Of all the ways an import container can go wrong, wood packaging is the one importers understand least and pay for most. The cargo can be perfectly compliant, the entry perfectly filed — and a single untreated pallet inside the container can trigger an enforcement action that ends with the whole shipment being re-exported at your expense.
This is a practical explanation of ISPM 15, the international standard governing wood packaging in trade, and what to do about it.
What ISPM 15 is
ISPM 15 is an international phytosanitary standard developed under the International Plant Protection Convention. Its purpose is to stop wood-boring pests — beetles, borers, nematodes — from traveling the world inside pallets and crates. The emerald ash borer and the Asian longhorned beetle both arrived in North America this way, and the economic damage runs into billions.
The standard applies to wood packaging material (WPM): pallets, crates, dunnage, blocking and bracing, skids, drums and spools made of raw wood. It applies to the packaging, not the cargo. A container of machinery bolted to an untreated wooden skid is non-compliant even though the machinery itself has nothing to do with plant health.
What compliant wood looks like
Compliant WPM must be treated by one of the approved methods and then marked. The two common treatments are:
- Heat treatment (HT) — heating the wood to a core temperature of 56°C for at least 30 minutes. This is the dominant method.
- Methyl bromide fumigation (MB) — still recognized under the standard, but restricted or prohibited in a number of countries for environmental reasons.
The mark — usually branded or stencilled onto the wood — carries the IPPC symbol, a country code, a unique producer or treatment provider code, and the treatment abbreviation (HT or MB). It should be legible, permanent, and applied on at least two opposite sides of the item.
What is exempt
Manufactured wood products are outside the standard, because the manufacturing process already kills pests. That includes plywood, oriented strand board, particleboard, veneer, and wood that has been produced using glue, heat and pressure. Wood thinner than 6mm is also generally exempt. Paper, plastic and metal packaging obviously don’t apply.
What actually happens when WPM is non-compliant
This is where it gets expensive. Unlike most import problems, a WPM violation is generally not fixable at the border in the United States. Under CBP and USDA enforcement policy, non-compliant wood packaging is typically subject to immediate re-export of the WPM — and because separating a pallet from the cargo it carries usually isn’t practical inside a sealed container, that often means the entire shipment goes back.
The costs compound quickly:
- Return ocean freight, at your expense.
- Demurrage accruing at the terminal the entire time the situation is being resolved. Our demurrage explainer covers how fast that adds up.
- Per diem on the container.
- Penalties, which escalate for repeat violations at the same importer.
- Loss of the goods’ selling season entirely.
Repeat offenders also attract elevated inspection rates, which means more customs exams across all your future shipments — a slow, permanent tax on your supply chain.
Where violations come from
Almost never from the importer. Almost always from a supplier or their packer swapping in whatever pallet was on the floor that day. The recurring failure modes:
- Mixed loads. Nine compliant pallets and one that isn’t. The one is enough.
- Dunnage and bracing. Everyone remembers the pallets. Nobody remembers the untreated 2×4 the packer used to keep the load from shifting. This is the single most common source of violations.
- Illegible or fraudulent marks. A stamp that’s smudged, painted over, or applied by a provider not authorized in that country.
- Repaired pallets. A compliant pallet repaired with an untreated board becomes non-compliant, and requires re-treatment and re-marking.
- Bark. Wood must be debarked under the standard; visible bark is a red flag to an inspector even when the mark is present.
How to prevent it
- Put it in the purchase order, not just the contract. A clause requiring ISPM 15 compliant WPM including all dunnage, bracing and blocking, with legible marks — stated on every PO, in the supplier’s language.
- Ask for photographs of the loaded container before the doors close. Cheap, fast, and it catches the untreated brace. Photographs showing the IPPC mark on each pallet are better still.
- Specify alternatives where practical. Plastic pallets, presswood pallets and corrugated solutions are exempt from the standard entirely. For high-value or high-frequency lanes, this removes the risk permanently.
- Audit new suppliers on the first two or three shipments. Most violations come from new relationships or new packing subcontractors.
- Brief your customs broker if you have any doubt about a shipment, so the entry is handled with that in mind.
Rules and enforcement policy change, and requirements differ by destination country. Confirm current requirements with a licensed customs broker or the relevant agency — nothing here is customs or legal advice.
The drayage angle
If a WPM issue surfaces, the practical problem becomes a storage problem: a container you can’t clear, sitting on a terminal clock. The mitigations are the same as for any hold — know your last free day, and if the container is releasable to a bonded facility or an off-dock yard while the matter is resolved, moving it there costs far less than terminal demurrage.
For shipments where the cargo is fine but the packaging isn’t, transloading at a container freight station — restacking onto compliant pallets under the appropriate supervision — is sometimes part of the resolution, though whether that’s permitted depends entirely on the enforcement posture in the specific case. Your broker directs that decision, not your trucker.
If you’re dealing with a held container at PortMiami or Port Everglades and need it moved the moment it’s released, contact our team.
Frequently asked questions
Does ISPM 15 apply to plywood pallets?
Generally no. Plywood, OSB, particleboard, veneer and similar manufactured wood products are considered processed sufficiently to eliminate pest risk and fall outside the standard. Solid raw wood — including boards used as dunnage or bracing — is what the standard covers.
What happens if one pallet in my container isn’t ISPM 15 compliant?
Non-compliant wood packaging is typically subject to immediate re-export, and because separating it from the cargo inside a sealed container is usually impractical, the whole shipment often goes back. Costs include return freight, demurrage, per diem and potential penalties, with repeat violations attracting higher inspection rates.
Does the IPPC mark need to be on every pallet?
Yes — each regulated wood packaging item needs its own mark, applied legibly and permanently on at least two opposite sides. That includes dunnage and bracing, which is where most importers get caught out.