Dunnage

Dunnage comprises timber planks, bamboo mats, paper sheets, rubber pads, airbags, or other material placed under, around, or between cargo units in a ship's hold to protect the cargo from moisture and damage, to distribute weight, to prevent cargo from shifting, and to ensure adequate air circulation around moisture-sensitive commodities. The choice and placement of dunnage is addressed in SOLAS Chapter VI and detailed in the CTU Code (Code of Practice for Packing of Cargo Transport Units) and in port-specific guidance for break-bulk operations. The chief mate plans dunnage requirements at the cargo planning stage, considering the stowage factor, the nature of the commodity, the expected weather, and the voyage duration. Timber dunnage placed beneath bags of grain or fertiliser absorbs condensation and prevents moisture damage; rubber anti-slip mats under heavy project cargo prevent sliding on polished steel decks. Inadequate dunnage in a grain cargo can allow the surface of the grain to shift, reducing stability—a scenario directly addressed by the International Grain Code (Grain Code), which requires dunnage in unlevel surfaces and longitudinal divisions in filled compartments. The OOW records dunnage placement in the cargo survey report before signing the mate's receipt.