Loading dock

A loading dock or loading bay is an area of a building where goods vehicles (usually road or rail) are loaded and unloaded. They are commonly found on commercial and industrial buildings, and warehouses in particular.

Loading docks may be exterior, flush with the building envelope, or fully enclosed. They are part of a facility's service or utility infrastructure, typically providing direct access to staging areas, storage rooms, and freight elevators.

In order to facilitate material handling, loading docks may be equipped with the following:

Warehouses that handle palletized freight use a dock leveler, so items can be easily loaded and unloaded using power moving equipment (e.g. a forklift). When a truck backs into such a loading dock, the bumpers on the loading dock and the bumpers on the trailer come into contact but may leave a gap; also, the warehouse floor and the trailer deck may not be horizontally aligned. In North America, the most common dock height is 48–52 inches (120–130 cm), though heights of up to 55 inches (140 cm) occur as well. A dock leveler bridges the gap between a truck and a warehouse to safely accommodate a forklift.

Where it is not practical to install permanent concrete loading docks, or for temporary situations, then it is common to use a mobile version of the loading dock, often called a yard ramp.

There can be very serious accidents on loading bays. One example is trailer creep (also known as trailer walk, or dock walk), which occurs when the lateral and vertical forces exerted each time a forklift truck enters and exits the trailer cause the trailer to slowly move away from the dock, resulting in separation from the dock leveler. Factors that affect trailer creep are the weight and speed of the lift truck and load, the gradient of the ground the trailer is parked on, the condition of the suspension, tire air pressures, the type of transition being used (dock levelers, dock boards), and whether the trailer has been disconnected or if it is still connected to the tractor.

Separation of a vehicle from the loading dock also occurs when a driver prematurely pulls away while the truck is still being loaded/unloaded. This issue is usually caused through a driver not correctly observing traffic lighting signals on a loading bay which prohibit the movement of the trailer. It is also important to ensure that drivers are adequately trained on the safe system of work they are expected to follow.

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