Heat treated pallets and ISPM 15
Most countries only accept solid wood pallets and crates that meet ISPM 15: the wood is heat treated (core at least 56 °C for 30 minutes) or fumigated, then stamped with the IPPC mark, country code, producer number and treatment code such as HT. Plastic, plywood, OSB and presswood pallets are exempt.
What ISPM 15 is
ISPM 15 is an international standard from the International Plant Protection Convention (IPPC) that stops wood-boring pests travelling in packaging. Most trading countries, including the US, Canada, the EU, the UK, China and Australia, require it for imports.
What must be treated
- Pallets, skids, crates, boxes and cable drums made of solid wood.
- Dunnage: wood used to brace or block cargo in containers.
- Wood packaging that has been repaired or reused must still carry valid marks.
What is exempt
- Processed wood: plywood, OSB, particle board, fibreboard and presswood pallets.
- Wood 6 mm thick or less, and shavings, sawdust or wood wool.
- Plastic, metal and paper pallets.
- Barrels for wine and spirits that were heated in manufacture.
Reading the ISPM 15 stamp
| Part of the mark | Meaning |
|---|---|
| IPPC wheat-ear logo | The mark is an official ISPM 15 mark |
| Country code, e.g. CN, US, DE | Country where the wood was treated |
| Producer or treatment number | The registered company that treated or made it |
| HT | Heat treatment, core 56 °C for 30 minutes |
| MB | Methyl bromide fumigation, restricted or banned in many countries |
| DH | Dielectric heating, an approved alternative |
The mark must be legible and permanent, on at least two opposite sides of the pallet or crate. A handwritten 'HT' does not count.
If wood packaging is not compliant
Customs or plant health officers can order the packaging to be treated, removed and destroyed, or the whole shipment re-exported, and the importer pays. Live insects can trigger an inspection of later shipments from the same exporter.
Practical tips
- Ask your pallet supplier for stamped HT pallets for any export, even if the destination seems relaxed.
- Check dunnage and bracing timber too; it is often forgotten.
- Consider plastic or presswood pallets for air freight: lighter and exempt.
- Mention compliant wood packaging on the packing list if the buyer asks.
Sources
Tools used in this guide
Related guides
Common questions
What does HT mean on a pallet?
Heat treated: the wood was heated until its core reached at least 56 °C for 30 minutes under ISPM 15.
Do plastic pallets need ISPM 15?
No. ISPM 15 applies to solid wood packaging; plastic, metal and processed wood such as plywood are exempt.
Do I need heat treated pallets for export?
For most countries yes, if the pallets are solid wood. Untreated pallets can be refused or destroyed.
What is the difference between HT and MB pallets?
HT pallets are heat treated; MB pallets were fumigated with methyl bromide, which many countries restrict or ban.