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Cargo Securement Glossary

Aggregate working load limit — The summation of the working load limits or restraining capacity of all devices used to secure an article on a vehicle.

Anchor point — Part of the structure, fitting, or attachment on a vehicle or cargo to which a tiedown is attached.

Article of cargo — A unit of cargo, other than a liquid, gas, or aggregate that lacks physical structure (e.g. grain, gravel, etc.), including articles grouped together so that they can be handled as a single unit or unitized by wrapping, strapping, banding, or edge protection device(s).

Banding — A strip of material that may be used to unitize articles and is tensioned and clamped or crimped back upon itself (same as “Strapping”).

Bell pipe concrete — Pipe whose flanged end is of larger diameter than its barrel.

Binder — A device used to tension a tiedown or combination of tiedowns.

Blocking — A structure, device, or another substantial article placed against or around an article to prevent horizontal movement of the article.

Bolster — A transverse load bearing structural component, particularly a part of a log bunk.

Boulder — A large piece of natural rock that may be rounded if it has been exposed to weather and water, or is rough if it has been quarried.

Bracing — A structure, device, or another substantial article placed against an article to prevent it from tipping that may also prevent it from shifting.

Bulkhead — A vertical barrier across a vehicle to prevent forward movement of cargo.

Bundle — A group of articles that has been unitized for securement as a single article.

Bunk — A horizontal bolster fitted with a stake at each end that together supports and contains a stack of logs, and is installed transversely.

Cab shield — A vertical barrier placed directly behind the cab of a tractor to protect the cab in the event cargo should shift forward.

Cargo — All articles or material carried by a vehicle, including those used in operation of the vehicle.

Chock — A tapered or wedge-shaped piece used to secure round articles against rolling.

Cleat — A short piece of material, usually wood, nailed to the deck to reinforce blocking.

Coil bunk — A device that keeps timbers supporting a metal coil in place. Contained — Cargo is contained if it fills a sided vehicle, and every article is in contact with or sufficiently close to a wall or other articles so that it cannot shift or tip if those other articles are also unable to shift or tip.

Container chassis — A semitrailer of skeleton construction limited to a bottom frame, one or more axles, specially built and fitted with locking devices for the transport of cargo containers, so that when the chassis and container are assembled, the units serve the same function as an over-the-road trailer.

Container chassis vehicle — A vehicle especially built and fitted with locking devices for the transport of intermodal containers.

Cradle — A device or structure that holds a circular article to prevent it from rolling.

Crib-type log trailer — Means a trailer equipped with stakes, bunks, a front-end structure, and a rear structure to restrain logs. The stakes prevent movement of the logs from side to side on the vehicle while the front-end and rear structures prevent movement of the logs from front to back on the vehicle.

Crosswise — Same as “Lateral”.

Crown — The rounded profile of the top of a stack of logs, when viewed from the ends of the stack.

Cut-to-length logs — Included in shortwood.

Deck — The load carrying area (floor or bed) of a truck, trailer, or intermodal container.

Direct tiedown — A tiedown that is intended to provide direct resistance to potential shift of an article. One end of a direct tiedown is attached to the cargo itself.

Dunnage — All loose materials used to support and protect cargo.

Dunnage bag — An inflatable bag intended to fill otherwise empty space between articles of cargo, or between articles of cargo and the wall of the vehicle.

Edge protector — A device placed on the exposed edge of an article to distribute tiedown forces over a larger area of cargo than the tiedown itself, to protect the tiedown and/or cargo from damage, and to allow the tiedown to slide freely when being tensioned.

Eye (of a cylindrical object) — The hole through the center of the article.

Flatbed vehicle — A vehicle with a deck but no permanent sides.

Frame vehicle — A vehicle with skeletal structure fitted with one or more bunk units for transporting logs. A bunk unit consists of a front bunk and a rear bunk that together cradle logs. The bunks are welded, gusseted, or otherwise firmly fastened to the vehicle’s main beams, and are an integral part of the vehicle.

Friction mat — A device placed between the deck of a vehicle and cargo or between articles of cargo, intended to provide greater friction than exists naturally between these surfaces.

g — The acceleration due to gravity, 32.2 ft/sec2 (9.823 m/sec2).

Headboard — A vertical barrier across the front of the deck of a vehicle to prevent forward movement of cargo.

Hook-lift container — A specialized container, primarily used to contain and transport materials in the waste, recycling, construction/demolition, and scrap industries, which are used in conjunction with specialized vehicles, in which the container is loaded and unloaded onto a tilt frame body by an articulating hook-arm.

Indirect tiedown — A tiedown whose tension is intended to increase the pressure of an article or stack of articles on the deck of the vehicle.

Integral locking device — A device that is purposely designed and used to restrain an article of cargo on a vehicle by connecting and locking attachment point(s) on the article to anchor point(s) on the vehicle.

Integral securement system — A feature of roll-on/roll-off containers and hook-lift containers and their related transport vehicles in which compatible front and rear hold-down devices are mated to provide securement of the complete vehicle and its cargo.

Intermodal container — A reusable, transportable enclosure that is specially designed with integral locking devices that secure it to a container chassis trailer to facilitate the efficient and bulk shipping and transfer of goods by, or between various modes of transport, such as highway, rail, sea, and air.

Lateral — Sideways, transverse, crosswise, or across a vehicle.

Lengthwise — Same as “Longitudinal.”

Lift — A tier of dressed timber, steel, or other materials.

Load binder — A binder incorporating an overcenter locking action.

Load capacity — The weight of cargo that a vehicle can carry when loaded to its allowable gross vehicle weight in a particular jurisdiction.

Logs — Include all natural wood that retains the original shape of the bole of the tree, whether raw, partially, or fully processed. Raw logs include all tree species with bark that have been harvested and may have been trimmed or cut to some length. Partially processed logs that have been fully or partially debarked or further reduced in length. Fully processed logs include utility poles, treated poles, and log cabin building components.

Longitudinal — Lengthwise or along the length of a vehicle.

Longwood — All logs, including utility poles, that are not shortwood and are over 16 feet (4.9 m) long. Such logs are usually described as long logs or treelength.

Metal coil — (U.S. only) An article of cargo comprised of elements, mixtures, compounds, or alloys commonly known as metal, metal foil, metal leaf, forged metal, stamped metal, metal wire, metal rod, or metal chain that are packaged as a roll, coil, spool, wind, or wrap, including plastic or rubber coated electrical wire and communications cable.

Pallet — A platform or tray on which cargo is placed so that it can be handled as an article (same as “Skid”).

Pole Trailer — A trailer whose body consists simply of a drawbar by which the trailer is drawn.

Rail vehicle — A vehicle whose skeletal structure is fitted with stakes at the front and rear to contain logs loaded crosswise.

Restrained — An article that is not contained, but is prevented from tipping or shifting.

Rub rail — A rail along the side of a vehicle that protects the side of the vehicle from impacts. Secured — Contained or restrained.

Securing device — Any device specifically manufactured as a means to attach or secure cargo to a vehicle or trailer.

Shackle — A U-shaped metal coupling link closed by a bolt.

Shift — A change in the longitudinal or lateral position or orientation of an article.

Shoring bar — A structural section placed transversely between the walls of a vehicle to prevent cargo from tipping or shifting.

Shortwood — All logs typically up to 16 feet (4.9 m) long. Such logs are often described as cut-up logs, cut-to-length logs, bolts, or pulpwood. Shortwood may be loaded lengthwise or crosswise, though that loaded crosswise is usually no more than 102 inches (2.6 m) long.

Sided vehicle — A vehicle whose cargo compartment is enclosed on all four sides by walls of sufficient strength to contain cargo, where the walls may include latched openings for loading and unloading, and includes vans and dump bodies, and includes a sided intermodal container carried by a vehicle.

Skid — A platform or tray on which cargo is placed so that it can be handled as an article (same as “Pallet”).

Spacer — Material placed beneath an article or between tiers of articles.

Stack — A single column of articles placed one above another.

Stack of logs — Logs aligned parallel and heaped one upon others.

Stake — A member mounted close to vertical on a vehicle frame or as part of a bunk that serves to immobilize cargo placed against it (same as “Standard”).

Stake pocket — A female housing fixed to the side or ends of a vehicle to receive a stake or peg, and may also be used as an anchor point.

Standard — A member mounted close to vertical on a vehicle frame or as part of a bunk that serves to immobilize cargo placed against it (same as “Stake”).

Strapping — A strip of material that may be used to unitize articles and is tensioned and clamped or crimped back upon itself (same as “Banding”).

Tarpaulin (tarp) — A waterproof sheet used to cover cargo.

Tension device — A device used to produce tension in a tiedown.

Tiedown — A combination of securing devices which form an assembly that attaches cargo to, or restrains cargo on, a vehicle or trailer, and is attached to anchor point(s).

Tiedown assembly — A combination of a tiedown with one or more tension devices that secures cargo to the vehicle on which it is being carried.

Tier — Layer of articles that are stacked one upon another.

Tip — An article falls over.

Track — A set of plates on a tractor wheel that provide mobility for a tracked vehicle.

Tractor-pole trailer — A vehicle that carries logs lengthwise so that they form the body of the vehicle. The logs are supported by a bunk located on the rear of the tractor and another bunk on the skeletal trailer. The bunks may rotate about a vertical axis, and the trailer may have a fixed, scoping, or cabled reach, or other mechanical freedom, to allow it to turn.

Transverse — Same as “Lateral.”

Twist lock — A device designed to support and fasten one corner of an intermodal container to a container chassis vehicle.

Unitized load — A number of articles grouped together with sufficient structural integrity that they can be handled, transported, and secured as a single article.

Vehicle — A truck, truck tractor, trailer, or semitrailer individually or in combination.

Void filler — Material used to fill a void between articles of cargo and the structure of the vehicle that has sufficient strength to prevent movement of the articles of cargo.

Wedge — Tapered piece of material, thick at one end and thin at the other.

Well — The depression formed between two cylindrical articles when they are laid with their eyes horizontal and parallel against each other.

Winch — A device for tensioning a webbing or wire rope tiedown that is fitted with means to lock the initial tension.

Working load limit (WLL) — The maximum load that may be applied to a component of a cargo securement system during normal service, usually assigned by the manufacturer of the component.