Pallet performance is often discussed in terms of materials, dimensions and load capacity, but much of what determines whether a pallet works successfully happens after it enters the warehouse or distribution system. It must be picked up by a forklift or pallet jack, positioned under a load, stacked or stored, moved through doorways and trailers, and increasingly travel across conveyors or interact with automated equipment.
Those everyday handling conditions help explain why seemingly minor pallet characteristics can matter. Fork-entry clearance affects how easily equipment engages the pallet. Bottom deck configuration can determine how well it travels on conveyors. Damage or excessive deflection that causes little difficulty in conventional forklift handling may be enough to stop an automated system.
This page focuses on the physical handling and movement of pallets and palletized loads. Pallet ownership, retrieval and pooling systems are covered separately in Pallet Rental, Pooling & Management.
Jump to: Forklift & Pallet Jack Handling | Empty Pallet Handling | Palletized Load Stacking | Trailer Loading | Storage & Racking | Conveyors & Automation | Palletizing & Depalletizing | Retail & Public Safety | Damaged Pallets
1. Forklift and Pallet Jack Handling
The modern pallet developed alongside mechanized materials handling, and its basic purpose remains closely tied to the equipment used to move it. Forklifts, pallet jacks, walkie stackers and other lift trucks engage the openings beneath the pallet so that an entire unit load can be moved at once.
Not all pallet entry is the same. A two-way stringer pallet normally provides unrestricted fork entry from only two directions. Notched stringers can provide four-way forklift access, although pallet jack entry from the sides may still be limited. Block pallets generally provide full four-way entry and can offer greater flexibility where loads must be approached from different directions.
Those distinctions can have practical consequences in trailers and confined warehouse locations. A pallet that can be picked up from any side gives an operator more loading options and may make better use of available floor space. Equipment compatibility should therefore be considered when specifying the pallet rather than discovered after pallets arrive on the dock.
Operators should also avoid treating the pallet as an indestructible part of the load. Fork tips can break deckboards, damage blocks or stringers, and puncture the product above if forks are positioned incorrectly or enter too far. Repeated impact damage can shorten pallet life and eventually create problems elsewhere in the supply chain.
2. Empty Pallet Handling and Stacking
Empty pallets create a different handling problem from loaded pallets. They may be relatively light compared with the products they carry, but repeated manual lifting, awkward dimensions, protruding nails and damaged boards introduce ergonomic and injury risks.
Where pallets are stacked manually, workers should be trained in appropriate lifting practices and provided with the personal protective equipment required for the workplace. Heavier pallets may require team lifting or mechanical assistance. Broken pallets should be segregated rather than allowed to accumulate beside usable stacks, where they can inadvertently find their way back into service.
Stacks should be built on a level surface, with pallets of similar dimensions aligned squarely. Smaller pallets placed beneath larger ones can reduce stability, while pallets stored vertically or leaned against walls can be knocked over. Stack locations also need to avoid pedestrian routes, emergency exits, electrical panels, fire protection equipment and other areas where pallet storage can create a secondary hazard.
Fire codes and insurer requirements may place additional limits on idle pallet storage, including stack height, pile size and separation distances.
See Pallet Stacking and Unstacking Safety for Material Handlers for a more detailed discussion of manual handling and empty pallet storage.
3. Stacking Palletized Loads
The term pallet stacking can also refer to stacking loaded pallets one on top of another, often called block stacking. The issues are quite different from those involved in stacking empty pallets.
A block-stacked load depends on the pallet, packaging and product beneath it to support the weight above. Loads should be stable, reasonably uniform and positioned so that upper pallets do not impose loads where the packages or pallet below cannot support them.
Pallet condition is particularly important. A missing board, damaged block or weakened stringer can affect the stability of the stack even where the individual pallet could still be moved successfully at floor level. Product overhang, uneven load distribution and poorly contained loads add further risk.
The floor itself also matters. Block stacking requires a level, suitable surface and enough room to place and retrieve loads without creating unstable stacks or obstructing travel routes.
For a closer look at the safety considerations, see Block Stacking and Unstacking Loads: Safety Precautions.
4. Trailer Loading and Transportation
Pallet dimensions, entry configuration and load orientation all influence how efficiently a trailer can be loaded.
With the standard 48 × 40-inch North American pallet, for example, a 53-foot trailer commonly accommodates 26 pallets when they are loaded straight. Depending on the pallet and handling equipment, sideways or pinwheel loading can make more efficient use of the trailer floor. A stringer pallet that can be entered from the side by a forklift may still present problems for a pallet jack, so the theoretical maximum number of pallet positions is not always the practical maximum.
Weight can become the limiting factor before floor space is exhausted, particularly with dense products. Load height, product stability and allowable compression determine whether pallets can be double-stacked.
Overhang is another easily overlooked variable. A nominal 48 × 40-inch pallet load is no longer effectively 48 × 40 if cases extend several inches beyond the pallet edge, which can disrupt otherwise efficient trailer loading patterns while also exposing the product to damage.
See How Many Pallets Fit in a Truck: Capacity by Trailer Size for pallet counts by trailer size and loading orientation.
5. Pallets in Storage and Racking
A pallet resting on the floor is supported very differently from one stored in warehouse racking. In floor storage, much of the pallet base may be supported. In selective rack, support may be concentrated at two rack beams with a substantial unsupported span between them.
That difference affects pallet deflection and the stresses imposed on pallet components. A pallet that performs satisfactorily during floor handling cannot automatically be assumed to have adequate capacity for edge-rack storage.
The load itself also affects performance. Weight distribution, pallet orientation, component stiffness and the way packages interact with the pallet all influence how the unit load behaves in storage.
Facilities should therefore specify the actual support conditions a pallet will encounter. Descriptions such as “rackable pallet” have limited value without knowing the rack span, load weight, orientation and acceptable deflection.
For more on the distinction between dimensions, testing and performance requirements, see Pallet Standards & Specifications.
6. Pallets on Conveyors and Automated Systems
Automation has made pallet consistency increasingly important. A skilled forklift operator can sometimes compensate for a slightly damaged or distorted pallet. A conveyor, sensor or automated storage system generally cannot make the same judgment.
Conveyor compatibility begins with the pallet base. Bottom deckboards or runners must provide appropriate support as the pallet moves across rollers or other conveying surfaces. Large openings, damaged boards, excessive deflection or inappropriate runner orientation can result in poor tracking, vibration or jams.
Automated storage and retrieval systems can impose additional requirements for dimensional accuracy, fork-entry clearance, pallet stiffness and bottom deck geometry. Automated guided vehicles and autonomous mobile robots likewise depend on predictable interfaces when picking up and positioning pallets.
The issue is not simply whether a pallet is strong enough to carry the product. A pallet can have adequate load capacity and still be a poor automation pallet because it is inconsistent, damaged, excessively flexible or incompatible with the equipment interface.
An earlier RPN article explored this issue with Ralph Rupert, formerly of Virginia Tech’s Center for Unit Load Design: Pallet Design for Automated Systems: Forget Pallets at Your Peril.
7. Palletizing and Depalletizing
Palletizing is the process of building a unit load on a pallet, while depalletizing reverses the process at the receiving end. Both can be performed manually or with automated equipment.
Conventional palletizers often form complete layers of product before placing them on the pallet. Robotic systems can provide greater flexibility where plants handle multiple products, package sizes or stacking patterns. Automated depalletizing increasingly uses sensors and machine vision to identify and remove cases, bags or other products from incoming pallet loads.
For the pallet itself, the important questions concern the interface. The pallet must arrive in the correct position, provide a stable base for load building and perform consistently with conveyors, dispensers and other equipment surrounding the palletizer. Empty pallet dispensers, for example, depend on pallets separating reliably from a stack rather than catching on damaged boards, protruding fasteners or one another.
Broader subjects such as robotics, machine vision, warehouse control systems and Industrial IoT extend beyond pallet handling and will be covered separately within the Pallets Hub’s technology and automation resources.
8. Pallet Safety Beyond the Warehouse
Pallet-related safety concerns do not end at the shipping dock. Pallets are routinely encountered in retail stores, garden centers, parking lots and other public locations, where the people around them may have little or no material handling training.
Damaged boards, exposed nails, unstable displays and pallets standing vertically can create risks that would normally be controlled in an industrial workplace. Children can be particularly vulnerable when pallets are accessible in public or residential settings.
RPN has covered this issue in several articles:
- Pallet Safety Study: After Shipping, Pallets Pose Big Risk to Public
- 4 Tips for Pallet Safety on the Retail Floor
- Pallet Safety at Home and on the Retail Floor
9. Handling Damaged and Unwanted Pallets
Pallet damage should be addressed before a pallet fails under load or creates a problem for handling equipment. Facilities benefit from having a defined process for identifying suspect pallets, removing them from the usable supply and determining whether they should be repaired, returned to a pool, recycled or otherwise removed.
Ownership should be established before disposing of pallets. Rental and pooling pallets generally remain the property of the pool operator, while other marked pallets may also be subject to recovery arrangements.
Unwanted whitewood pallets can often be reused or repaired by pallet recyclers where there is sufficient local demand. Pallets that are no longer suitable for reuse may still have value as recovered wood or other recyclable material, depending on their construction and local markets.
See Pallet Removal and Pallet Disposal Solutions for options when unwanted pallets begin accumulating at a facility.
