1.1 ,This practice covers the procedure for locating, by the use of a solution of copper sulfate, the thinnest spot in a zinc coating (hot dipped, electroplated, or sprayed) on iron or steel articles that are coated after the shape is produced by casting, drawing, pressing, or other forming methods. Examples are: electrical metallic tubing and rigid conduit pipe, castings and forgings, and structural steel, on special hardware, such as poleline, builder',s, and farm implement hardware, bolts, nuts, screws, and other miscellaneous general hardware.