What is the limit of staining for SSPC-SP10/NACE 2 per each unit area?

The correct answer is 5%. SSPC-SP10/NACE 2 is a standard that focuses on the surface preparation of steel prior to the application of protective coatings. One of its key requirements is the stipulation on cleanliness levels, specifically regarding the allowed amount of staining.

According to the standards, the maximum limit of staining permissible for areas prepared under SSPC-SP10/NACE 2 is defined as 5% of the unit area. This high standard of cleanliness is crucial because it ensures that the surface is adequately prepared to promote adhesion of the coating, ultimately leading to better performance and longevity of the coating system.

By adhering to the 5% staining limit, the inspector can affirm that the surface is largely free of contaminants like rust, mill scale, or any other surface imperfections that could hinder the effectiveness of the coating. This emphasizes the importance of rigorous surface preparation in corrosion control efforts.