The reason we prepare a surface prior to painting is not well understood. We do it because we think we’re supposed to do it … but why? According to The Society for Protective Coatings (SSPC) Surface Preparation Commentary (SSPC-COM), we prepare a surface “to remove surface contaminants that can induce premature coating failure” and “to provide a clean surface with adequate profile for good coating adhesion”. But after surface preparation is completed how do you know if it is sufficient? If it meets the Standard or the spec? If it’s “good enough”?
Regarding cleanliness, The Society for Protective Coatings (SSPC) publishes Visual Standards that are high quality photographic references. If verification of surface preparation using SSPC Visual Standards is important to you, include it in your specification. Thereafter, use these Visual Standards to help determine if the surface preparation achieved is adequate.
There are four Visual Standards used when verifiying steel surface preparation : Vis 1 (for Steel Surfaces Prepared by Abrasive Blast Cleaning), Vis 3 (for Steel Surfaces Prepared by Power- and Hand-Tool Cleaned Steel), Vis 4 (for Steel Surfaces Prepared by Water Jetting), and Vis 5 (for Steel Surfaces prepared by Wet Abrasive Blast Cleaning).
Does referencing surface preparation Standards (outlined in a previous post) in your specification guarantee that your clients will receive the surface preparation for which they paid? Yes … if, that is, verification of these surface preparation is made with Visual Standards. It’s very easy to do, and they’re very easy to use.
After a surface is prepared for painting, the photographic Visual Standard is simply placed on the surface(s) prepared. If the surface matches the visual image, the surface may be considered “done” and priming and painting may begin. If the prepared surface does not match the visual image, more work may be required. Using Visual Standards for verfiying surface preparation minimizes jobsite arguments that can stall a project’s progress.
Want to know more about Visual Standards?