Packing Group
For packing purposes, substances other than those of classes 1, 2, 5.2, 6.2 and 7, and other than self-reactive substances of class 4.1 are assigned to packing groups in accordance with the degree of danger they present:
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More on performance categories
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Labeling letter is found on the packaging
Stronger packagings (high performance) shall be used for substances presenting a high danger (PG I).
X packaging -> for packaging groups I, II and III
Y packaging -> for packaging groups II and III
Z packaging -> for packaging groups III
Stronger packagings (high performance) shall be used for substances presenting a high danger (PG I).
X packaging -> for packaging groups I, II and III
Y packaging -> for packaging groups II and III
Z packaging -> for packaging groups III