Applying Three-Coat Latex Painting System
PAINTING SYSTEM NO. 18.01 – Three-Coat Latex Painting System
1.1 This speciﬁcation covers a complete latex painting system for structural steel.
1.2 This painting system is suitable for use on parts or structures exposed in Environmental Zones 1A (interior, normally dry), and 1B (exterior, normally dry), and high humidity or mild chemical atmospheres.
1.3 The ﬁnish paint is semi-gloss, chalk resistant, and allows for a choice of colors.
2.1 This painting system consists of surface preparation by commercial blast, two coats of latex primer, and one latex semi-gloss ﬁnish coat.
3. Referenced Standards
3.1 The latest issue, revision, or amendment of the referenced standards in effect on the date of invitation to bid shall govern, unless otherwise speciﬁed.
3.2 If there is a conﬂict between the requirements of any of the cited referenced standards and this speciﬁcation, the requirements of this speciﬁcation shall prevail.
3.3 SSPC STANDARDS AND JOINT STANDARDS:
PA 1 Shop, Field, and Maintenance Painting of Steel
PA 2 Measurement of Dry Coating Thickness With Magnetic Gages
PA Guide 4 Guide to Maintenance Repainting with Oil Base
Paint 23 Latex Primer for Steel Surfaces
Paint 24 Latex Semigloss Exterior Topcoat
SP 5/NACE No. 1 White Metal Blast Cleaning
SP 6/NACE No. 3 Commercial Blast Cleaning
SP 8 Pickling
SP 10/NACE No. 2 Near-White Blast Cleaning
3.4 AMERICAN SOCIETY FOR TESTING AND MATERIALS (ASTM) STANDARDS:
D 3925 Standard Practice for Sampling Liquid Paints and Related Pigmented Coatings
4. Surface Preparation
4.1 SSPC-SP 6, “Commercial Blast Cleaning,” or SSPCSP 8, “Pickling.” If speciﬁed in the procurement documents, a better degree of cleaning shall be substituted (SSPC-SP 5, “White Metal Blast Cleaning,” or SSPC-SP 10, “Near-White Blast Cleaning”).
5.1 PRIMER: SSPC-Paint 23, “Latex Primer for Steel Surfaces.”
5.2 INTERMEDIATE: SSPC-Paint 23, “Latex Primer for Steel Surfaces,” tinted to a color contrasting with the primer and the ﬁnish coat.
5.3 FINISH COAT: SSPC-Paint 24, “Latex Semi-Gloss Exterior Topcoat.” The color must be speciﬁed.
6. Paint Application
6.1 PAINT APPLICATION: Follow the requirements SSPCPA 1, “Shop, Field, and Maintenance Painting of Steel.”
6.2 TOUCH-UP PAINTING: In accordance with speciﬁcation SSPC-PA 1, “Shop, Field, and Maintenance Painting of Steel” and in particular with the section thereof entitled “Field Painting.”
6.3 MAINTENANCE PAINTING: For maintenance painting procedures, see SSPC-PA Guide 4, “Guide to Maintenance Repainting with Oil Base or Alkyd Painting Systems.”
6.4 NUMBER OF COATS: Minimum of three.
6.5 DRY FILM THICKNESS OF PAINT SYSTEM: Not less than the following as measured in accordance with SSPCPA 2, “Measurement of Dry Coating Thickness with
Magnetic Gages”: primer 64 micrometers (2.5 mils); intermediate coat 50 micrometers (2.0 mils); ﬁnish coat 38 micrometers (1.5 mils); for the three-coat painting system 150 micrometers (6.0 mils).
7.1 All work and materials supplied under this speciﬁcation are subject to timely inspection by the purchaser or his authorized representative. The contractor shall correct such work or replace such material as is found defective under this speciﬁcation (See Note 9.1.). In case of dispute, unless otherwise speciﬁed, the arbitration or settlement procedure established in the procurement documents shall be followed. If no arbitration or settlement procedure is established, then a procedure mutually agreeable to purchaser, material supplier, and contractor shall be used.
7.2 Samples of paints under this painting system may be requested by the purchaser and shall be supplied upon request along with the manufacturerʼs name and identiﬁcation for the materials. Samples may be requested at the time the purchase order is placed, or may be taken from unopened containers at the job site.
7.3 Unless otherwise speciﬁed, the sampling shall be in accordance with ASTM D 3925.
8.1 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 speciﬁ ed herein, or of the speciﬁcation or standard itself.
8.2 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 insuring compliance with all governmental regulations.
Notes are not a requirement of this speciﬁcation.
9.1 The procurement documents should establish the responsibility for samples, testing, and any required afﬁdavit certifying full compliance with the speciﬁcation.
9.2 It is not recommended to expose steel to the weather with less than two coats of water borne coating. Therefore, the intermediate coat should be applied before any exposure and the ﬁnish coat within three months for maximum performance of this painting system.