The efficient operation of warehouses and distribution centers heavily relies on the rational distribution and precise positioning of goods. Even with advanced industrial storage systems, improper placement of goods can hinder workflows and potentially damage both products and workers. Therefore, monitoring unit loads is critical in warehouse safety management.
A unit load refers to a group of products arranged systematically on a support platform to form an integrated logistics unit that facilitates handling and transfer. This unit could be product packaging, containers, or most commonly - pallets, which serve as primary support structures in pallet racking systems.
A pallet is a flat transport structure that provides a stable base for stacking goods. Consisting of a sturdy frame, it allows for even distribution of weight across its surface. Forklifts or pallet jacks can easily move pallets along with their cargo between storage racks or warehouse areas.
Pallets can be categorized by various factors including dimensions and materials. Below we examine the main types and their characteristics.
The standard European pallet measures 1200×800 mm and dominates European logistics, with approximately 500 million units in circulation according to the European Pallet Association (EPAL). As an ISO-certified standard, it's designed to maximize loading space in trucks and containers (typically 2400 mm wide).
Key specifications:
- Construction: 11 wooden boards, 9 blocks, 78 nails
- Weight: ~25 kg
- Dynamic load capacity: 1500 kg
- Static load capacity: 5500 kg (when stacked on solid ground)
EPAL-marked pallets feature identification codes and handling instructions.
Common in U.S. and Japanese logistics, this standard measures 1200×1000 mm.
Key specifications:
- Weight: ~25 kg
- Dynamic load capacity: 1500 kg
- Static load capacity: 6000 kg (on stable surfaces)
Additional standardized dimensions include 1016×1219 mm, 1165×1165 mm, 1067×1067 mm, and 1100×1100 mm, though these see limited use compared to Euro or American standards.
Entry points determine accessibility for forklift operations:
- Four-way entry: Accessible from all sides
- Two-way entry: Only accessible from opposite sides, offering less mobility
Dominating 90-95% of the market, wooden pallets offer:
Advantages:
- Durability and easy repair
- High recyclability
Disadvantages:
- Susceptible to structural damage from impacts
- Difficult to thoroughly clean and sanitize
Note: All wooden pallets must comply with ISPM 15 regulations for international trade, requiring debarked wood with phytosanitary treatment.
A growing alternative with distinct characteristics:
Advantages:
- Easier cleaning and sanitation
- Lighter weight and impact resistance
- Fully recyclable
Disadvantages:
- Prone to deformation under excessive loads
- Higher cost than wood
- Irreparable when damaged
Constructed from steel or aluminum, these represent the most robust option, primarily for heavy industrial use.
Advantages:
- Exceptional strength and impact resistance
- Easy cleaning and sanitation
- High weight capacity
Disadvantages:
- Significant weight increases transport costs
Designed for lightweight applications:
Advantages:
- Disposable and recyclable
- Low cost and easy handling
Disadvantages:
- Single-use only
- Double-faced pallets: Loadable from both top and bottom
- Closed pallets: Single loading surface with enclosed opposite side
- Wing pallets: Feature extended edges for secure fastening
Proper loading techniques ensure product integrity and operational safety:
- Eliminate gaps between stacked pallets to prevent instability
- Alternate pallet orientation in transport vehicles for balanced weight distribution
- Never exceed pallet dimensions - use shrink wrap for overhanging loads
- Calculate height and weight parameters for optimal space utilization
- Position goods to facilitate forklift access and movement