When shipping goods internationally using wood packaging materials, compliance with ISPM-15 (International Standards for Phytosanitary Measures No. 15) is mandatory. This international regulation, adopted by over 180 countries, requires that all wood packaging materials be treated to eliminate pests that could hitch a ride across borders and devastate foreign ecosystems.
ISPM-15 approves two primary treatment methods: heat treatment (HT) and methyl bromide fumigation (MB). While both methods achieve the same goal of eliminating wood-boring insects, bark beetles, and other pests, they differ dramatically in their process, environmental impact, cost, and global acceptance. Understanding these differences is crucial for any business involved in international shipping.
Heat Treatment (HT): The Preferred Method
Heat treatment involves placing wood packaging materials in a specially designed kiln or heat chamber and raising the core temperature of the wood to at least 56 degrees Celsius (132.8 degrees Fahrenheit) for a minimum of 30 minutes. This temperature is sufficient to kill all life stages of wood-boring insects, nematodes, and other organisms that pose phytosanitary risks.
The heat treatment process is entirely chemical-free, making it the environmentally preferred option. No toxic substances are applied to the wood, no hazardous residues remain, and no harmful emissions are released into the atmosphere. Workers in the treatment facility face no chemical exposure risks, and the treated pallets are safe to handle immediately after cooling.
Heat treatment is universally accepted by all ISPM-15 signatory countries without exception. This makes HT-stamped pallets the safest choice for international shipping, as you will never encounter regulatory issues at any port of entry worldwide. The HT stamp on the pallet, along with the facility registration number and country code, serves as proof of compliant treatment.
At Fresno Pallets, all of our heat treatment is performed in our own certified facility, ensuring quality control and rapid turnaround. We can treat pallets within 24-48 hours, making it easy to meet tight shipping deadlines.
Methyl Bromide Fumigation (MB): The Legacy Method
Methyl bromide fumigation involves exposing wood packaging materials to methyl bromide gas, a broad-spectrum pesticide that penetrates the wood and kills all biological organisms. The treatment requires a specific gas concentration maintained for a minimum exposure period, typically 16-24 hours depending on wood temperature and thickness.
While effective at eliminating pests, methyl bromide is a potent ozone-depleting substance classified under the Montreal Protocol. Its use has been progressively restricted worldwide, and many countries have banned or severely restricted methyl bromide for phytosanitary purposes. The European Union, Canada, Australia, China, and numerous other major trading partners no longer accept MB-treated wood packaging.
The declining acceptance of methyl bromide makes it an increasingly risky choice for exporters. A shipment arriving at a port that does not accept MB treatment may be refused entry, quarantined, or destroyed, resulting in significant financial losses and supply chain disruptions. For this reason, heat treatment has become the overwhelmingly preferred method for the vast majority of international shippers.
Side-by-Side Comparison
From an environmental standpoint, heat treatment is clearly superior. It produces no chemical residues, generates no ozone-depleting emissions, and poses no health risks to workers or end users. Methyl bromide, despite its effectiveness, contributes to ozone layer depletion and leaves chemical residues on the treated wood.
In terms of cost, heat treatment and methyl bromide fumigation are comparable for standard pallet volumes. However, the additional regulatory requirements, safety equipment, and restricted handling procedures associated with methyl bromide can increase the total cost of fumigation. Heat treatment facilities also benefit from lower ongoing operational costs since they do not need to purchase and store hazardous chemicals.
For processing time, methyl bromide fumigation historically had an advantage for very thick timber, as the gas can penetrate dense wood faster than heat. However, modern heat treatment kilns with improved air circulation and humidity control have largely closed this gap. For standard pallet lumber (typically 3/4" to 1.5" thick), both methods can be completed within a similar timeframe.
Our Recommendation
We strongly recommend heat treatment for all wood packaging materials destined for international shipment. It is universally accepted, environmentally responsible, chemical-free, and cost-competitive. There is simply no practical reason to choose methyl bromide fumigation when heat treatment offers equal or superior results without the environmental and regulatory baggage.
If you need ISPM-15 compliant pallets for your export shipments, Fresno Pallets offers certified heat treatment with fast turnaround times. Whether you need to treat new pallets, used pallets, or custom crating, our facility is equipped to handle orders of any size. Contact us to discuss your international shipping needs.