surface cleanliness
In addition to being brushed or abraded during the initial surface preparation stage, the coated surface may also be sprayed, high-pressure water sprayed or simply rinsed. Many times, wear media or water is recycled. At this point it is important to carefully monitor the contamination levels of the recycled material to avoid re-contamination of the surfaces being cleaned.
Surface contamination from salts such as chlorides, sulfates, nitrates, etc. can cause peeling, blistering and premature coating anomalies. Therefore, in multi-coat systems it is necessary to measure the cleanliness of the surface prior to application to ensure that the substrate or coated surface is free of contamination before the next coat is applied.
There are a variety of field testing methods to ensure surface cleanliness:
Dust Test Kit
Chloride Ion Specific Test Kit, Tests Abrasives and Water
Chloride-specific test kit to test surface cleanliness
Soluble Salt Test Kit - Using the Bresle Patch Method
Soluble Salt Test - Using a Salt Contamination Meter
Surface Contamination Test Kit
*Measurement of chloride, sulfate and nitrate levels
*Test pH, iron, chloride and soluble salt levels
Visual inspection of the surface is also required, and there are various graphical standards to assist operators and inspectors.
