The fumigated packaging materials are treated in such a way that all vermin has been exterminated. They will also bear a stamp and be accompanied by a certificate.
A fumigation certificate is issued only in combination with a correct invoice and Bill of Lading instructions. Without the correct certificates and packaging materials you may get into major trouble, and face high additional storage costs or the confiscation of goods.
All extermination costs are passed back to and are payable by the shipper. Due to vermin that may penetrate wood, many countries demand fumigated packaging materials for imported goods.