As mentioned, the most analyzed element in the inspection of hot-dip galvanized steel is the coating thickness. However, there are a number of other inspection tests performed on galvanized steel to verify compliance with the standards ASTM A123/A123M, A153/A153M, or A767/A767M.

The inspections performed on all coatings are:

• Coating Thickness/Coating Weight - magnetic gauges, optical microscopy, weigh-galvanize-weigh, and weigh-strip-weigh
• Finish and Appearance - visual inspection

There are also a number of additional tests that can be performed but are only done when there is a concern or question. These tests include:

• Adherence - stout knife
• Embrittlement - similar bend radius, sharp blow, and steel angle
• Passivation agent
• Bending - minimum finished bend diameter table

The rest of this section will provide more detail on the inspection of hot-dip galvanizing and how to perform these tests. However, to fully understand how to inspect galvanized steel and comprehend what the specifications require, including what is acceptable and rejectable, take the Inspection Course.