Criticality evaluation of Oak Ridge model DT-21 packaging with uranium metal

Shipments of fissile and radioactive materials are made in packaging that is designed, fabricated, assembled, tested, procured, used, and maintained in accordance with the provisions cited below to protect the environment and the health and safety of the public and workers. This paper summarizes the criticality safety analysis of the packaging that was prepared in accordance with U.S. Department of Energy Order 5610.1 for the Martin Marietta Energy Systems, Inc., Oak Ridge Y-12 Plant, model DT-21 packaging for uranium metal. The DT-21 packaging with uranium metal meets the requirements of 10CFR71 of the Code of Federal Regulations and 49CFR100-178. The uranium metal loading configurations, shapes, and masses analyzed demonstrate a safe loading limit of 18 kg of 235U with a total uranium mass limit of 30 kg