Twenty-foot Equivalent Unit

A Twenty-foot Equivalent Unit (TEU) is the standard unit of measurement for container ship capacity and cargo throughput, representing the volume occupied by one ISO 20-foot shipping container (approximately 6.1 m long × 2.44 m wide × 2.59 m tall) as defined in ISO 668. A 40-foot container (FEU) equals two TEU. Ship capacity is expressed in TEU; terminal throughput is measured in TEU per year; and global trade volumes are tracked in millions of TEU. The standardisation of the corner casting geometry to ISO 1161 allows containers to be stacked and secured interchangeably on any vessel and at any terminal worldwide. For the chief mate, TEU counts feed directly into the loading computer for stability and stress calculations. The bay plan divides the vessel into numbered bays, rows, and tiers, and each slot is identified by a unique bay-row-tier number; the BAPLIE electronic stowage plan maps every container to its slot, weight, and class. Container weights must be declared and verified under SOLAS Chapter VI, Regulation 2 (the Verified Gross Mass rule) before loading, as undeclared overweight containers have destabilised vessels and collapsed container stacks. The OOW should be familiar with the ship's maximum stack weight limits and the distribution of heavy containers to ensure the loading plan complies.