Anchor bolts

Used to secure a racking system to the floor, so it maintains its position.

Base plate or footplate

A plate welded to the foot of a rack upright or repair unit to distribute the weight of the rack to the floor and allow it to be anchored.


A horizontal structural component of the rack system that bears the weight of the stored loads and transfers it to the uprights it is connected to.

Beam connector

The rack component that secures the beam to the upright.


Diagonal and horizontal rack components configured in such a way that they follow a pattern and improves the stability of the racking system.

Column guard

A protection place on or in front of a rack to prevent damage.

Double column

A racking layout with back to back rows of 2 deep selective rack.

Pallet support bars

A component placed perpendicular to a beam to allow for a pallet load to be placed on it when it cannot be placed on the support beam.

Row spacer

Used for the spacing of back to back pallet rack bays, providing stability in the rack system.

Safety bar

Recommended but not mandatory, they prevent a pallet from falling through the rack.

Safety pin

A small device installed on a beam connector to prevent a dislodgement from the upright frame.


Inserted between the concrete floor and the foot plate, they must always match the size of the base plate.

Upright frame

Refers to 2 uprights columns (front and rear) and the bracing members between them. Their depth can vary.

Uprights column

Vertical parts of a racking system, on which horizontal and diagonal braces are welded and beams are attached to.

Wire mesh decking

Accessory installed on a rack to prevent stored merchandise from falling through the rack


Back to back

A common rack configuration, this type of pallet racking is composed of two consecutive back-facing rows.

Cantilevered rack

Not intended for storing palletized loads, they are great for storing long or cumbersome objects. They provide useful but low-density storage.

Double deep

This type of rack configurations allows for the storage of goods, two rows deep. Storage density is increased.


A forklift can travel deep within the rack for placement and retrieval of loads. Beams run the depth of the rack's structure.


A drive-thru rack allows forklifts to go through the entire length of the rack, it is accessible from both ends.

Dynamic rack

Refers to 2 types of rack systems: mobile racks and gravity pallet racks.

Fixed rack

A static racking system that stores palletized goods

Gravity flow

The pallets stored in this system are placed on sliding rails, and one side of the rack is slightly lower than the other. Gravity is used to move items.

Mobile rack

Compact, space saving, and often motorized, these racks are set-up on a rail system that allows the displacement of entire rows at a time.

Pallet flow rack

A system that incorporates sections of a conveyor so that cartons or pallets can flow to the front

Single deep

This type of rack configuration allows easy access to stored pallets, 1 pallet row deep. It requires several aisles, thus increase material handling operations.

Static rack

Refers to 2 types of rack systems: fixed storage racks and drive-in/drive-thru pallet racks.



The space between racking systems that allows forklift and personnel to maneuver in and around the racking systems. A standard aisle width is 12'.


A bay refers to the space between two upright columns, in a racking system.

Beam deflection

Beams are generally designed to accommodate vertical deflections that do not exceed 1/180 when loaded.

Building column

A structural column that holds the building or warehouse's roof or ceiling.


Is the compartment or space between two uprights, on one beam level, which generally accommodates 2 pallet positions.


The necessary space between the racking system and the walls or the pallets.

Counterbalanced lift truck

This is a lifting device that can lift and move a load without the use of outriggers to stabilize the unit. It has a weight at the back to counterbalance the load.

Flue space

The clearing space within a racking system that allows heat from a fire to vent vertically and allows sprinklers to operate as quickly as possible in case of fire.


A vehicle with a pronged device in front for lifting and carrying heavy palettized loads.

Load capacity

It's the max weight permitted to be placed on the rack. Several elements. The rack height, type, and beams all determine the rack's capacity to bear a load.

Load plaque

Warehouse operators should display a plaque, a type of signage, communicating the rated load capacity of the pallet rack and the maximum weight it can hold.

Order picking truck

This is an electric lift truck designed for filling individual customer orders that require piece-part or case picking.


The parts of a forklift that project forward and are used to stabilize it. They are often responsible for the damages found at the base of the racks.


A flat structure used as a base for the storage and unitization of goods in the supply chain.

Pallet jack

A tool for lifting and moving pallets, steered by a 'tiller' like lever that also acts as the pump handle for raising the jack.

Pallet stopper

A rack accessory used to stop a pallet from going too far into the rack and damaging it.

Reach fork truck

Forklifts with mechanisms that allow trucks to extend out further, for tight areas where a normal lift truck would have limited space to maneuver.

Roll formed rack

This type of rack is cold roll-formed steel. They are made of thinner gauge steel but derive their strength from their shape.


A series of rack bays arranged together to form a section of a racking system.

Row spacer

Used if uprights are arranged in back-to-back rows; the spacers are mounted between columns to ensure that the rows are kept straight and to give the pallet racks even more strength and steadiness.

Seismic zone

An area prone to earthquakes, requiring that racks and buildings meet rigorous standards.


To fill the space between upright footplates and the floor, when the floor is uneven or not level.

Structural rack

This type of rack is hot-rolled structural steel that has a greater weight-bearing capacity with the beams bolted on to the upright frames.

Tunnel bay

A cross-aisle that goes right through the warehouse rack system, allowing forklift traffic to safely pass through.


An aisle or space reserved for pedestrian traffic

Wall spacer

Ensures a consistent space and clearance between the racking system and the wall of the building.



American National Standards Institute.


Canadian Standards Association (CSA) has issued guidelines on industrial steel storage racks


Load Application and Rack Configuration drawings are provided when a racking system is purchased from the manufacturer. They contain the configuration of the installed rack as well as the load capacity of the system.


The Original Equipment Manufacturer (i.e. the pallet rack manufacturer that initially produced the rack)


Occupational Health and Safety Act.


The Protective Guarding Manufacturers Association, of which Damotech is a member. They are the industry's leading suppliers of fixed protective guarding products.


Pre-start Safety Review (required for any modifications to the rack in the province of Ontario, Canada)


It's a voluntary program for manufacturers of industrial steel storage racks. This certification assures accordance with RMI’s ANSI MH16.1-2012 Guidelines


The Rack Manufacturers Institute. Members are suppliers of industrial steel storage racking Systems.


Refers to a Very Narrow Aisle


Column buckling

Buckling is characterized by a sudden sideways deflection of a structural member.

Nominal strength

The actual strength of a material or a structural member. It’s the capacity of a structure to take the load.

Out of plumb

This occurs when the rack is not vertical and is leaning. It will reduce the capacity of a rack column.

Out of straight

This occurs when the rack is bowed, generally in the middle.  it too can reduce the capacity of a rack column.

Torsional buckling

When an applied load causes both lateral displacement and twisting of a member lateral torsional buckling has occurred.

Unit load

A number of items can be stored on a pallet, whose load counts as one unit.