User:Mgkay/Pallet racking Load containment systems

Note: recommend that this be a top-level section of Pallet racking  instead of subsection under Safety considerations because current Safety section needs to be re-written and expanded

Load containment systems for pallet racks
Pallet racks are used throughout industry and distribution facilities for bulk storage of items. Generally, the items stored are boxed goods stacked on pallets which are placed on the rack. The pallets are accessed by some type of mechanized lifting and retrieval device. Sides of a pallet rack must be accessible by the mechanized device for storage and retrieval of goods. Thus these "access sides” must be open; entry to them cannot be permanently blocked/guarded.

However, there are instances where an aisle way is designated along a row of pallet rack for pedestrian or other traffic and not for operational access by the lifting or retrieval device. When a pedestrian or other traffic aisle way is designated along a run of pallet racking it is good practice to guard the aisle way from a potential hazard created by objects that may fall from the pallet rack. In these situations, load containment systems are added to the designated aisle way side of the pallet rack to prevent or control any item from falling off of the back of the rack system or potentially falling on and injuring a person in the aisle way. Containment systems may also be placed between back to back installations to prevent items on one side of rack potentially pushing items off the adjacent rack.

There are two types of load containment systems for pallet racking, steel mesh containment panels and netting containment systems.

Netting containment systems
Load containment safety netting was originally adapted from cargo-based maritime netting used throughout the centuries for nautical trade and exploration. Safety netting has found widespread industrial use in load containment, driven in part by the post-war expansion of warehouse distribution systems. Netting types of varying break-strength and deflection allowances can be used within a load containment netting system. Widely accepted as an alternative to metal or other solid barrier systems, load containment safety netting provides a light weight, high-strength, easily customizable means to protect goods and personnel while allowing airflow, humidity control and clear visibility within sectioned containment areas.

Netting containment systems are used on rack bays or gravity-flow rack channels to contain loose or falling objects. Palletized parts or boxes can become dislodged during bay loading. Rack netting containment systems can be placed vertically at the front, or pick face, and/or at the rear sides of racking systems prevent dislodged objects or full pallets from falling. Netting containment systems can be applied across multiple bays or as single bay units and secured by varying fasteners determined by frequency of access, load requirements and net or load sizes. Actuating systems can also be found in current netting containment systems to allow remotely operated rack bay access by use of pull cords or other means. In addition to vertical placement, horizontal netting can also be utilized in rack systems to protect against objects falling from one level to another or into tunnel areas, and to provide barriers between storage between and rack supports.

Steel mesh containment panels
As the distribution industry grew, alternative methods were sought for containing items dislodged from palletized storage while stored on pallet rack systems. Distributors found steel wire mesh panels were a viable alternative to netting containment systems. The following are the two types of steel mesh containment panels used for pallet racking:
 * Framed steel wire mesh panels are constructed of steel wire mesh welded or woven into a square, diamond, or rectangular pattern. welded or otherwise fixed into a shaped steel frame. The panels are mechanically attached to the existing Pallet Rack uprights with brackets. The panels may be mounted flush with the rack uprights, or more commonly, offset by several inches to allow for load overhang.
 * Unframed steel wire mesh panels are constructed of welded wire mesh with a bond shear edge (no tails on the edge) mechanically attached to the existing upright posts by the way of stand-off brackets, or sleeves of various lengths.