Which option matches the Metal Box Category with steel boxes?

• A. 3A2
• B. 4A
• C. 1H1
• D. 3H1

Answer: (B)

The key idea is that IATA DGR packaging codes use a number to indicate the packaging material type and a letter to specify the exact material/construction. For metal boxes, the number is 4 and the letter A denotes steel construction, so the category that matches a steel box is 4A. This is the best choice because it directly encodes both the metal nature and the steel build of the box. The other codes correspond to different materials or container types, so they don’t represent a steel box. In practice, 4A identifies a steel box and its required testing and compliance for safe transport.