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SSPC-SP 6/NACE No. 3
<br />January 1, 2007
<br />oxides, corrosion products, and other foreign matter from ali
<br />surtaces and allows stains to remain on 33 percent of each
<br />unit area of surface, while industrial blast cleaning allows
<br />defined mill scale, coating, and rust to remain on less than 10
<br />percent of each unit area of surface and allows defined stains
<br />to remain on all surtaces.
<br />This joint standard was originally prepared in 1994 and
<br />reaffirmed in 2000 bythe SSPC/NACETaskGroupAon Surface
<br />Preparation by Abrasive Blast Cleaning. This joint task group
<br />includes members of both the SSPC Surface Preparation
<br />Committee and the NACE Unit Committee T-6G on Surface
<br />Preparation. It was reaffirmed in 2006 by the SSPC Surtace
<br />Preparation Committee and NACE Specific Technology
<br />Group (STG) 04, Protective Coatings and Linings: Surface
<br />Preparation.
<br />In SSPC/NACE standards, shall and must are used
<br />to state mandatory requirements. Shou/d is used to state
<br />that which is considered good and is recommended but is
<br />not absolutely mandatory. May is used to state that which is
<br />considered optional.
<br />Section 1: General
<br />1.1 This joint standard covers the requirements for
<br />commercial blast cleaning of uncoated or coated steei surfaces
<br />by the use of abrasives. These requirements include the end
<br />condition of the surface and materials and procedures neces-
<br />sary to achieve and verify the end condition.
<br />1.2 The mandatory requirements are described in
<br />Sections 1 to 9. Section 10, "Comments," and Appendix A,
<br />"Explanatory Notes," are not mandatory requirements of this
<br />standard.
<br />1.3 Information about the function of commercial blast
<br />cleaning is in Paragraph A1 of Appendix A.
<br />1.4 Information about use of this standard in maintenance
<br />coating work is in Paragraph A2 of Appendix A.
<br />Section 2: Definitions
<br />2.1 Commercial Blast Cleaned Surtace: Acommercial
<br />blast cteaned surface, when viewed without magnification, shall
<br />be free of all visible oil, grease, dust, dirt, mill scale, rust, coating,
<br />oxides, corrosion products, and other foreign matter. Random
<br />staining shall be limited to no more than 33 percent of each
<br />unit area of surface (approximately 5,800 mmz [9.0 in.2]) (i.e.,
<br />a square 76 mm x 76 mm [3.0 in. x 3.0 in.]) and may consist
<br />of light shadows, slight streaks, or minor discolorations caused
<br />by stains of rust, stains of mill scale, or stains of previously
<br />applied coating.
<br />2.1.1 Acceptable variations in appearance that do not
<br />affect surface cleaniiness as defined in Paragraph 2.1 include
<br />variations caused by type of steel, originai surface condition,
<br />thickness of the steel, weld metal, mill or fabrication marks,
<br />heat treating, heat-affected zones, blasting abrasives, and
<br />differences because of blasting technique.
<br />2.1.2 SSPC-VIS 13 may be specified to supplement the
<br />written definition. In any dispute, the written definition set
<br />forth in this standard shall take precedence over reference
<br />photographs and comparators. Additional information on
<br />reference photographs and comparators is in Paragraph A3
<br />of Appendix A.
<br />Section 3: Associated Documents
<br />3.1 The latest issue, revision, or amendment of the docu-
<br />ments listed in Paragraph 3.3 in effect on the date of invitation
<br />to bid shall govern unless otherwise specified.
<br />3.2 If there is a conflict between the requirements of any
<br />of the documents listed in Paragraph 3.3 and this standard,
<br />the requirements of this standard shall prevail.
<br />3.3 Documents cited in the mandatory sections of this
<br />standard include:
<br />Document
<br />Title
<br />SSPC-AB 1'
<br />Mineral and Slag Abrasives
<br />SSPC-AB 25
<br />Cleanliness of Recycled Ferrous
<br />Metallic Abrasives
<br />SSPC-AB 36
<br />Ferrous Metaliic Abrasives
<br />SSPC-SP 1'
<br />Solvent Cleaning
<br />SSPC-VIS 1
<br />Guide and Reference Photographs
<br />for Steel Surfaces Prepared by Dry
<br />Abrasive Blast Cleaning
<br />Section 4: Procedures Before Cleaning
<br />4.1 Before blast cleaning, visible deposits of oil, grease,
<br />or other contaminants shall be removed in accordance with
<br />SSPC-SP 1 or other agreed-upon methods.
<br />4.2 Before blast cleaning, surface imperfections such as
<br />sharp fins, sharp edges, weld spatter, or burning slag should
<br />be removed from the surface to the extent required by the
<br />procurement documents (project specification). Additional
<br />information on surface imperfections is in Paragraph A4 of
<br />Appendix A.
<br />4.3 If reference photographs or comparators are specified
<br />to supplement the written standard, the condition of the steel
<br />priorto blast cleaning should be determined before the blasting
<br />commences. Additional information on reference photographs
<br />and comparators is in Paragraph A3 of Appendix A.
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