There are standard format requirements for the packaging of dangerous goods, and each content corresponds to different meanings. For example, 1 is barrel, 3 is can, 4 is box, 5 is bag, a steel, H plastic, I II, III is several types of packaging, D indicates how many goods are packed in the Arabic numerals behind the closure, and there are national or laboratory codes, year, batch number and other information behind it. The package of dangerous goods must comply with the fixed format requirements, otherwise the declaration cannot be made at the time of export inspection, or the maritime safety administration and customs will also check the marks on the package at the time of import danger declaration.