material (such as wood). ISO Technical Committee 51: Pallets for unit load method of materials handling ISO TC 51 states its scope of work entailing the "standardization of pallets in general use in the form of platforms or trays on which goods may be packed to form unit loads for handling by mechanical devices". The Technical Committee works in conjunction with other Technical Committees focused on transportation infrastructure to develop interrelated standards. TC 51 is responsible for developing ISO Standard 6780: Flat pallets for intercontinental materials handling—Principal dimensions and tolerances as well as sixteen other standards related to pallet construction and testing. National Wood Pallet and Container Association The National Wood Pallet and Container Association (NWPCA) is a trade organization based in the United States representing the interests of wood pallet and container manufacturers. U.S. Department of Defense, Department of the Navy, Naval Sea Systems Command This organization maintains MIL-STD-1660, the standard description of palletized unit loads for the U.S. Military and some allies. DOD Unit loads generally use pallets, are less than , weatherproof, and stack high. They often use steel pallets, steel straps with notched seals, outdoor plywood, and plastic film. The standard describes tests for stacking, transport, sling, forklift and pallet jack, impact, drop tests, tip, water-retention, and disassembly. European Committee for Standardization (Comité Européen de Normalisation) In addition to the other standards it publishes, the European Committee for Standardization, also known as the Comité Européen de Normalisation (CEN), produces standards for pallets. While the standards are voluntary in nature, many companies and organizations involved in transportation have adopted them. The major standard for pallets produced by CEN is ICS: 55.180.20 General purpose pallets Phytosanitary compliance Due to the International Plant Protection Convention (abbreviated IPPC), most pallets shipped across national borders must be made of materials that are incapable of being a carrier of invasive species of insects and plant diseases. The standards for these pallets are specified in ISPM 15. Pallets made of raw, untreated wood are not compliant with ISPM 15. To be compliant the pallets (or other wood packaging material) must meet debarked standards, and must be treated by either of the following means under the supervision of an approved agency: Heat treatment The wood must be heated to achieve a minimum core temperature of for at least 30 minutes. Pallets treated using this method bear the initials HT near the IPPC logo. Chemical