Glossary—dunnage

GISTnet Glossary—dunnage

(dangerous goods) verb: To secure cargo within an outer packaging, overpack or cargo transport unit using non-reactive materials such as fiberboard, wood, or paper. Dunnage is often used interchangeably with dunnaging.

(general use) When used as a verb, "dunnage" refers to the task of placing lumber or other non-reactive material(s) under, around, between or over cargo stowed the hold of a vessel, rail car, truck, intermodal container, or other freight container, or around the contents within a cargo package or ULD, in order to:

Prevent excess minor movement of materials during transportation by filling voids within a conveyance, ULD or shipping package;
Maintain separation between packages and/or unpackaged items of cargo;
Distribute the weight of cargo with respect to floor and/or loading of cargo on top of other cargo;
Provide cargo ventilation air space and paths;
Provide an exit path for liquid spillage, rain or seawater, to prevent absorption of such liquids by cargo packaged stowed directly on the conveyance floor or deck;
Prevent metal-to-metal contact (i.e., electrical conductivity, corrosion or sparking); and,
Other cargo-specific protective and safety purposes.

Note: Dunnage is generally not used to secure cargo in place against major movement within a container. When this is required, some form of blocking, bracing and tie down is required, which requires much more planning, tie-down hardware and/or carpentry than dunnage placement.

When used as a noun, "dunnage" refers to the materials (also known as dunnaging) used to secure, support or separate items of cargo during transportation, but which does not remain associated with the cargo following transportation, and whose purpose is one of the above listed.

Dunnage typically consists of low grade lumber, plywood or other non-reactive material (i.e., material that will not react with or adversely affect cargo it is placed against), and is placed as needed during the cargo loading process.

Lumber is a widely used dunnaging material within transportation conveyances and within packaging of machinery and heavy equipment. But a variety of other materials, such as fiberboard, various types of foam, "bubble-pack" and even airbags may also be used within packages, ULD's and even freight containers. The important characteristics are that the material will accomplish the needed cargo protection and/or load distribution, and will not adversely affect the cargo or conveyance, and will not contaminate or otherwise increase risk to the shipment or conveyance, and is not restricted from use in transportation or entry into the commerce of any country or other legal jurisdiction through which the cargo or conveyance will pass.

Though they typically are used in combination, dunnage is distinguished from blocking, bracing and tie down in that the latter is carefully fastened together to operate as a structure, whereas dunnage is generally held in place by gravity, outer packaging and/or the cargo itself.

Dunnage is a transportation carrier or cargo terminal responsibility with respect to vessel stowage of most breakbulk cargo. Dunnage is a shipper responsibility when required within cargo packages, ULDs, and shipper-packed containers, trucks, rail cars and barges.

As a general rule, when dunnage is furnished by the shipper within a cargo package, ULD or shipper-packed container, it becomes part of the shipping weight and cubic measurement of the cargo, and will be assessed transportation charges as freighted. However, a carrier tariff or TLIs may provide an allowance for dunnage and/or may specifically exclude dunnage from the rate basis. (See tare weight allowance.) In such cases, a freight forwarder can be of great value in bringing this to the attention of the shipper and carrying the tare allowance or dunnage deduction over into the B/L instructions.

In general, dunnage used within a shipper-packed container or other conveyance should be documented on the transportation document for several reasons. First, it adds to the gross weight of the vehicle (GVW) and could possibly cause a load to exceed the maximum vehicle highway weight limit. Second, for containers going to a foreign destination, the use of wood dunnage becomes subject to destination phytosanitary requirements. Third, undocumented dunnage may add enough weight to a container to trigger a customs inspection and perhaps even a fine, based on a discrepancy between the stated cargo weight on the transportation document vs. the scale weight of the loaded container, less container tare weight.

Dunnage lumber used in international commerce must meet basic phytosanitary criteria, including being free of bark, and free of insect infestation. Some countries require dunnage lumber to be accompanied with a phytosanitary inspection certificate. A growing number of countries also require dunnage lumber to comply with ISPM-15 standards (i.e., be heat treated or fumigated, and have WPM marking). Refer to the GISTnet Country Guides and links therein for particular country requirements.

Dunnage arriving which does not destination country treatment and/or phytosanitary requirements will likely result in quarantine of the dunnage and associated cargo, adding considerable expense and delay to the movement of the cargo and the transportation conveyance!