The Pallet Design System (PDS) is the NWPCA-developed software for engineering pallet specifications.
Detailed Definition
The Pallet Design System, known as PDS, is engineering software from the NWPCA that estimates how a wood pallet design will perform before it is built. The user enters the pallet's dimensions, component sizes, lumber species and grade, fasteners, load type and support conditions, and the program estimates load capacity and deflection for situations such as floor stacking, fork handling and rack spans. Manufacturers use it to size components for a target load and compare design options. Physical test methods such as ASTM D1185 remain the way to verify performance.
Inputs that drive a PDS result
The program can only be as good as the description it is given. The most important inputs are:
- Overall size and deck board count, widths and thicknesses.
- Stringer or block sizes and any notches.
- Species group, lumber grade and moisture condition.
- Fastener type, size and count per joint.
- Load type, such as uniform or concentrated, and support condition, such as racked across the length or width, on forks, or on the floor.
If any input is guessed rather than measured, the capacity estimate carries that uncertainty with it.
Reading the output
PDS reports capacity for specific support conditions, so a single capacity figure on a quote is incomplete unless it says which condition it describes. A pallet rated for a heavy floor stack may carry far less when racked across an open span. Ask for the racked capacity in the direction your rack actually supports the pallet, along with the deflection limit used. If the load is unusual, such as a point load or a bag that drapes between boards, a physical test under ASTM D1185 or ISO 8611 may be worth the cost.
Authoritative Sources
- National Wooden Pallet & Container Association (NWPCA): the US trade association representing wood pallet manufacturers, recyclers, and component producers, founded in 1947.
- ASTM International (ASTM): the global standards body that publishes ASTM D1185 (Standard Test Methods for Pallets and Related Structures Employed in Materials Handling and Shipping).
Related Glossary Terms
Frequently Asked Questions
Does a PDS report replace pallet testing?
Not always. Design software is a fast way to compare options and size components, and for routine designs and loads many buyers accept its estimates. Physical testing is still useful for new or critical designs, unusual loads, or when the cost of a failure is high. Testing to ASTM D1185 or ISO 8611 shows how samples of the actual pallets behave, including the effects of real lumber quality and fastening.
Do pallet buyers need to run PDS themselves?
Usually not. PDS is distributed through NWPCA and is mainly used by pallet manufacturers, designers and packaging engineers. A buyer can instead ask the supplier for the design report showing the inputs and the rated capacities for each support condition that matters. Keep that report with your pallet specification so later orders can be checked against the same design.