Pallet glossary
Pallet vocabulary, from deckboard to wane, with the typical dimensions and the standard that defines each term. 92 pages.
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- Bill of materialsA pallet bill of materials (BOM) is the list of every component in one pallet, with its size, material and quantity: deckboards, stringers or blocks, stringerboards and fasteners. A…
- BlockA block is a rectangular, square or cylindrical spacer between the top and bottom decks of a block pallet, specified as width x height x length. Most block pallets use 9 blocks in a 3 x 3…
- Block classBlock class is one of the two pallet classes in the Uniform Standard and PDS: pallets whose top deck is carried on blocks, usually nine in a 3 x 3 grid, tied together by stringerboards.…
- Block stackingBlock stacking is a warehouse storage method in which unit loads are stacked directly on top of one another on the floor, arranged in rows or blocks without racking. The pallets low in…
- Board footA board foot is a volume of wood equal to 144 cubic inches (1 in x 12 in x 12 in). Pallet board feet are calculated as thickness x width x length in inches divided by 144, using actual…
- Bottom deckThe bottom deck is the set of deckboards (or a panel or perimeter frame) on the underside of a pallet, which bears on the floor, conveyor or the unit load below. A GMA-style 48x40 has 5…
- Butted boardsButted boards are deckboards placed tight against a lead board with no gap between them. The Uniform Standard treats two butted 4 in boards as equivalent to one 6 in board, so butting is a…
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- CantA cant is a log that has been squared on two or more sides at the sawmill. In the hardwood industry the cant is often the lower-grade center of the log left after the higher-grade boards…
- ChamferA chamfer is a bevel cut along the edge of a bottom deckboard so pallet-jack wheels can roll up and over the board instead of striking it. The Uniform Standard calls for a 35 to 45 degree…
- Clinched nailA clinched nail is driven completely through the pieces being joined and bent over on the far side, so it holds by the bend rather than by friction. The Uniform Standard requires clinched…
- Combo palletA combo pallet is built from a mix of new and recycled components, for example new stringers with recycled deckboards. In the pallet classification it is Remanufactured/Combo, and like…
- Companion stringerA companion stringer is a repair component fastened alongside a damaged stringer to restore its strength, instead of replacing the stringer outright. The Uniform Standard lists companion…
- CP palletCP pallets are nine standard block pallet designs, CP1 to CP9, used by the chemical and plastics industry in Europe. Each type has a fixed size and construction: CP1 to CP5 are runner…
- CreepCreep is the gradual increase in deflection of a pallet that carries a load over time, even though the load does not change. Wood and especially plastic pallets creep, which is why PDS…
- Cruciform baseA cruciform base is a block-pallet bottom deck made of a perimeter frame plus center connector boards that cross in the middle, forming a cross (cruciform) pattern. It supports the center…
- Cut listA cut list is the production list of how many pieces of each size must be cut for an order: parts per pallet multiplied by the number of pallets. For 1,000 GMA-style 48x40 pallets it reads…
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- Deck coverageDeck coverage is the share of a pallet deck's area that is covered by boards, the rest being gaps. It equals total board width divided by deck length: a GMA-style 48x40 top deck (two 5-1/2…
- Deck gapA deck gap is the open space between two neighboring deckboards. With the end boards flush and interior boards equally spaced, the gap is (deck length minus total board width) divided by…
- Deck matA deck mat is a pre-assembled unit of deckboards and stringerboards on a block pallet, usually fastened with clinched mat nails, which is then nailed down onto the blocks. Typical mat…
- DeckboardA deckboard is a top or bottom deck element laid perpendicular to the stringers or stringerboards, specified as thickness x width x length. On a GMA-style 48x40 stringer pallet the…
- DeflectionDeflection is how far a pallet bends or sags under load, measured at the point of greatest movement. Common limits are about 1.9 to 2% of the span in rack storage (roughly 0.75 in on a 44…
- Dielectric heatingDielectric heating (DH) is an ISPM 15 treatment that uses microwave or radio-frequency energy to heat wood packaging to at least 60 °C for one continuous minute throughout the wood…
- Double-faceA double-face pallet has both a top deck and a bottom deck. It is either non-reversible, with a lighter bottom deck (a GMA-style 48x40 has 7 top and 5 bottom boards), or reversible, with…
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- Fastener withdrawal characteristicThe fastener withdrawal characteristic (FWC, written Cw in the Uniform Standard) is a multiplier that rates how much a nail's threads improve its resistance to pulling out. A plain-shank…
- Floor stackingFloor stacking is the support condition in which a pallet rests on a flat floor, often with other unit loads stacked on top of it. It gives the highest pallet ratings because the floor…
- FlushA flush pallet is one whose deckboard ends line up with the outside faces of the outer stringers or blocks, so nothing overhangs. It is the default construction for GMA-style 48x40…
- Fork tineA fork tine is one of the steel arms on a forklift that slide into a pallet's fork openings to lift it. Tine width, spacing and length decide which openings a pallet needs; a common…
- Free spanFree span is the unsupported distance a pallet must bridge between its supports, such as the clear gap between two rack beams. A 48 in long pallet racked across its length typically has…
- Full four-way entryFull four-way entry means both forklifts and pallet jacks can enter a pallet from all four sides. It comes from block construction: block pallets with a perimeter base, a unidirectional…
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- GMA palletA GMA pallet is the 48 x 40 in (1219 x 1016 mm) wood stringer pallet based on the 1992 Grocery Manufacturers Association specification. It has three notched stringers (partial four-way…
- Green lumberGreen lumber is freshly sawn wood that has not been dried, with moisture content above the fiber saturation point of about 28%. Many hardwood pallets are built green: a GMA-style 48x40 in…
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- Heat treatmentHeat treatment (HT) is the ISPM 15 phytosanitary treatment in which wood packaging is heated until its core reaches at least 56 °C (133 °F) for 30 continuous minutes. Treated pallets carry…
- Helical nailA helical nail (helically threaded or screw-shank nail) has spiral threads along its shank that make it rotate as it is driven, giving much higher withdrawal resistance than a smooth nail.…
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- IPPCThe IPPC (International Plant Protection Convention) is the international plant-health treaty whose standards include ISPM 15, the rule for treating and marking wood packaging such as…
- ISPM 15 markThe ISPM 15 mark is the stamp that shows wood packaging has been treated to the international phytosanitary standard. It contains the IPPC wheat symbol, a two-letter country code, the…
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- Kiln-dried lumberKiln-dried (KD) lumber is wood dried in a heated kiln to a target moisture content, commonly 19% (KD19), 15% or 12%. Kiln drying reduces weight, shrinkage and mold risk, but a KD stamp…
- KnotA knot is the remains of a branch embedded in a board, visible as a round or oval area of cross grain. The Uniform Standard limits sound knots to one half of the cross-section on reusable…
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- Lead boardA lead board (also called an end board) is the outermost deckboard at each end of a pallet's top or bottom deck. Because fork tines and handling impacts hit the pallet ends first, lead…
- Load overhangLoad overhang is when the product or cartons on a pallet extend beyond the pallet's edges. It leaves the overhanging carton walls without support, which reduces their stacking strength and…
- LoadSyncLoadSync is a free desktop tool released by the NWPCA (now Woodpack Global) in 2013 that let pallet users record their requirements (load, storage, stacking and handling) rather than a…
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- Maximum working loadMaximum working load is the largest payload a pallet is allowed to carry in a specific load and support configuration, as defined in ISO 8611-3. Unlike the nominal load, it reflects how…
- Methyl bromideMethyl bromide (MB) is a fumigant gas approved under ISPM 15 for treating wood packaging, shown by the code MB on the mark. It is being phased out and some countries no longer accept it,…
- MIBANTMIBANT stands for Morgan Impact Bend Angle Nail Tester, the impact-bend test for pallet nails defined in ASTM F680. It reports a bend angle in degrees: the lower the angle, the stiffer the…
- Moisture contentMoisture content (MC) is the weight of water in wood expressed as a percentage of the wood's oven-dry weight. Pallet specs treat 19% or less as dry; freshly sawn green wood is above the…
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- Nominal loadNominal load is the load rating produced by the standard ISO 8611 test with rigid beams and applicators. It lets pallets be compared on equal terms, but it is not the payload the pallet…
- NotchA notch is a cutout in the lower edge of a stringer that lets fork tines enter a stringer pallet from the side, making it partial four-way. The Uniform Standard recommends an opening about…
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- Overall heightOverall height is the total height of a pallet from the bottom of its lowest part to the top of its top deck. For a stringer pallet it is top deck + stringer height + bottom deck: a…
- OverhangIn pallet construction, overhang is the distance a deck extends beyond the outer stringers or stringerboards, forming a wing. It is recorded as a single dimension, with zero meaning a…
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- Pallet Design System (PDS)The Pallet Design System (PDS) is the wood pallet design and analysis software from Woodpack Global (formerly NWPCA). First released in 1984 and now at version 6.12, it produces spec…
- Pallet footprintA pallet footprint is its length x width in plan view, with the length (the direction of the stringers or stringerboards) stated first. The 48x40 in (1219 x 1016 mm) footprint is the most…
- Pallet jackA pallet jack (pallet truck) is a hand or powered truck whose forks slide under a pallet and lift it slightly using wheels in the fork tips. Because the wheels must drop to the floor…
- Panel deckA panel deck is a pallet deck made from a sheet of plywood or OSB instead of individual deckboards, giving a smooth, solid surface. The Uniform Standard requires the panel's face grain to…
- Partial four-way entryPartial four-way entry means forklift tines can enter a pallet from all four sides, but pallet jacks only from two opposite ends. Notched stringer pallets such as the GMA-style 48x40 are…
- Perimeter baseA perimeter base is a block-pallet bottom deck made of boards running around all four edges, like a picture frame, leaving the middle of each bay open. It supports the pallet evenly in…
- Plain-shank nailA plain-shank nail is a smooth nail with no threads or rings. Its fastener withdrawal characteristic is 1.0, below the Uniform Standard minimums of 1.5 (single-use) and 1.9 (reusable), so…
- Pooled palletA pooled pallet is owned by a pooling company (such as CHEP, PECO or iGPS) and rented to shippers, who pay per use or trip instead of buying pallets. North American pooled pallets are…
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- Rack storageRack storage is the support condition where a pallet sits on two (or three) rack beams with nothing underneath, so the pallet itself must span the gap. It usually gives a pallet's lowest…
- Remanufactured palletA remanufactured pallet is built from recovered (recycled) pallet components, often disassembled and rebuilt to a new size or design. It is one of the manufacture classes in the pallet…
- Reusable palletA reusable pallet (multiple-use or multi-trip) is designed to make many trips and be repaired along the way. The Uniform Standard sets higher lumber quality and fastener minimums for…
- ReversibleA reversible pallet is a double-face pallet whose top and bottom decks are identical, so either face can carry the load. It appears in the classification string as Double-Face Reversible…
- RFQAn RFQ (request for quote) is the document a buyer sends to pallet suppliers asking them to price a pallet. A good pallet RFQ states the size, the load and how it is supported and handled,…
- RunnerA runner is the long base member of a skid or single-face pallet, effectively a stringer that rests directly on the floor. On plastic pallets, runners are the continuous rails under the…
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- Safe working loadSafe working load (SWL) is the maximum load a pallet is rated to carry in a specific support condition, such as racked, on a forklift or floor-stacked, with a safety margin built in. It is…
- ShinerA shiner is a nail that misses the stringer or block it was meant to enter, so its shank or point shows on the side of the member or sticks out of the pallet. The Uniform Standard allows…
- ShookShook is lumber that has been cut to the finished sizes of pallet or box parts, such as deckboards, stringers and blocks, ready for assembly. Pallet mills cut shook from cants or rough…
- Single-faceA single-face pallet has only a top deck: its stringers, runners or blocks rest directly on the floor with no bottom deck. A skid is the most common example. It uses less wood than a…
- Single-use palletA single-use pallet (also called expendable, one-way or limited-use) is designed to make one trip before being discarded or recycled. The Uniform Standard allows lower lumber quality and…
- SkidA skid is a pallet with no bottom deck: a top deck fastened across two or more runners (stringers) that sit directly on the floor. Skids are used for machinery, crate bases and loads that…
- Slip sheetA slip sheet is a thin sheet of corrugated, solid fiberboard or plastic placed under a unit load in place of a pallet, with one or more tabs that a push-pull forklift attachment grips.…
- Slope of grainSlope of grain is the angle between the wood fibers and the long axis of a board, stated as a ratio such as 1 in 4 (the grain drifts 1 in across for every 4 in along). The Uniform Standard…
- Solid deckA solid deck is a pallet deck with no gaps between the deckboards, made either from boards butted edge to edge or from a single plywood or OSB panel. It is used for small cartons, bags,…
- Specific gravitySpecific gravity (G) is the density of wood relative to the density of water, a dimensionless number. It is the main wood property in pallet connection design: in the Uniform Standard's…
- SplitA split is a lengthwise separation of the wood fibers that runs through the piece. The Uniform Standard limits splits in deckboards to one third of the board length on reusable pallets…
- StapleA staple is a two-legged wire fastener driven with a pneumatic tool, used on some pallets instead of nails. Pallet staples come in round or rectangular wire (commonly 14 to 16 gauge), are…
- Strap slotA strap slot (banding notch) is a recess cut in the top of a stringer or under the top deck so that strapping or banding can pass beneath the deckboards and hold the load to the pallet.…
- Stretch wrapStretch wrap (stretch film) is a plastic film stretched around a loaded pallet so that its tension holds the cartons together and ties the load to the pallet. Pallet design tools such as…
- StringerA stringer is a continuous beam that runs the full length of a stringer pallet between the top and bottom decks, specified as width x height x length. A GMA-style 48x40 uses three 1-3/8 x…
- Stringer classStringer class is one of the two pallet classes in the Uniform Standard and PDS: pallets whose decks are supported by continuous stringers running the full length. The GMA-style 48x40 is…
- StringerboardA stringerboard is a full-length board on a block pallet that sits between the deckboards and the blocks and ties the blocks together, specified as thickness x width x length. The EPAL 1…
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- Third-angle projectionThird-angle projection is the orthographic drawing convention used in the United States, in which each view is placed on the side of the object it shows: the top view above the front view…
- Tier sheetA tier sheet, also called a layer pad or tier pad, is a flat sheet of corrugated board or plastic placed between layers of product on a pallet. It spreads load across the layer below,…
- Title blockA title block is the boxed area, usually in the lower-right corner of a technical drawing, that identifies the drawing: title, drawing number, revision, date, scale, units, projection and…
- Top deckThe top deck is the load-carrying surface of a pallet: the top deckboards (or a plywood or OSB panel) fastened across the stringers or stringerboards. A GMA-style 48x40 top deck has 7…
- Two-way entryA two-way entry pallet accepts fork tines from two opposite ends only. An unnotched stringer pallet is the classic example: forks slide in between the stringers from either end, and the…
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- Unidirectional baseA unidirectional base is a block-pallet bottom deck whose boards all run parallel in one direction, with no crosswise bottom boards. It is a full four-way design: forklifts and pallet…
- Unit loadA unit load is a pallet together with the product, packaging and stabilizers (such as stretch wrap or straps) that are secured to it so they can be handled as a single item. Designing the…
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- WaneWane is bark, or a lack of wood, along the edge or corner of a board where the log's rounded outer surface ran through the piece. The Uniform Standard limits wane separately for exposed…
- Wheel openingA wheel opening (hand-jack opening) is a space in a pallet's bottom deck where the load wheels of a pallet jack can drop through to the floor. On a GMA-style 48x40 stringer pallet the…
- WingA wing is the part of a pallet deck that overhangs beyond the outer stringers or stringerboards. On a single-wing pallet only the top deck overhangs; on a double-wing pallet both decks do.…
- Woodpack GlobalWoodpack Global is the new name of the National Wooden Pallet & Container Association (NWPCA), the US trade association for the wood pallet and container industry. It publishes the Uniform…