The stowage factor of cargo is a quick reference to evaluate the efficiency of the use of ship space and a tool to project fuel expenditures. The stowage factor is also a tool for shipping managers to quickly grasp the overall impact of shipments by converting provided information from volume to cargo weight or weight to volume based on cargo priority.
Measure the actual volume of the cargo to be shipped. If the shipment is containerised, refer to the cubic volume listed by the container provider for this measurement. If the cargo is not containerised, multiple the length by width by height of the cargo and any empty space allocated for the cargo to determine the volume.
Measure and obtain the actual weight of the cargo and its packaging. If available, place cargo on an appropriately sized scale. This measurement can also be done by comparing the weight of the container/rail car/pallet before the cargo is loaded and after the cargo is loaded.
Divide the cubic measure of the cargo by the actual weight of the cargo. Ensure that calculation units (cubic inch, feet, meter, pound, kilogram, metric ton, etc.) are labelled in the calculation notes and communications.
Review available records for pending shipments to ensure data consistency to prevent issues regarding measuring units used (e.g. cubic meters per ton or kilogram). Also, confirm that cargo descriptions are consistent with the information provided. For example, uncompressed cotton will have a higher stowage factor then a shipment of compressed cotton. Review previous shipments or stowage factor guides to further validate pending shipments.
Stowage Factor is an evaluation for the overall utilisation of cargo space but should be considered independent of the overall cargo capacity of a ship. Ship stowage is based on calculating the optimal centre of balance for the ship and packaging, not the average storage factor available in the vehicle.