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SSPC-Paint 29 February 24, 2014

SSPC: The Society for Protective Coatings

Coating Specification No. 29

Zinc Dust Pigmented Primer, Performance-Based 1. Scope

3. Referenced Standards

1.1 This specification covers highly pigmented primers that contain zinc dust as the major pigment component (minimum 65% by weight in the dry film) and are defined by their ability to protect ferrous substrates. Individual products meeting minimum performance requirements of this standard may vary in formulation, raw materials, and application characteristics. SSPC-Paint 20 is a performance standard for inorganic or organic zinc-rich coatings that includes options for specifying higher zinc loading levels in the dry coating film.

3.1 The latest issue, revision, or amendment of the referenced documents in effect on the date of invitation to bid shall govern unless otherwise specified. Those documents marked with an asterisk (*) are referenced only in the Notes or the Appendix, which are not requirements of this specification.

1.2 This specification does not cover weldable preconstruction primers such as SSPC-Paint 30.

3.3 SSPC STANDARDS AND JOINT STANDARDS:

3.2 If there is a conflict between the requirements of any of the cited referenced documents and this specification, the requirements of this specification shall prevail.

SSPC-Guide 13

Guide for the Identification and Use of Industrial Coating Material in Computerized Product Databases SSPC-PA 2 Procedure for Determining Compliance with Coating Thickness Requirements SSPC-PA 15 Material and Preparation Require­ments for Steel Test Panels Used to Evaluate the Performance of Industrial Coatings SSPC-PA 16 Method for Evaluating Scribe Undercutting on Coated Steel Test Panels Following Corrosion Testing * SSPC-Paint 20 Zinc-Rich Coating, Type I – Inorganic and Type II ­– Organic * SSPC-Paint 30 Weld-Through Inorganic Zinc Primer SSPC-PS Guide 12.00 Guide to Zinc-Rich Coating Systems SSPC-SP 1 Solvent Cleaning SSPC-SP 5/NACE No. 1 White Metal Blast Cleaning SSPC-VIS 2 Guide and Visual Reference Photographs for Evaluating Degree of Rusting on Painted Steel Surfaces

1.3 This coating is intended for application by spray for use by itself or as a primer in a multi-coat system.

2. Description 2.1 Zinc-rich coatings, both topcoated and untopcoated, have been used successfully in a wide variety of environmental zones. For a detailed breakdown of applicability of various types of zinc-rich coatings in different environmental zones, refer to Table 1 of SSPC-PS Guide 12.00. Consult the coating manufacturer for specific exposure recommendations (see Note 12.1). 2.2 Zinc-rich coatings are classified by vehicle type as follows: Type IA Inorganic – post-cured, water-borne, alkali silicates Type IB Inorganic – self-cured, solvent-borne, alkyl silicates Type 1C Inorganic – self-cured, solvent-borne alkyl silicates Type IIA Organic - thermoplastic binders Type IIB Organic - thermoset binders SSPC PS 12.00 contains more information on the above classifications. 2.3 If no vehicle type is specified, either ­­Type I – Inorganic (IOZ), or Type II – Organic (OZ) is acceptable.

3.4 ASTM INTERNATIONAL STANDARDS:1

2.4 COMPONENTS: These zinc dust primers may consist of one, two, or three components.

ASTM D185 1

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Test Methods for Coarse Particles in Pigments, Pastes, and Paints

ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959. For referenced ASTM standards, visit the ASTM website, , or contact ASTM Customer Service at [email protected]. For Annual Book of ASTM Standards volume information, refer to the standard’s Document Summary page on the ASTM website.

SSPC-Paint 29 February 24, 2014 ASTM D520 ASTM D521 * ASTM D562 ASTM D714 ASTM D823

ASTM D1141 * ASTM D1475 * ASTM D1535 ASTM D1640 ASTM D1654 * ASTM D2369 * ASTM D2621 * ASTM D4541 ASTM D5894

4. Composition Requirements

Specification for Zinc Dust Pigment Test Methods for Chemical Analysis of Zinc Dust (Metallic Zinc Powder) Test Method for Consistency Measuring Krebs Unit (KU) Viscosity of Paints Using a Stormer-type Viscometer Test Method for Evaluating Degree of Blistering of Paints Standard Practices for Producing Films of Uniform Thickness of Paint, Varnish, and Related Products on Test Panels (Method D) Standard Practices for Substitute Ocean Water Test Method for Density of Liquid Coatings, Inks, and Related Products Practice for Specifying Color by the Munsell System Test Methods for Drying, Curing, or Film Formation of Organic Coatings at Room Temperature Test Method for Evaluation of Painted or Coated Specimens Subjected to Corrosive Environments Test Method for Volatile Content of Coatings Test Method for Infrared Identification of Vehicle Solids from Solvent-Reducible Paints Standard Method for Pull-Off Strength of Coatings Using Portable Adhesion Testers Standard Practice for Cyclic Salt Fog/UV Exposure of Painted Metal, (Alternating Exposures in a Fog/Dry Cabinet and a UV/Condensation Cabinet)

4.1 PIGMENTATION 4.1.1 The major pigment component in these coatings is zinc dust of the type described in ASTM D520 (see Note 12.3) and determined in accordance with ASTM D521. The paint shall contain a minimum of 65% zinc dust pigment by weight in the dry film. 4.1.2 Other pigment components may include extenders, curing aids, tinting colors, and suspension and pot-life control agents. 4.2 ANALYTICAL TEST DATA: If mutually agreed upon by purchaser and supplier, the coating manufacturer shall provide records of chemical and physical analysis of coating batches qualified by independent testing to meet this standard, including ASTM D520 Type, and percentage of metallic zinc loading (see Note 12.3).

5. Standard Testing Conditions 5.1 TEST PANELS: The hot rolled steel test panels shall conform to requirements of SSPC-PA 15, with the exception of SSPC-PA 15, Section 4.3 (Cure). Unless otherwise specified, the minimum cure time for organic zinc rich coatings prior to testing shall be 7 days, and the minimum cure time for inorganic zinc coatings shall be 30 days. 5.2 DRY FILM THICKNESS: The dry film thickness (DFT) of the coating on the test panels shall meet the manufacturer’s written recommended minimum and shall not exceed the manufacturer’s stated minimum by more than 25 micrometers (1 mil). The DFT shall be measured in accordance with Sections A5.3 through A5.5 of Appendix 5 of SSPC-PA 2.

6. Requirements of Liquid Coating The coating shall not have exceeded the manufacturer’s stated shelf life prior to testing.

3.5 AMERICAN ASSOCIATION OF STATE HIGHWAY AND TRANSPORTATION OFFICIALS (AASHTO) STANDARD:2 *AASHTO M300

6.1 MIXING: The liquid portion of a multi-component coating shall be mixed and dispersed to produce a product that is uniform, stable, free from grit, and in conformance with the requirements of this specification.

Inorganic Zinc Rich Primer

3.6 AMERICAN NATIONAL STANDARDS INSTITUTE (ANSI) STANDARDS:3

6.1.1 The pigment portion of a multi-component coating (if supplied as a dust) shall be dry and loosely packed prior to mixing.

ANSI/ASME B94.50 Basic Nomenclature and Definitions for Single-Point Cutting Tools 3.7 UNITED NATIONS STANDARD4

6.1.2 The ready-mixed coating shall be capable of being dispersed under mechanical agitation to a smooth, uniform consistency and shall not show any objectionable properties in the mix.

GHS Globally Harmonized System of Classification and Labelling of Chemicals (GHS), 4th Revised Edition. 2

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American Association of State Highway and Transportation Officials, 444 North Capitol Street, NW, Suite 249, Washington DC 20001, 202-624-5800. Standards are available online at American National Standards Institute, 1819 L Street, NW, Suite 600, Washington, DC 20036. Standards available online from United Nations Economic Commission for Europe, Transport Division, Palais des Nations, CH - 1211 Geneva 10, Switzerland. Copies of this standard may be obtained from the United Nations Publications Customer Service, National Book Network, 15200, 15200 NBN Way, Ridge Summit PA 17124 < https://unp.un.org>

6.1.3 After mixing, all types of coarse particles and skins as residue retained on a standard 60 mesh screen shall be no more than 0.5% by weight of the total coating, regardless of type, in accordance with ASTM D185. 2

SSPC-Paint 29 February 24, 2014 8.1.3.2 Type II: After the specified exposure time, the average scribe undercutting for Type II coatings shall be no greater than 3.2 mm (1/8 inch) as determined in accordance with SSPC-PA 16.

6.2 STORAGE LIFE: Neither the vehicle of the multicomponent coating nor the ready-mixed coating shall show thickening that is detrimental to performance or application properties. The components or coating shall exhibit no curdling, gelling, gassing, or hard caking after being stored unmixed for a minimum of six months from date of manufacture in a tightly sealed, unopened container at a temperature of 10 to 32°C (50 to 90°F).

8.2 ADHESION OF PRIMER FOLLOWING CYCLIC CORROSION/UV CABINET TESTING (TYPES I AND II): Unscribed portions of the triplicate test panels exposed as described in Section 8.1 shall be tested according to ASTM D4541 Method E using a Type V adhesion tester. Four pulls shall be performed on each panel. The minimum adhe­sion value of each pull shall be 4.1 MPa (600 psi) for both Type I and Type II coatings. A summary of adhesion requirements is provided in Table 2.

6.3 WORKING PROPERTIES: The mixed coating shall spray easily and show no signs of streaking, running, sagging, or other objectionable features when applied in accordance with the coating manufacturer’s product data sheet. The film should show no streaking, running, sagging, or other objectionable features when applied in accordance with ASTM D823, Method D, and dried in a vertical position.

10. Labeling

7. Laboratory Physical Tests of Applied Films

10.1 Labeling shall conform to ANSI Z129.1.

7.1 MUDCRACKING: The coating, when applied and aged in accordance with Sections 5.1, 5.2, and 5.4 to a 125 micrometer (5 mil) minimum dry film thickness, shall show no signs of mudcracking visible to the eye unaided by magnification.

10.2 Technical data shall be provided for at least all data elements categorized as “essential” in SSPC-Guide 13.

7.2 ADHESION OF CURED PRIMER: The coating, when applied, dried, and cured in accordance with Section 5, shall be tested as described in ASTM D 4541 Method E using a Type V adhesion tester. The test shall be performed on three panels using four pulls per panel. The minimum adhe­sion value of each pull shall be 4.1 MPa (600 psi).

11.1 While every precaution is taken to ensure that all information furnished in SSPC standards and specifications is as accurate, complete, and useful as possible, SSPC cannot assume responsibility nor incur any obligation resulting from the use of any materials, coatings, or methods specified herein, or of the specification or standard itself.

8. Accelerated Laboratory Weathering Tests

11.2 This specification does not attempt to address problems concerning safety associated with its use. The user of this specification, as well as the user of all products or practices described herein, is responsible for instituting appropriate health and safety practices and for ensuring compliance with all governmental regulations.

11. Disclaimer

8.1 CYCLIC CORROSION/UV EXPOSURE TEST: Triplicate panels prepared in accordance with Section 5 shall be exposed in a cyclic corrosion/UV test cabinet in accordance with ASTM D 5894. Both Type I and Type II coatings shall be exposed for 5040 hours. A summary of corrosion testing requirements is provided in Table 1.

12. Notes Notes are not requirements of this standard.

8.1.1 Rust Evaluation (Types I and II): After the specified exposure time, each replicate panel shall have no rusting of the coated portion. Slight rusting in the scribe mark is permissible and resulting staining should be ignored. Strips 6 mm (1/4 inch) wide along the edges of the panel may be ignored.

12.1 USES: This primer covers a range of vehicle types (inorganic/organic, water-borne/solvent-borne, one-pack/twopack/three-pack, chemical curing/thermoplastic). A detailed description of environmental zone conditions is contained in “About SSPC Standards and Guides,” available as a free download from SSPC.5 Consult SSPC-PS Guide 12.00 and coating manufacturers for specific uses and exposure limitations. PS Guide 12.00 does not address zinc dust loading. Caution should be used when zinc-rich coatings contact austenitic stainless steel. In case of fire, molten zinc metal may cause embrittlement of austenitic stainless steel.

8.1.2 Blister Evaluation (Types I and II): After the specified exposure time, there shall be no blistering of the coated portion. 8.1.3 Scribe Evaluation Requirements 8.1.3.1 Type I: After the specified exposure time, the average scribe undercutting for Type I coatings shall be no greater than 1.6 mm (1/16 inch) as determined in accordance with SSPC-PA 16.

12.2 VOC CONTENT: Federal limits for VOCs in industrial maintenance coatings were published in 1998 and may 5

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URL address is

SSPC-Paint 29 February 24, 2014

TABLE 1 SUMMARY OF CORROSION TESTING REQUIREMENTS Coating Type

Number of Specimens

Exposure Type

Time

Rust Rating, SSPC-VIS 2/ ASTM D610

Blister Rating, ASTM D714

Average Scribe Undercutting, SSPC-PA 16*

Type I (IOZ)

3

Accelerated (ASTM D 5894)

5040 Hours

All 10 (no blistering)

All 10 (no blistering)

maximum 1.6 mm (1/16 inch)

Type II (OZ)

3

Accelerated (ASTM D 5894)

All 10 (no blistering)

All 10 (no blistering)

5040 Hours

maximum 3.2 mm (1/8 inch)

* Note that due to the cathodic protection of scribe by zinc primers, scribes may be difficult to see.

TABLE 2 SUMMARY OF ADHESION TESTING REQUIREMENTS

Cured Panels (prior to D5894 exposure)

Number of Specimens

Coating Type

Cure Time

3

Type I (IOZ)

30 days minimum

3

Type II (OZ)

7 days minimum

Adhesion, Types I and II (ASTM D 4541, Method E, Type V tester) Minimum Value 4.1 MPa (600 psi) for each of 4 pulls

Accelerated Exposure Time Exposed Panels (after D5894 exposure)

3

Type I (IOZ)

3

Type II (OZ)

ASTM D 5894 5040 hours

4.1 MPa (600 psi) for each of 4 pulls

12.5 QUALITY ASSURANCE TESTS: If the user chooses, tests may be used to determine the acceptability of a lot or batch of a qualified coating. The quality assurance tests are used to determine whether the supplied products are of the same type and quality as those originally tested and certified for acceptance. The selected tests should accurately and rapidly measure the physical and chemical characteristics of the coating necessary to verify that the supplied material is substantially the same as the previously accepted material. All of the quality assurance tests must be performed on the originally submitted qualification sample. The results of these tests are used to establish pass/fail criteria for quality assurance testing of supplied products.

be found at http://www.epa.gov. These limits apply to the coating at the time of application after thinning according to the manufacturer’s recommendations. Many state and local governments and/or air quality management areas have more stringent VOC regulations than those in the federal rule. Information on the VOC content of each container before mixing or thinning is found on the container label and in the manufacturer’s safety data sheet. The coating manufacturer’s product data sheet usually provides information on the total VOC content of a coating after mixing and any recommended thinning. 12.3 Zinc dust is known to contain varying amounts of heavy metals that may pose worker exposure hazards. Applicable regulations to ensure worker and environmental protection should be followed.

12.5.1 Establishing Quality Assurance Acceptance Criteria: Many ASTM test methods contain precision and bias statements. Specification developers should be cognizant of the fact that these statements exist. Quality assurance test criteria should not be more stringent than the interlaboratory precision of the test methods used.

12.4 SOURCES FOR OTHER TESTS: Standard tests that may be useful for further qualification are available from a number of organizations, including ASTM, U.S. Government Federal and Military Specifications (TT-P; MIL-P, etc.), Federal Test Method Standards (141), and the Canadian Government Specifications Board. However, it should be emphasized that a well-designed non-standard test may often provide more meaningful information for a given service condition than one or more standard tests. Some supplementary performance tests are described in the Appendix.

12.5.2 Recommended Quality Assurance Tests: Recommended quality assurance tests include but are not limited to, infrared analysis (ASTM D 2621), viscosity (ASTM D 562), weight per gallon (ASTM D 1475), total solids (ASTM D 2369), dry time (ASTM D 1640), percent pigment (ASTM D 2371), and color (ASTM D 1535). 4

SSPC-Paint 29 February 24, 2014

13. Disclaimer

after the tape is removed must be cleaned from the panel with mineral spirits or other suitable methods that will not damage the test coating. Coat and seal all edges and the back side of each panel with a coating or tape that will provide the necessary protection to these surfaces. Once the zinc dust primer has cured for a minimum of two weeks, the panels are placed in a one-liter (one-quart) jar, which is filled with a 5% sodium chloride solution. The water is changed weekly.

13.1 This is a consensus standard developed by SSPC: The Society for Protective Coatings. While every precaution is taken to ensure that all information furnished in SSPC standards and specifications is as accurate, complete, and useful as possible, SSPC cannot assume responsibility nor incur any obligation resulting from the use of any materials, coatings, or methods specified herein, or of the specification or standard itself.

A1.3 Rating and Evaluation Criteria: The time at which visible rust first appears anywhere on the panel is recorded. A coating will have passed the bullet hole test if none of the replicate panels exhibits visible rust within 21 days for an inorganic zinc primer or within 14 days for an organic zinc primer.

13.2 This standard does not attempt to address problems concerning safety associated with its use. The user of this standard, as well as the user of all products or practices described herein, is responsible for instituting appropriate health and safety practices and for ensuring compliance with all governmental regulations.

A1.4 Additional Notes: Experimental results on bullet hole testing of various zinc-rich coatings are given in SSPC Report 87-02, “Level of Zinc Required in Zinc-Rich Paints.” A similar bullet hole immersion test is described in AASHTO M300.

NONMANDATORY APPENDIX A: SUPPLEMENTARY PERFORMANCE TESTS

A2 FUEL AND SALT WATER IMMERSION

While not required to meet the requirements of this specification, the following or other performance tests may be valuable to the purchaser because of the diversity of possible service environments in which these primers may be used. Agreement between contracting parties as to these tests and results must be established before issuing procurement documents.

A2.1 Significance of Test: Inorganic zinc-rich coatings have been used in ballast tanks, which are alternately exposed to petroleum fuel and seawater ballast. A2.2 Description of Test: A test developed by the U.S. Navy calls for immersion of two blast cleaned and coated panels in the following cycle: one week in 3% salt water; one week in aromatic synthetic gasoline; and two hours in hot (80°C, 176°F) synthetic sea water (to simulate cleaning conditions). Details for making synthetic seawater are furnished in ASTM D 1141.

A1 BULLET HOLE TEST A1.1 Significance of Test: This test is intended to evaluate the ability of a primer to sacrifice itself and cathodically protect adjacent areas of bare steel. A1.2 Description of Test: Test panels shall be triplicate flat mild steel plates, 75 x 150 x 1.6 mm (3 x 6 x 1/16 inches), blast cleaned to SSPC-SP 5. A magnet, tape, or other suitable method is to be used to mask a 3.8 cm (1.5 inch) diameter circle in the center of the panel. Coating shall be applied according to the manufacturer’s specifications, including recommended dry film thickness. If masking tape is used, any residue remaining

A2.3 Evaluation Criteria: After 20 cycles, coatings are required to exhibit no pinpoint rusting, no loss of adhesion, no blisters larger than 1.5 millimeters (1/16 inch) in diameter, and no more than 3% of the surface covered with rust and/or blisters.

Copyright © SSPC standards, guides, and technical reports are copyrighted world-wide by SSPC: The Society for Protective Coatings. Any photocopying, re-selling, or redistribution of these standards, guides, and technical reports by printed, electronic, or any other means is strictly prohibited without the express written consent of SSPC: The Society of Protective Coatings and a formal licensing agreement.

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