Guide: FM 4996 and UL 2335
FM 4996 and UL 2335 are the two fire standards that come up for plastic pallets. Both are tests a named model passes or fails, and a listing never transfers to another model.
Why it comes up
Sprinklers are designed around what is stored and what it sits on. The ICC Building Safety Journal explains that a plastic pallet can change the hazard classification of a storage arrangement, and that unlisted plastic can push a designer to a more demanding sprinkler scheme. A fire listing is how a maker shows a model behaves in a test.
FreightWaves reported on a pallet pooler's plastic pallets receiving fire approval, a sign of how much the storage market cares. The owner of a rack full of pallets asks for the listing because the insurer and the fire engineer do.
Two standards, two bodies
| Standard | What it is | What you ask for |
|---|---|---|
| FM 4996 | A classification standard for plastic pallets from FM Approvals | The approval for the exact model, its number and its date |
| UL 2335 | A fire test standard for storage pallets | The test report for the exact model and the arrangement tested |
Some makers hold one, some both, some neither. A pallet that is listed to one is not thereby listed to the other. Ask which your insurer and your fire engineer accept before you choose.
Rules that save a mistake
- A listing belongs to one model. A lookalike from another maker, or the same maker's other model, is not covered.
- Colour, recycled content and revisions can matter. Ask whether they change the listing.
- The listing covers a tested arrangement, not every stack height.
- This site does not claim that any pallet is fire rated. We tell you what to ask.
A stack worked out
Take a stackable rated 15,000 lb static. The bottom pallet carries the pallets above it, so with each loaded pallet weighing 2,635 lb it can hold 5 above, a stack of 6. With 6,677 lb per pallet it can hold 2 above. This is a ceiling on a flat floor for a still stack, not a promise for a stack that moves or waits.
| Loaded pallet, lb | Pallets above the bottom | Stack height | Load on the bottom pallet, lb |
|---|---|---|---|
| 2,635 | 5 | 6 | 13,175 |
| 3,142 | 4 | 5 | 12,568 |
| 3,649 | 4 | 5 | 14,596 |
| 4,156 | 3 | 4 | 12,468 |
| 4,663 | 3 | 4 | 13,989 |
| 5,670 | 2 | 3 | 11,340 |
| 6,677 | 2 | 3 | 13,354 |
What the document does not tell you
A listing says how a pallet behaved in one test arrangement. It does not say the pallet is safe in every building, and it says nothing about strength, nesting or food contact. Treat it as one input to the sprinkler design and keep it separate from the ratings that govern loads.
A note on this page
Two standards, two testing bodies, two documents: a buyer asked for one will sometimes be handed the other. Check the number printed at the top of the paper before it is filed, and confirm the pallet model named in it matches the moulded mark on the deck.
Words on this page
- GMA pallet
- The 48 by 40 inch North American standard, named for the Grocery Manufacturers Association that popularised it.
- HDPE
- High-density polyethylene, a tough resin used in many plastic pallets, valued for strength against its weight.
- FM Approvals
- A testing and certification body whose classifications insurers and sprinkler designers read.
- Nest ratio
- How many empty pallets fit in the height of one: pallet height divided by nest increment.
- Cube utilisation
- How well loaded freight fills the volume of a trailer or container. Taller or wider-than-floor pallets waste cube.
- Nest increment
- The extra height each additional empty pallet adds to a nested stack, measured in inches. A small increment means a short stack.
- Closed loop
- A route where pallets return to the sender after delivery, so the empty trip is a standing cost.
- Pallet pooling
- A rental model where a company owns the pallets and moves them between customers, instead of each customer buying its own.
Tell us the footprint and how many stacks you move.
We work out the empty trailer, then take the request for a load.