BS EN 13523-4:2014 Coil coated metals - Test methods Part 4: Pencil hardness

This part of EN 13523 describes the procedure to assess the relative hardness of an organic coating on a metallic substrate, by means of pencils of known hardness.
Smooth surfaces will give more accurate results but the method is also applicable for textured surfaces. The more pronounced the texture, the greater the unreliability of results.