Packaging: Authorization, UN Specification Marks, Closures, and Inspection
Packaging is the selection-and-condition domain. The exam tests whether you can choose packaging authorized for the material and packing group, read UN specification marks, follow closure and filling rules, and reject damaged packaging.
Authorized packaging
The Hazardous Materials Table entry for a material lists authorized packagings in its packaging columns: exceptions, non-bulk, and bulk. You must use a packaging authorized for that material and for its packing group. The UN specification mark on a package tells you the packaging type and performance level. In a mark such as "4G/Y15/S/...", "4G" is a fiberboard box, "Y" is the performance level for Packing Group II and III, and "15" is the maximum gross mass in kilograms. "X" is the highest performance level (Packing Group I, II, or III), "Y" covers Packing Group II and III, and "Z" covers Packing Group III only. A Packing Group II material therefore may not be shipped in a "Z" package.
Closures and filling
Closures must be tightened according to the packaging manufacturer's closure instructions. A package must not leak, and liquid packagings must not be filled completely; leave enough outage for expansion so the package does not distort or leak at elevated temperature. Do not overfill, and do not use a packaging for a material that is incompatible with its construction.
Inspection and securement
Before loading, inspect each package for cuts, stains, leaks, weak closures, and damaged fittings. Reject damaged packaging. Check cylinder requalification dates and cargo tank test dates when applicable. Secure packages so they cannot shift, and keep them upright if orientation arrows require it.
Worked example
A shipper offers 400 lb of "UN1789, Hydrochloric acid, 8, PG II" in a fiberboard box marked "4G/Z22/S/...". The "Z" performance level is only for Packing Group III, so it is not authorized for a Packing Group II material. The shipper needs a box with a "Y" or "X" mark, or another packaging authorized by the Hazardous Materials Table for that material and packing group, and must follow the closure instructions.
Traps
Do not assume any UN-marked package is acceptable; the performance level and the Table entry both matter. Do not ignore closure instructions, overfill liquids, or reuse damaged packaging. Do not load a corrosive into an incompatible container, and do not forget cylinder or cargo tank inspection dates.