ISPM 15 heat treatment versus drying

Drying reduces moisture for a commercial handling or storage objective. ISPM 15 treatment is a phytosanitary measure intended to reduce the international spread of pests in raw-wood packaging. A dry-looking board, weathered colour or a kiln-dried description cannot establish that a pallet has undergone an approved treatment.

A kiln can be used for conventional heat treatment, but its cycle must meet the approved schedule, with appropriate monitoring and authorised marking. Air temperature alone is not the requirement.

For conventional steam or dry-kiln heat-chamber treatment, ISPM 15 Annex 1 requires at least 56°C for 30 continuous minutes throughout the entire wood profile, including the core. Treatment schedules and the monitoring arrangements are specified or approved by the national plant protection organisation. This is not a DIY heating instruction.

Other approved measures have different conditions. Dielectric heating uses the DH treatment code; fumigation measures listed in the standard also have their own schedules and restrictions. The 56°C/30-minute schedule must not be described as the rule for every ISPM 15 treatment.

HT is a treatment identifier, not a load rating, moisture specification or promise that timber can never acquire pests again. Inspect current condition and cleanliness and agree handling suitability separately. If your customer needs a particular dryness or storage condition, add it to the brief rather than infer it from HT.

We can supply used pallets already heat-treated and correctly marked for ISPM 15, or arrange treatment through a registered partner. Tell us the destination, treatment and marking requirement, customer restrictions and shipping deadline. The route is quoted against specification, availability and destination requirements.

For an already-marked used pallet order, specify footprint, construction, condition and shipment requirements. Where partner treatment is needed, allow time for assessment, treatment arrangements and delivery; the lead time is confirmed in the quote. Keep moisture requirements and export treatment requirements as separate lines in the order.

Based on the IPPC ISPM 15 standard (sections 2.1, 4.3 and Annexes 1–2), GOV.UK Forestry Commission guidance and the Defra wood-packaging page, updated 16 September 2026. Follow the linked official sources and reconfirm requirements before shipment.