved with the provision of advice within the protective coatings industry should have a level of understanding of what ISO 12944 is all about This module summarizes IP’s viewpoint, however, it is not a substitute to actually reviewing the standard itself. It is recommended that you read the actual ISO 12944 standard in conjunction with this module

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ISO 12944 Module 7 ISO 12944 – The Parts

As already mentioned, ISO 12944 covers all aspects of protective coatings and consists of 8 parts, these are Part

Description

1

General Introduction

2

Classification of Environments

3

Design Considerations

4

Surface Preparation

5

Protective Paint Systems

6

Laboratory Test Methods

7

Execution / Supervision of Paint Work

8

Development of Specifications

ISO 12944 Part 1 – General Introduction ISO 12944 Part 1 describes the general scope of the entire standard and makes an early reference to protective functions that are not covered These are functions such as anti-fouling (e.g. Intersleek), storage of chemicals and ballast (e.g. Interline, Intershield), and fireprotection (e.g. Chartek & Interchar) Although not mentioned specifically, the ISO 12944 standard does not cover high heat areas (e.g. Intertherm) The specification of coating schemes involving Interline, Chartek, Intersleek & Intertherm are highly specialised Therefore they require more detailed information, guidance and testing to ensure successful use • This ‘detail’ can be difficult to capture in a standard such as ISO 12944 which covers such as broad range of corrosion protection issues The key element of part 1 revolves around the definition of the term ‘Durability’ and the expected lifetime of a protective coating system Within ISO 12944, durability is expressed in terms of 3 ranges, Low, Medium & High

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ISO 12944 Module 7

An alternative way of describing durability is in terms of ‘coating design life’. Many engineers, who will use ISO 12944, can better relate to the term design life. In many cases it is what they are trained to understand Low (L)

2 to 5 years

Medium (M)

5 to 15 years

High (H)

>15 years

When talking about coating durability or coating design life, there are some important considerations that must be taken into account. These are :•

The coating design life is dependent upon the degree of surface preparation. In most cases it is assumed that a minimum of Sa2½ cleanliness (~SSPC SP6) is achieved prior to coating application

•

The design life of the coating system is generally shorter than the expected design life of the structure it is protecting. Design life is best described as the level of coating failure (or breakdown) prior to the first MAJOR coating maintenance work is required

•

As such, due consideration must be made to ensure regular coating inspection and expected minor maintenance is carried out over the specified design life

The definition of MAJOR maintenance should be agreed by all interested parties in accordance with the standardised degradation of paint coatings described in ISO 4628 parts 1,2,3,4 & 5 Coating design life is not a guarantee time; therefore, ISO12944 offers a standard method of avoiding lengthy and unrealistic “lifetime guarantees” whilst still offering a meaningful coating design life. This all adds up to helping IPC manage liability from a commercial point of view Most IPC customers will focus their attention towards the high durability >15 year design life. In most cases, customers will require coating systems applied at new construction to last as long as possible in order to postpone the need for inconvenient major maintenance work Durability (or coating design life) only refers to corrosion protection. This should not be confused with durability in terms of colour & gloss retention of high performance finishes. There will potentially be the need for aesthetic upgrades

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ISO 12944 Module 7

The use of high performance finishes such as the polysiloxane products (Interfine 878 & Interfine 979) can help to reduce the number of ‘cosmetic upgrades’ that are required during the lifetime of a structure. This contributes to lowering overall structure lifetime costs ISO 12944 Part 2 – Classification of Environments This was briefly covered in the ‘Environment’ technical module; however, we will go into a little more detail The key feature of part 2 is that it provides a way of defining environments in terms of corrosivity in which steel structures are situated • These environments are known as Corrosive Categories This provides a very useful tool when considering an appropriate coating specification – in other words, it’s a very good starting point Understanding corrosive categories and environments helps to understand WHY & HOW certain coating products are used to prevent corrosion ISO 12944 Part 2 splits the environments into 3 main groups, they are atmospheric, immersion in water and buried in soil Atmospheric The atmospheric environments are classified into 6 corrosive categories defined from weight loss of metallic (low carbon steel and zinc) specimens over a defined period of 1 year The table on the next slide defines the corrosive categories in terms of steel mass loss and gives examples of typical exterior and interior environments In simplistic terms, as the steel mass loss increases, the corrosion rate increases, therefore the greater the atmospheric corrosivity Categories are designated as C1, C2….through to C5-I industrial and C5-M offshore

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ISO 12944 Module 7 Corrosive Category

Mass Loss / thickness Exterior Environment loss Examples

C1, C2 Very Low, Low C3 Medium