Heat-treated pallets for export
Heat treatment means the wood core reached 56 degrees Celsius for at least 30 minutes, and the pallet carries the IPPC mark to show it. It is what most export lanes ask for under ISPM 15.
What HT and ISPM 15 mean
ISPM 15 is the international standard for wood packaging material in international trade. The aim is to stop pests travelling in raw wood. It lets two treatments qualify a pallet: heat treatment and fumigation. The trade writes the first as HT, and you will see the letters on the mark. Heat treatment requires the wood core to reach at least 56 degrees Celsius (133 degrees Fahrenheit) for a minimum of 30 minutes.
A pallet also has to be debarked before treatment. Some bark is allowed to remain: pieces narrower than 3 centimeters, or wider pieces whose surface area is under 50 square centimeters. After treatment the pallet gets the stamp, which says who treated it and how. Reading the stamp takes it apart piece by piece.
When you actually need it
| Where the pallet is going | What to know | Next |
|---|---|---|
| Ontario, from the United States | Wood packaging from the continental US is currently exempt from the Canadian Food Inspection Agency's policy D-98-08, pending a phased move to full ISPM 15. That is a current rule, not a promise it will stay, and a customer can still ask for the stamp. | Pallets across the bridges |
| Overseas | Many importing countries apply ISPM 15 to the wood packaging that comes in. Check the importing country's rule for your lane. | Ask the carrier or the customer for the requirement in writing. |
| Inside the US | Not required for domestic moves. | A Grade A or Grade B pallet will do. |
Heat treatment is not a grade
Grade is about repairs. Heat treatment is a process. A new pallet can be heat treated, and so can a Combo, and each will carry the mark if it was treated and stamped. If a pallet was repaired after it was treated, ask whether the wood used in the repair is treated and marked too, and say so up front if your lane is strict.
Heat treatment does not stop mold
Heat-treated pallets loaded into trailer vans while still hot are susceptible to mold, because the warm wood and the closed van trap moisture. The wood is not immune afterward. Moisture below 20% will not support mold, mildew, decay or fungus, and even a slight air velocity of a few feet per second helps. Mold on pallets.
What to tell us
- The lane: Ontario, another country, or a customer's own rule.
- The size, and whether it is new or Combo. A 48 x 40 is the usual export footprint; sizes shows the rest.
- How many, and when. A single crate and a container of crates are different requests.
- Whether the customer needs the stamp to be legible and complete on both sides, and any paperwork that goes with it.
Whether a pallet is stamped depends on the stock. If you need the mark, say so in the request.
Questions about heat-treated pallets
What does the heat treatment do?
It raises the wood core to at least 56 °C and holds it there for a minimum of 30 minutes, which kills pests in the lumber.
Does heat treatment prevent mold?
No. Heat-treated pallets loaded into trailer vans while still hot are susceptible to mold, because treatment does not make wood immune.
Does the wood have to be debarked?
Yes. Wood packaging must be debarked before heat treatment or fumigation. Allowed bark must be less than 3 cm wide, or if wider, under 50 square cm in surface area.
Do I need them for Ontario?
Wood packaging from the continental US is currently exempt from CFIA policy D-98-08 pending a phased move to full ISPM 15. Check the lane.
Where the stamp sits
The mark is burned or stamped onto a visible face of the pallet, usually on a block or a stringer end. It carries the IPPC symbol, a country code, a producer number and a treatment code. The stamp guide shows how to read it. A pallet without a clear mark may be refused at a border, so a legible mark is part of what you are buying.
Used stamped stock
A used pallet can be heat-treated and stamped. It can also carry a stamp from its first life that is no longer legible. Ask for a photograph of the mark before agreeing to a count.
Planning a lane
Name the lane
Where the freight enters Canada and what the receiver requires.
Choose the stock
Heat-treated and stamped, in the size your load uses.
Keep it separate
Mark and store stamped pallets apart from unstamped ones, so they do not mix on the dock.
Heat-treated against fumigated
ISPM 15 allows two treatments: heat and fumigation. Heat treatment is the one covered here. Fumigated wood carries a different treatment code in its mark, and some receivers refuse it. If your freight crosses a border, ask the receiver which treatment it accepts before buying.
Storing treated stock
Treated lumber is dry when it leaves the kiln, and it stays that way only if it is kept dry. Stack it off the floor, under a roof, with air moving through the stack. Wood below 20% moisture will not support mold, mildew, decay or fungus, so a month in a dry shed costs nothing, while a month in the rain can ruin the batch.
Asking for the paperwork
A producer of treated pallets can supply a certificate or a record of the treatment batch. If a receiver has asked for proof, request it with the order. Keep a copy with the shipment, because a border officer may ask for it.
Treated pallets cost more than untreated ones, so use them where the lane requires it and not as a habit.
Which pallets get stamped
New pallets are often treated at the mill before they are assembled, while used pallets are treated afterward in a kiln. In both cases the mark goes on a visible face. A new treated pallet carries one mark from the first life; a repaired one may carry a second. Ask which applies to the stock you are offered, and check the mark yourself on a sample.
Quality checks on arrival
Sample a few pallets from different layers. Confirm the mark is legible, the bark limits are met, and the wood is dry to the touch. A pallet that is damp or smells musty after treatment may have been loaded hot into a closed van. Photograph any problem and note it on the delivery slip before the driver leaves.
Used and treated
Treated used stock exists, but is rarer than untreated. Allow extra time to find a lot that matches your size and count.
Make the request
Heat-treated stock: name the lane or the customer asking for the mark, plus size and count.