Triple Packaging

The primary receptacle holds the material. The secondary packaging contains any leak from the primary, and for liquids carries absorbent material sufficient to take the entire contents. The outer packaging protects the assembly in handling and carries the marks, labels and documentation.

The same three layers appear at every level of the regime, but the performance requirement differs sharply. PI 650 for UN3373 requires a 1.2 metre drop. PI 620 for UN2814 and UN2900 requires UN-certified packaging tested to 9 metres with a puncture test. An exempt specimen requires three layers that will not leak, without a performance test. Which of the three applies is settled by the determination, not by the packaging catalogue.