What system is used to gauge black iron, galvanized iron, and stainless steel?

• A. U.S. Standard gauge
• B. Metric gauge
• C. Decimal inch gauge
• D. British gauge

Answer: (A)

Thickness for these ferrous metals is described using the U.S. Standard gauge system. This system assigns a gauge number to a sheet’s thickness, with higher numbers meaning thinner metal, and the exact thickness for a given gauge is defined in a material-specific gauge chart. It’s the standard reference used in many U.S. shops for black iron, galvanized iron, and stainless steel, as opposed to metric gauge, decimal inch gauge, or British gauge.