01Still valid, still a problem
Under ISPM-15 itself, `MB` remains a recognised treatment code. If you read only the standard, you would conclude that methyl bromide fumigation is a perfectly acceptable option.
Then you read the destination country's requirements. The European Union does not accept methyl bromide treated wood packaging. Neither do several other jurisdictions, and the list has grown steadily. A treatment can be valid under the international standard and refused at the border, and it is the border that decides whether your container moves.
02Why it is going away
Methyl bromide is an ozone-depleting substance controlled under the Montreal Protocol. Most uses were phased out years ago; quarantine and pre-shipment applications survived on an exemption that has been progressively narrowed.
There is also an occupational dimension. It is acutely toxic, it requires trained applicators and controlled facilities, and the handling requirements are substantially more onerous than putting wood in a hot room. Between the environmental pressure and the operational burden, the direction of travel has been obvious for a decade.
- Heat treatment core temperature — no chemistry involved
- 56°CHeat treatment core temperature — no chemistry involved
- Continuous hold required
- 30 minContinuous hold required
- Cost per pallet, roughly comparable to fumigation
- $1.10–1.90Cost per pallet, roughly comparable to fumigation
03What to do about inbound MB-marked wood
This is the practical question, because a lot of imported packaging still arrives carrying MB marks and it becomes your problem the moment you consider re-exporting on it.
- Domestic reuse is fine. ISPM-15 governs international movement. An MB-marked pallet moving within the United States raises no compliance question.
- Check before re-exporting. If the destination refuses MB, the pallet cannot go, mark or no mark.
- Re-treating is possible. A pallet can be heat treated and marked afresh. The old mark should be obliterated so there is no ambiguity at inspection.
- Do not assume the mark is the whole story. An MB-marked pallet that has since been repaired with untreated wood is non-compliant regardless of the treatment code.
04Our position
We do not fumigate and never have. Every pallet we treat goes through conventional heat treatment — 56°C core, 30 continuous minutes, probe-verified in the wood rather than the chamber air, logged against a charge number we keep for seven years.
That was not originally an environmental decision. It was a practical one: heat treatment is accepted everywhere, needs no licensed applicator, and has the side benefit of dropping moisture to 15–20%, which reduces weight and prevents mould in transit. The environmental argument arrived later and pointed the same way.
If a supplier offers you MB-treated pallets in 2025, that is information about the supplier as much as about the pallets. The full treatment picture is on the heat treatment service page, and the standard itself is covered in ISPM-15 explained.
