The data in this document is, at this stage, primarily concerned with the interface of pallet/container loaders and lower-deck compartments of standard and wide-body aircraft although the principles illustrated may be applied to the main-decks of narrow and wide-body aircraft. NOTE: For the purpose of this document, in accordance with Part 3 of the Directives for the technical work of ISO and with accepted IATA practice, minimum essential criteria defined by the word "shall" are absolute requirements. Recommended criteria identified by the word "should", while considered important, are not mandatory.