Solid wood packaging carries pests. Larvae bore into timber, survive a sea voyage inside a pallet, and emerge into a country with no natural predator for them. That is how the emerald ash borer and the pine wood nematode crossed oceans, and it is why ISPM 15 exists.
ISPM 15 is an International Standard for Phytosanitary Measures issued under the International Plant Protection Convention. The current text is the 2018 revision, with the annexes covering the mark and treatments last revised in 2019. It is adopted by well over 80 countries, and it is enforced at the border by plant health inspectors who have the power to refuse entry to the whole consignment.
What is covered, and what is not
The rule applies to coniferous and non-coniferous raw wood packaging over 6mm thick. That is pallets, crates, cases, drums, skids, bracing, blocks and dunnage.
Exempt, because manufacturing already destroys any pest:
- Processed wood: plywood, oriented strand board, particle board, veneer, and anything made with glue, heat and pressure
- Wood 6mm thick or less
- Sawdust, wood wool and shavings
- Barrels for wine and spirits that were heated during manufacture
- Gift boxes of wine, cigars and similar, if made from wood processed or manufactured to be pest free
The two treatments
- HT, heat treatment. The wood must reach a minimum core temperature of 56C for at least 30 continuous minutes. This is by far the most common route, and the kiln operator certifies it.
- MB, methyl bromide fumigation. Still permitted under the standard but being withdrawn in practice. Methyl bromide is an ozone depleting substance under the Montreal Protocol, and a growing list of countries, including the whole European Union, no longer accept MB treated wood packaging at all.
Dielectric heating (DH) is also recognised. If you have any choice, specify HT. An MB stamp is a shipment that some destinations will refuse on the mark alone.
Reading the IPPC mark
The mark is often called the wheat stamp, after the symbol on the left. It must be legible, permanent, not red or orange, and applied to at least two opposite sides of the item. It carries:
- The IPPC symbol
- The ISO two letter country code, for example GB, CN, MY
- A unique producer or treatment provider code issued by that country's plant health authority
- The treatment code: HT, MB or DH
- Optionally DB for debarked
Notice what is not on it: a date. The mark does not expire. A pallet treated eight years ago is still compliant, provided the wood has not been repaired with untreated timber since.
Why shipments actually get rejected
Rarely because someone bought untreated pallets. Almost always one of these:
- Dunnage. The pallets were certified, then the loading crew cut some scrap timber to brace the load in the container. That scrap is regulated wood packaging and it has no mark. This is the single most common failure.
- Repairs. A broken board replaced with untreated wood invalidates the pallet unless it is re-treated and re-marked. A repaired pallet must carry the mark of whoever repaired it.
- Illegible marks. Painted over, sanded off, or stamped on a face that ended up inside the stack.
- Bark. Some countries require debarked wood and inspect for it.
- Live pests found on inspection. A correct mark does not save a consignment where an inspector finds insects.
What happens when it fails
The options are set by the importing country and none of them are cheap: treatment at the port at your cost, re-packing under supervision, re-export of the entire consignment, or destruction. Australia, the United States, China and the European Union all enforce actively, and in several markets the penalty attaches to the importer, who will pass it back to you.
The cargo itself is usually fine. You are paying to fix the wood it is sitting on.
Practical steps
- Write ISPM 15 compliance into the purchase order with your supplier, and ask for a photograph of the marked pallet before shipment.
- Tell whoever stuffs the container that dunnage counts. Use marked timber, or use non-wood alternatives such as dunnage bags, honeycomb board and plastic bracing.
- Consider presswood or plastic pallets for problem lanes. Presswood is a processed wood product and is outside the standard entirely.
- Keep the treatment certificate where you can produce it, even though the mark is what is inspected.
For the rest of the packing decision, see export packaging and palletisation and cargo securing inside the container.
General guidance. Requirements vary by importing country and change. Check the destination's plant health authority before shipping, particularly for Australia, New Zealand and China, which each add national conditions on top of ISPM 15.
