Reading the ISPM 15 stamp on a pallet

01 What the stamp holds

The mark has a symbol for the standard, a country code, a producer or facility number and a treatment code. The treatment code for heat treatment is HT. Methyl-bromide fumigation uses a different code and is treated separately in the standard.

02 How to check a pallet

1. Find the mark on the stringer or block, usually on two opposite sides.
2. Check that the treatment code reads HT.
3. Look for bark: the standard allows bark under 3 cm wide, or under 50 square cm if wider.
4. If there is no mark, the pallet is not ISPM 15 compliant, whatever it looks like.

03 How to tell if a pallet is heat treated

Only the mark proves it. Colour and smell do not. Some heat-treated pallets are bright and clean; others look as grey as any. The question people search, whether a pallet is heat treated, is answered by the stamp and nothing else.

04 When the mark is missing or worn

A worn mark cannot be trusted. If an inspector cannot read it, the pallet fails. Photograph the mark when the pallet is received, and replace a pallet whose mark is smudged by paint, a pallet label or a repair plate.

05 A mark is not a certificate

The stamp tells you who treated the wood and how. It is not a document, and some destinations also want an accompanying certificate. Ask the destination which they need.

06 Marks, codes and exemptions

The mark carries the IPPC symbol, a two-letter country code, the number of the producer or treatment provider and the treatment code, with the inspection agency's logo and certification number. HT is heat treatment; MB is methyl bromide fumigation, which the European Union banned from 19 March 2010. DUN marks treated dunnage. Packaging made of plastic, corrugated board, presswood, plywood or wood 6 mm thick or thinner is exempt, so those items carry no mark.

07 Which pallets carry no mark

Under the standard, plastic pallets, corrugated pallets, presswood or molded-wood pallets, composite wood blocks and plywood or oriented strand board carry no mark. Wine and spirits barrels are treated by the making process, and wood 6 mm or thinner is exempt. Dunnage that is treated may carry DUN. The mark is placed on two opposite sides of a treated pallet.

08 Country adoption dates

Countries adopted the standard on different dates: New Zealand in April 2003, India in November 2004, the European Union in March 2005, the United States and Canada in September 2005, and Australia on 1 July 2010 after a year of holding out for stricter bark limits.