Abstract: Criticality safety needs to be considered carefully during the transport of intact nuclear fuel assemblies. Several factors should be taken in to account, such as package arrays, container damages under hypothetical accident condition and water moderation conditions. In this work, criticality safety analysis has been carried out for a Westinghouse XL shipping container loaded with AP1000 fuel assemblies. The fuel assembly and transport container have been modeled and simulated using the MCNP code. The results of MCNP show that the Westinghouse XL package is subcritical, if the number of packages meets the requirements in the approval of the competent authority.

Key words: AP1000 fuel assembly, transport package, criticality safety analysis