ISO 668
ISO 668 - Series 1 freight containers — Classification, dimensions and ratings is an ISO international standard which classifies intermodal freight shipping containers and standardises their size and weight specifications. Introduced in 1968, ISO 668 regulates both external and internal dimensions of containers, as well as the minimum door opening size, where applicable. It also specifies the associated gross weight ratings, and requirements for load transfer areas in the base structures of containers, since amendment 1 of 2005.
The current version of the standard is the Seventh edition, which integrates version E.
