A.
As long as the overpack is strong enough to hold all the completed packages, any container can be used as an overpack whether it is a UN certified package or an eligible LTD QTY package. The United States in their state variation places emphasis on protection rather than convenience with overpacks which must be carefully noted. When using UN certified packaging as overpack, in order to avoid unnecessary misunderstanding, it is recommended that the UN package specification marking be covered with tape, although there is nothing wrong in using a UN certified package as an overpack. Needless to mention, segregation of certain dangerous goods which may react dangerously with each other must be observed.