Reading a pallet stamp
The stamp on a wood pallet says whether it may cross a border. It carries the IPPC mark, a country code, the producer’s number and a treatment code: HT for heat treated, MB for methyl bromide, DB for debarked on older marks. A pallet that stays in the United States does not need one.
What is on the stamp
| Part | What it tells you |
|---|---|
| IPPC mark | The wood packaging meets the international standard |
| Country code | Where the pallet was treated |
| Producer number | Which facility treated it |
| HT | Heat treated: the core reached at least 56 °C for at least 30 minutes |
| MB | Fumigated with methyl bromide |
| DB | Debarked, on older marks |
ISPM 15 regulates wood packaging material in international trade (Wikipedia).
Why it exists
The International Plant Protection Convention requires pallets that cross borders to be made of material that cannot carry invasive insects or plant diseases. ISPM 15 is the standard that sets the treatments. Wood must be debarked before heat treatment or fumigation. Bark that remains must be under 3 cm wide, or if wider, under 50 square cm in surface area.
When you need one
- Export by container or crate. The stamp is required. Ask for heat-treated pallets.
- Domestic freight. Not required.
- Into Canada from the continental United States. Wood packaging is currently exempt from CFIA policy D-98-08, pending a phased move to full ISPM 15 implementation. Check the current rule before shipping.
What heat treatment does not do
It does not make wood immune to mold. A heat-treated pallet loaded into a trailer while still hot can grow mold; see the mold guide. It also does not mean the pallet is clean or Grade A.
Reading a stamp left to right
- The symbolA stylized wheat ear with the letters IPPC, showing the pallet meets the international standard.
- The countryA two-letter code for the country where treatment took place.
- The producerA number assigned to the facility that treated the wood.
- The treatmentHT for heat, MB for methyl bromide.
Why stamps get refused
A stamp can be refused for several reasons. It may be smudged or cut off by a repair. It may be missing a part, such as the producer number. The wood may show bark above the allowed limit. Or the treatment code may not match what the importing country accepts.
Inspectors act on the pallet, not the paperwork. If the mark is not legible on the pallet itself, the load can be held. Check marks on the side that faces the aisle, before the load is wrapped.
Re-treatment and repair
A pallet that is repaired after treatment should be re-marked or re-treated if the repair is made with untreated wood. A pallet with a fresh replacement board and no new stamp raises questions at inspection. When you buy for export, ask whether the pallets were repaired and when, and look at the replacement boards themselves.
A worked example
Suppose a container of machine parts is leaving for Rotterdam. The shipper orders twelve pallets, and the exporter’s agent asks for ISPM 15 compliance. You inspect the pallets, find the wheat-ear symbol, the country code US, a producer number and HT on every end block, and confirm no bark beyond the limit. The load can go.
When a stamp is not enough
A legible stamp proves a treatment standard, not the condition of the lumber. A heat-treated pallet can still be cracked, damp or contaminated, so inspect boards as well as marks.
Stamp placement
The mark usually sits on two opposite sides of a pallet, on a stringer or block, where it stays legible after repairs. Look at both sides before deciding a pallet is unmarked.
Questions
- What does HT mean on a pallet?
- The pallet was heat treated so the wood core reached at least 56 °C for at least 30 minutes.
- Do I need a stamp on pallets for domestic shipping?
- No. The stamp is for pallets that cross borders.
- What does the wheat ear mean?
- It is the IPPC symbol, which shows the pallet was treated to the international standard.