Soluble Salt Testing Frequency and Locations on Previously Coated Surfaces

This standard establishes siting and frequency requirements for soluble salt testing before application of a subsequent coating system to previously coated substrates and replacement substrate material. It does not include allowable limits of soluble salts, which are typically addressed by the procurement documents or the coating manufacturer’s documentation.

SSPC-Guide 24 addresses the siting and number of soluble salt tests on uncoated or shop-coated steel surfaces. See Paragraph A1 of Appendix A (nonmandatory) for additional information about Guide 24.

The standard was originally issued in January 2016 to provide assistance when specifying or performing soluble salt testing on previously coated substrates. It provides requirements for all parties in an effort to increase consistency and reduce subjective interpretation. This revision updates the standard to reflect current testing practices.