How To Use SSPC Standards and Guides

The SSPC Standards and Guides

SSPC: The Society for Protective Coatings

About SSPC Standards and Guides

1. SSPC Consensus Documents

SSPC’s Technical Committees develop both manda­tory documents (standards, standard procedures, methods, or specifications) to be used in preparation of procurement documents for painting work, and non-mandatory documents (guides, technology updates, technology reports, and technol­ogy guides) that provide guidance in current good practice. These documents are the product of many years of broad open consensus work by the SSPC staff and by the leading specialists in each field of protective coatings technology. In this section, the term “standards” is used to encompass both mandatory and non-mandatory documents.

In addition to standards developed by SSPC techni­cal committees, peer-reviewed commentaries that provide background information about groups of related standards, and a peer-reviewed monograph discussing proper monitoring of ambient conditions are available.

2. Definitions
SSPC consensus documents use terms such as specifica­tion, commentary, guide, or notes as indicated below:

Standard: A specification, practice, or test method that has been formally adopted. SSPC standards include specifications and guides, each of which may refer to other standards.

Specification: A detailed description of requirements of a product or process that can be incorporated into a procure­ment document.

Method: A form of standard describing a precise procedure or technique used for performing a specific task.

Painting System: A term intended to include, with equal emphasis, not only the well accepted components of a system such as surface preparation and paint materials, but also the application, inspection, and safety functions.

Painting System Materials Specification: A specification that covers only the paint in a multi-coat system without specify­ing surface preparation, film thickness, and application.

Coating System: A term which refers to the applied and cured multi-layer film or to the components of a system based on non-paint type coating such as thermal spray coatings.

Commentary: Explanatory remarks at the beginning of a chapter, describing the background and proper use of the specifications and guides. (This is not a part of the specifica­tions and guides, but often is important in their selection and use.)

Guide: A set of instructions or organized information based on a consensus of “best industry practice.”  Material contained in a non-mandatory guide may be extracted and used in preparation of procurement documents, although the guide itself is not suitable for reference in procurement documents because it does not contain mandatory language. Painting System Guides are coded SSPC-PS Guide 1.00, 2.00, 3.00, 4.00, etc. and are to be used to select painting system speci­fications. The guides to safety in paint application (SSPC-PA Guide 3) and maintenance (SSPC-PA Guides 4 and 5) aid in establishing standard practices, procedures, and specifications for coating application and maintenance.

Notes: Additional information at the end of a specification that is not considered a mandatory requirement.

Qualification Procedure: A procedure that defines a sequence of actions or functions an individual or organi­zation must meet to establish or verify a specified level of competence.

Joint Technology Report: A report issued by an SSPC/NACE technical committee to address the state of the art of a particular technology.

Technology Update: A consensus SSPC document prepared by a committee that describes and assesses a new material, procedure, concept, method, or other area of technology. Technology Updates are considered “fast track” documents and skip some steps in the standards approval process. A Technology Update is not suitable for referencing in a specification or procurement document because it does not contain mandatory language, although information from a Technology Update may be extracted and referenced in a contract. It differs from a technical article in a journal in that it represents a consensus of balanced interests, not a single author’s viewpoint.

Other terms sometimes used in the industry include: practice—A form of standard that is a procedure, guide, or service that may or may not be auxiliary to a test method or a specification; test method—A form of standard that covers sampling and subsequent testing procedures used in determin­ing the properties, composition, or performance for materials, products, systems, or services that may be specified. A test method does not include the kind of numerical limits for the properties, composition, or performance that should normally be included in a specification. Other terms are covered in the Glossary section of Volume 1 of the SSPC Painting Manual and in the SSPC Protective Coatings Glossary (SSPC 00-07).

4. Identification Numbers Used for SSPC Standards, Specifications, and Guides

Designations for the SSPC standards, specifications, technology reports, technology updates, and their abbreviations are listed below. The term “Paint,” used as the designation for SSPC Paint Specifications, is the only term not abbreviated.

PS = Painting System

CS = Coating System

Paint = Paint (or Coating)

SP = Surface Preparation

AB = Abrasive

PA = Paint Application

QP = Qualification Procedure

ME = Method (of preparing test panels)

TR = Technology Report

TU = Technology Update

The word “Guide” is placed before the number portion of the identification for those documents that are Guides; for example, PA-Guide 3.

The latest issue of the document is to be used unless otherwise specified.

5. Methods of Using SSPC Painting System Specifications

Using Specifications Without Modifications or Amend­ments. Each painting system specification may be used in its entirety, by proper reference in the procurement documents, to cover all usual requirements for the intended use. To do this, simply specify that the steel or structure shall be painted “in accordance with SSPC-PS ____.” Used without modification, these SSPC painting systems cover many of the normal painting problems that are encountered. Since each painting system describes the minimum requirement for the intended service, it follows that better methods or materials may be substituted without prejudice, provided the practical value of the improve­ment is judged to be commensurate with the added cost.

Modifications of Specifications. Modifications to reflect the needs of an individual project may be made by the preparer by reviewing each item of the applicable specification and then including his decisions on variations as mandatory requirements in the procurement documents. To do so, modify a standard specification by adding, deleting, or changing requirements.

Use of Painting System Guides. The preparer may use the Painting System Guides SSPC-PS Guide 1.00, 2.00, 3.00, etc. to prepare his/her own modified painting systems for special cases not covered by the standard systems. Recommendations for special conditions are shown in Table 1.

6. Selection of Painting Systems by Environ­mental Zone

General Considerations. Because of the wide diversity of available systems, the adverse conditions under which they must sometimes be applied, environmental restrictions, and the need for minimizing maintenance, the choice of a suit­able painting system is not always an easy one. There is, of course, no one “best” painting system, but rather a dynamic competition among alternative materials and methods whose choice often depends upon both technological factors and policy considerations. Since environmental factors are often the dominant ones, they will be considered first, followed by other important con­siderations such as cost, appearance, and design.

Effects of Environment on Corrosion Rates. Among the technological factors in the choice of a painting system, environment is usually the controlling one. For example, one rule of thumb advocates that steel need not be painted at all when the corrosion rate is uniform and below a certain level; on the other hand, alternative materials of construction should be considered instead of painting when the environment is too severe. Table 2 illustrates the wide range of atmospheric corro­siveness as measured by  ASTM.  In some areas, increased atmospheric contamination has resulted in acid rain waters,  but many industrial locations have become less contaminated than in the recent past.

Environmental Zones: A concise description of each SSPC “environmental zone” is given in Table 3, while Table 4 indicates typical painting system(s) recommended for minimum performance in each zone. These zones cover rural, urban, commercial, and marine environments and several special exposures. Use of the term “environmental zone” in this con­text is not meant to parallel the common meaning of the term, which implies geographical location but, rather, defines the type of environment (atmosphere) to which the coated steel will be exposed. As an example of this more specialized mean­ing of environmental zone, consider a steel framed building, part of which is devoted to office space, and another part of which is devoted to chemical laboratory and pilot plant space where acidic fumes are frequently generated. Each of these areas is exposed to a significantly different environment. An­other example is the roadway and superstructure of a bridge located in a geographical area where freezing and road salt use are common. The upper portions of such a bridge have to be protected only against weather exposure, whereas the roadway steel and adjacent structural components must also be protected against de-icing salt in solution.

For purposes of classifying environmental exposures according to their severity, they have been divided into envi ronmental zones from essentially non-corrosive dry interiors (Zone 0) to severe chemical exposures (Zone 3). Special conditions are listed in Table 1. Exposure conditions may be such as to require little or no protection by painting; conversely, they may indicate the need for elaborate surface preparation, pretreatment, and properly selected primer, intermediate, and finish coats. Although Table 4 may indicate several different generic painting systems suitable for use in a particular zone, some systems are more durable than others and will achieve
better performance or longer coating life.

This classification of environment is probably the most useful type of designation, since most available data on paint exposures is defined in these broad terms. Factors such as time-of-wetness, chloride level, sulfur dioxide content, pH, conductivity, surface contamination, etc., should also be con­sidered when choosing a painting system. In Table 4, Painting System numbers have been rounded off to show the generic class of systems that are satisfactory. For example, SSPC-PS 15 includes Painting System Guide 15.00 and Painting System Specifications SSPC-PS 15.01 through 15.04.

Such guides as Table 4 are intended to aid the specifier in selecting a painting system (including surface preparation, coatings, and application) but are, of course, no substitute for the knowledge and judgment entailed in an intelligent choice.

Influence of Geographical Locations on Environmental Zones:

Inland, rural locations, far from coastal salt water, are free from the corrosive influence of airborne salt. The presumption that the atmosphere in these areas, located far from centers of heavy industry, are therefore “virtually unpolluted,” has been drastically reversed. It is now seen that even rural locations, hundreds of miles distant from industrial plants and electrical power generating stations, can sometimes be subjected to acid rain generated by sulfur dioxide emissions. Rain water with a pH as low as 3-4 has been observed not only in rural, but also in wilderness locations. Therefore, preparers of painting system specifications must now cultivate a realistic awareness of present atmospheric conditions prevailing in rural locations that were traditionally considered benign with respect to cor­rosion of steel. Heavy industrial environments, such as those involving coke plants, are severe enough to be classified in the chemical category. These environments are marked by reduced paint life and high corrosion rates.

Marine atmosphere is typified by frequent and relatively high concentrations of salt mist, but it does not imply direct contact with salt spray or splashing waves; it contains a high concentration of chlorides in contrast to the high concentration of sulfur dioxide in the industrial atmosphere.

Fresh and salt water immersion have important differ­ences because of osmotic and electrolytic effects.

Alternate immersion refers to frequent, perhaps fairly long immersion in water alternated with exposure to the atmo­sphere above the water—for example, the boottopping area of a ship’s hull, or steel in the tidal range.

Condensation and high humidity exposure refers to almost continuous condensation; exposure to high humidity alone (with little or infrequent condensation) is not considered to be in this class of exposure.

Chemical environments are those in which strong concen­trations of highly corrosive gases, fumes, or chemicals—either in solution, or as concentrated liquids or solids—contact the surface. The severity of exposure may vary tremendously from mild concentration in a yard area to direct immersion in the chemical substance.

Underground refers to buried surfaces in direct contact with the soil, which may be high in salinity or acidity.
It should be understood that surfaces presumed to be exposed to the weather are indeed open to the elements. Structures open to pollution, but sheltered from rain, are par­ticularly vulnerable.

Special Service Requirements. Some painting systems for special services, including resistance to abrasion, fouling, graffiti, mildew, and skidding, are listed in Table 1.

7. Other Factors in Painting System Selection

Although environment is usually the primary factor in the choice of a coating system, other factors such as costs, application, surface preparation, appearance, design, avail­able facilities, and availability of specifications should also be considered.

Costs per unit area per year should really be minimized over the projected life of the structure. Sophisticated engineering calculations are sometimes justified, since the cost of coatings during the total life cycle of a structure often exceeds the initial cost of the structure itself. At times in the economic cycle these cost calculations are simplified when money interest rates are of the same order of magnitude as the inflation rate. During these periods a dollar set aside initially at current interest rates may be presumed to have the same purchasing power when it is ready to be spent at some future date.

In many cases it is more economical to use a “deluxe” painting system (for example, top-coated zinc-rich over near-white blast cleaned steel as per SSPC-PS 12.00) than a “low cost” system (such as SSPC-PS 1.09) in a situation where the life of the latter is five years or less.

In many U.S. environments, however, a coating life of seven or more years can be obtained with a simple alkyd paint system. Here it becomes more difficult to justify on a purely economic basis the high initial cost entailed in a potentially more durable system. Such systems usually involve more expensive surface preparation and application and are less tolerant of lapses in workmanship. The cost of the paint itself is, of course, a relatively minor consideration since surface preparation and application costs are usually from two to ten times the material costs.

Appearance is a major consideration in painting many bridges, tanks, refineries, plants, etc., and color is often chosen to harmonize or contrast with adjacent topographic or com­munity features. Appearance plays an increasingly important role in structural painting, but corrosion prevention is necessary to retain that appearance.

Engineering Design of a steel structure can often render protection by paint either relatively straightforward or almost impossible. Chapter 1.2 of Volume 1 of the SSPC Painting Manual, 4th ed., discusses alternative coating practices which should influence the design of structures. These include designs that provide for adequate drainage to avoid entrapment of water; avoidance of crevices that prevent satisfactory application of paint both in original painting and in maintenance painting; and avoidance of sharp edges, either by original rolling to edges with a reasonable radius, or by the requirement of grinding off sharp outside corners.

Facilities Available or methods permissible sometimes limit the type of surface preparation, application, or coatings that can be specified. Sometimes where blast cleaning is im­practical or prohibited, the use of high performance coatings that demand rigorous surface preparation must be bypassed in favor of oil base or alkyd paints, or high solids penetrating epoxies (epoxy mastics), or urethanes possessing lesser resis­tance properties but greater penetration and better tolerance for residues of rust, oil, and dirt.

Sequence. All elements of the system should be sequen­tially compatible: the surface preparation with the primer, the primer with the intermediate paint(s), and so on to the finish coat.

Availability of Specifications is essential for many types of public and private structures in the U.S., where policy encour­ages the procurement of materials and services on an open competitive basis. Performance criteria are used whenever possible, but in practice, composition requirements must also be included. Some users also prefer to specify by proprietary product name based upon proven past performance or by qualified products lists.

Environmental Constraints are causing the industry to look carefully at alternatives to sand blasting, at new inhibitive types of pigment, and at new coatings with very low volatile organic compound (VOC) content. Much surface preparation work, for example, is concerned with removal of blast residue, with the use of low-free-silica nonmetallic abrasives, with the use of metallic and other recyclable abrasives, with new wet blast techniques, and with entirely new surface preparation concepts.

Shop Painting Versus Field Painting Versus Deferred Painting. In new work it is common to carry out the surface preparation and priming in the shop, touch-up in the field, and finish coating after erection. Other practices are sometimes followed, such as deferring the second coat of paint for several years when the original primer was a zinc-rich. This practice may have tax advantages and has often proven technically feasible. However, postponing the second coat of an oleoresin­ous paint more than six months can be disastrous and is not recommended.

Contract Painting Versus “In-House” Painting. Many large users have their own highly qualified full-time crews, whereas others favor the use of a knowledgeable contractor whose sole business is painting. The painting contract usu­ally provides for either a “cost plus” basis (at a competitive overhead rate) or a “hard dollar” basis, usually based upon competitive bidding.

Annual Fee Painting is a type of painting contract in which the contractor agrees, for a specified annual fee, to do whatever painting is necessary to maintain a given plant at a specified high level of protection (e.g., SSPC-VIS 2, Rust Grade 8 or better). This arrangement provides an incentive to minimize cost without sacrificing quality.

8. Additional References

Volume 1 of the SSPC Painting Manual offers background on the selection of painting systems in a wide range of indus­tries and environments: steel, petroleum, water, food, paper, power, chemical, highway, railway, salt water, fresh water, tank building, hydraulics, underground, sewage, and government installations. It also presents a background on corrosion, all types of surface preparation, coatings materials, application, inspection, costs, design, failure prevention, and sources of other information.

SSPC’s Journal of Protective Coatings and Linings (JPCL) is a monthly publication that covers all aspects of protective coatings technology for a wide variety of industries.

TABLE 1 TYPICAL RECOMMENDATIONS FOR SPECIAL SERVICE CONDITIONS
Abrasion Resistance	– Urethane coatings probably have more abrasion resistance per mil than any other organic generic class. These are available as proprietary materials. – Epoxies such as modified SSPC-PS 13 can be specially formulated so that removal, even by blast cleaning, is difficult, especially when they are sand-filled. – Zinc-rich coatings, such as SSPC-PS 12, especially the inorganic types, tend to “polish” and not abrade off steel surfaces. – Coal tar epoxy paints, such as SSPC-PS 11, or selected proprietary products, especially when filled with garnet or other hard 30 to 70 mesh materials. – SSPC-PS 2, 3, 4, 10, 11, or 13 when sand-filled. – Gravel, sand, slate granules in SSPC-PS 9 or 10.
Anti-Sweat	Preformed plastic and foam spray have superseded paints for most anti-sweat functions.
Anti-Fouling	These paints are covered in SSPC-PS 19 and in Chapters 6.11 and 9.3 of the SSPC Paint­ing Manual, Vol. 1.
Protection from Graffiti	See SSPC-PS 17 and polyester urethane guides with recommended ratios of polyol, isocyanate, and NCO.
Skid Resistance	Any type of paint that is suitable for application on floors can be converted to a specifically skid resistant paint by incorporation of a finely divided material such as silica, aluminum oxide, or ground shells.
Mildew Resistance	1. Wash with phosphate-free detergent. 2. Rinse with a solution of one part sodium hypochlorite (Hilex, Clorox, Purex, etc.) and three parts water. Allow some dwell time before a final rinse. 3. Use a paint suitable for specific surface and exposure
Piping	Color codes for identifying piping are given in ANSI A13.1, “Identification of Piping.”
Safety Colors	Standards for safety colors are given in ANSI Z53.1, “Color Coding.”
Wet Surfaces	Some epoxies and urethanes have been successfully applied to wet surfaces.
Cold Surfaces	Some urethanes can be applied to cold surfaces. Cycloaliphatic amine-cured epoxies can be used.
Underwater	Epoxies have been developed for underwater application. (Some urethanes will cure underwater but cannot be applied underwater.)
Rebar Protection	Fusion bonded epoxies or hot dip galvanizing.

TABLE 2 SOME MEASURED CORROSION RATES1
Site No.		Location		Type of Atmosphere		Relative Rating

Steel

Zinc

1		Normal Wells, N.W.T.		Rural		0.02		0.2
2		Saskatoon, Sask.		Rural		0.2		0.2
9		State College, PA2		Rural		1.0		1.0
17		Pittsburgh, PA (roof)		Industrial		1.8		1.5
18		London (Battersea)		Industrial		2.0		1.2
27		Bayonne, NJ		Industrial		3.4		3.1
28		Kure Beach, NC (250 m)		Marine		3.6		1.9
31		London (Strafford)		Industrial		6.5		4.8
33		Point Reyes, CA		Marine		9.5		1.0
37		Kure Beach, NC (25 m)		Marine		33.0		6.4

¹ Adapted from ASTM Materials Research and Standards, December, 1961, page 977.

² State College, PA was taken as unity. Fortuitously, a relative rating of 1.0 represented about 1 mil loss the first year.

TABLE 3 SSPC ENVIRONMENTAL ZONES
0	Dry interiors where structural steel is imbedded in concrete, encased in masonry or protected by membrane or non-corrosive contact type fireproofing.
1A	Interior, normally dry (or temporary protection). Very mild (oil base paints now last six years or more).
1B	Exteriors, normally dry (includes most areas where oil base paints now last six years or more).
2A	Frequently wet by fresh water. Involves condensation, splash, spray or frequent immersion. (Oil base paints now last five years or less.)
2B	Frequently wet by salt water. Involves condensation, splash, spray, or frequent immersion. (Oil base paints now last three years or less.)
2C	Fresh water immersion
2D	Salt water immersion
3A	Chemical atmospheric exposure, acidic (pH 2.0 to 5.0)
3B	Chemical atmospheric exposure, neutral (pH 5.0 to 10.0)
3C	Chemical atmospheric exposure, alkaline (pH 10.0 to 12.0)
3D	Chemical atmospheric exposure, presence of mild solvents. Intermittent contact with aliphatic hydrocarbons (mineral spirits, lower alcohols, glycols, etc.)
3E	Chemical atmospheric exposure, severe. Includes oxidizing chemicals, strong solvents, extreme pH’s or combina­tions of these with high temperatures.

TABLE 4 ENVIRONMENTAL ZONES FOR WHICH SSPC PAINTING SYSTEMS ARE RECOMMENDED

PAINTING SYSTEM

ENVIRONMENTAL ZONE

SSPC #

GENERIC TYPE

0

1A

1B

2A

2B

2C

2D

3A

3B

3C

3D

3E

PS 1

Oil base

X

X

PS 2

Alkyd

X

X

PS 3

Phenolic (oleoresinous)

X

X

X

PS 4

Vinyl

X

X

X

X

X

X

X

PS 7

One-Coat shop

X

X

PS 9

Cold applied asphalt mastic

X

X

X

X

PS 10

Coal Tar mastic or enamel

X

X

X

PS 11

Coal Tar Epoxy

X

X

X

X

X

X

X

PS 12

Zinc-rich (untopcoated)

X

X

X

X

X

X

X

X

PS 12

Zinc-rich (topcoated)

X

X

X

X

X

X

X

X

X

PS 13

Epoxy Polyamide (non-immersion)**

X

X

PS 14

Steel Joist Shop Paint

X

PS 15

Chlorinated Rubber

X

X

X

X

X

X

X

X

PS 16

Silicone Alkyd

X

PS 17

Urethane

X

X

X

X

PS 18

Latex

X

X

PS 19

Ship bottoms

X

PS 20

Ship boot toppings

X

X

PS 21

Ship topsides

X

X

X

X

PS 22

One-coat pre-construction

X

X

CS 23

Thermal spray metallic

X

X

X

T

X

T

T

T

T

PS 24

Latex (performance-based)

X

X

X*

X*

X

X

X

X

PS 26

Aluminum Epoxy (performance-based)

X

X

X*

X*

PS 27

Alkyd (performance-based)

X

X

X*

X*

NOTES:

Zones for use are those recommended by the committee that developed the specification.

PS 4 (vinyl) and PS 15 (chlorinated rubber) do not meet VOC restrictions and are rarely used.

** For immersion service, proprietary epoxy and urethane coatings are usually used.

T = Recommended only with proper sealing or topcoating

PS 26 and PS 27 are material specifications and cover only the paint.

* = Excluding immersion

For Zone 3E use specific exposure data to select a coating.

Because more than one system is recommended for a particular zone does not mean that they will all perform equally well.

SSPC: The Society for Protective Coatings – About SSPC Standards and Guides