90º stacking

Placement or retrieval of a pallet where the forklift truck makes a 90° turn to face the rack during the placement or retrieval process.

Intrusive stacking

Placement or retrieval of a pallet where the turning radius or length of fixed-fork lift truck is greater than the aisle width and part of the storage location concerned is used by the truck forks and load when turning to place or retrieve a pallet.

Allowable loading

Beam, frame or shelf safe load capacity indicated by the storage equipment supplier to the user on the safe load warning notices based upon the data supplied by the specifier.

Compartment load

Load, which can be loaded into one compartment of a rack or shelving structure from one side.

Frame load

Total allowable weight of all the loads transmitted to the frame by the members attached to the frame.

Bay load

Total allowable weight of all the unit loads in a bay of racking not including any unit loads that can be stored on the floor of the bay.

Total racking or shelving load

Total allowable load supported by all the primary load supporting members.

NOTE: This may be the total load from beams or shelves in a defined area of racking or shelving.


Floor construction on which the equipment is erected and to which it is fixed to provide anchorage and stability.

Truck operator

Person trained and responsible for the safe use of an individual fork lift truck or a range of such equipment.

NOTE: This would normally be rider-controlled equipment but could also include pedestrian-controlled powered equipment together with hand-operated pallet trucks.

LMA (load make up accessory)

Storage unit for the handling of loads by lift trucks.

NOTE: Examples of load make up accessories include pallets, containers, bins, boxes, barrels and stillages.

MHE (mechanical handling equipment)

Equipment used to transport the unit load to be stored.


Detailed description of the user’s requirements including the racking specification and other data such as the ambient storage conditions, the floor construction, local authority requirements, etc. including all details affecting either the design of the installation or its construction.


Person or company that provides the supplier with a specification based on the user’s requirements.

NOTE: The specifier can be a consultant or other specialist, the end user or the equipment supplier acting as the specifier.

Crane racking

Pallet racking arranged as a very narrow aisle system and operated by a stacker crane running on a rail and laterally supported by the racking structure.

Pick up and Deposit stations (P and D stations)

Storage locations at the end of an aisle used as an interface between different types of mechanical handling equipment.

NOTE: The P and D stations can be used as an interface between the unit load and handling equipment that is dedicated to the rack aisle (such as very narrow aisle (VNA) trucks or cranes) and the conveyors or free movement trucks which service the installation. The P and D stations can also be used to accurately fix the location of the unit load relative to the racking. This is often used by trucks or cranes having a fixed length of fork stroke and ensures accuracy in the X and Z directions when placing the unit load onto the racking beams.


Consists of submitting your storage equipment and shelves to periodic reviews (at least once every 12 months) applying the UNE EN 15635 standard and the NTP 852 prevention technical note, and carried out by external, independent and competent personnel. A written record of these inspections must be kept in order to be made available to the competent labor authority, if required. Remember that your shelves are work equipment and are subject to the provisions of Royal Decree RD 1215/1997.

APR (Adjustable Pallet Racking)

Steelwork structure consisting of frames and beams adjustable in height, specifically designed to support load make up accessories and unit loads.


Nominal dimension between items.


Trained and qualified as a competent person who assembles and builds the racking at the site location.

NOTE: The installer should be trained and experienced in the work to be done and should be properly supervised and controlled to ensure that the health and safety of workers and others is safeguarded.


Portable platform, with or without superstructure, for the assembly of a quantity of goods to form a unit load for handling and storage by mechanical appliances.

Competent person

Person who by means of a combination of training, experience and education has the knowledge to carry out the task and safety requirements effectively.

PRSES (Person Responsible for Storage equipment safety)

Person appointed by the warehouse management with responsibility for maintaining the safe operation of the warehouse storage system.


Company that supplies the storage equipment.

NOTE: The company can be the original manufacturer or an intermediate company acting as a distributor.

Pallet safety back stop (Type A)

Safety device, which protects against unintentional load movement within the racking and prevents loads from protruding or from falling into an aisle or into an area accessible to people.

Pallet safety back stop (Type B)

Backstop to prevent accidental damage, usually placed at the back of a storage compartment, to prevent the accidental collision of a pallet or its load with other equipment, such as sprinklers, when a load is placed in the storage compartment.

Pallet safety back stop

Safety back stop to prevent accidental collision of a pallet or its load with other unit loads or equipment, when that load is placed in the storage compartment.

Pallet buffer back stop

Buffering back stop which is specified as an aid for use by forklift truck drivers to deposit a unit load in the correct position in the racking.

Specified allowable load

Unit load allowed in the storage equipment.

Unit load

Weight of an individual stored item that can be placed or retrieved in one operation.


Company or person who manages and operates the installation on a daily basis and is responsible for the continuing safety of the installation.