IMPACT OF THE NEW IAEA REGULATIONS ON THE TRANSPORT OF UF6 IN 48Y CYLINDERS

The transport of uranium hexafluoride (UF 6) is chiefly regulated taking into account its radioactive risk. The 48 Y cylinders containing uranium hexafluoride with an enrichment lower than 1%, have mainly to prevent the \"loss or dispersal of the radioactive contents\" when subjected to a 0.60 m drop. In 1984, the Mont-Louis ship, transporting 48Y cylinders, sank in the North Sea. All the packages were recovered with no release of contents, and therefore with no chemical or radiological contamination. However, this led the international transport community to question the adequacy of the regulations relevant to uranium hexafluoride, and prompted the IAEA and the Member States to upgrade the existing regulations applying to the transport of UF6. Concerning 48 Y cylinders, a unilateral approval will be granted after demonstrating their ability to withstand without rupture a 800°C frre test for 30 min~tes. Neither the FrancoJapanese TENERIFE programme, nor other experiments, have yet allowed to guarantee that it is the case. Various potential solutions, such as new cylinders, overpacks, transport frames, end covers, thennal blankets, intumescent paint are described, with a brief assessment of their respective benefits and drawbacks. The assessment of the various solutions will take into account the direct cost of the equipment, but also expenses covering its design and licensing, as well as a possible increase of the operational costs resulting from the preparation of the cylinder, its transport, and the inventory management and maintenance of this new equipment.