ISPM 15

The international standard for treating and marking wood packaging to stop pests spreading in trade.

Last reviewed October 27, 2026 by repallet.org editors.

ISPM 15, the International Standard for Phytosanitary Measures No. 15, is the IPPC standard for wood packaging material in international trade. Wood pallets and crates crossing borders must be treated by an approved method and marked.

The mark carries a treatment code: HT for heat treatment, MB for methyl bromide fumigation, and others in later revisions. Heat treatment requires the whole profile of the wood, including its core, to reach at least 56 °C for 30 continuous minutes.

For reuse and safety the treatment code is the part that matters: HT is a heat treatment, MB a fumigant. This site explains what that means for reuse; for every character in the mark, use the stamp decoder at epalrecycling.com.

Domestic pallets that never cross a border may carry no ISPM 15 mark at all.

Related

• HT pallets: what heat treated means and what it doesn't
• MB pallets: methyl bromide and what it means for reuse
• Heat treatment (HT)
• Methyl bromide (MB)
• Quarantine and preshipment (QPS)
• All terms