Use of Aluminum as an ASME Code Material for Shielding and Criticality Safety Applications

A Type-B radioactive material (RAM) packaging design is required to demonstrate compliance with the performance requirements of Title 10 of the Code of Federal Regulations (CFR), 10 CFR 71.55 and 71.59 for criticality safety. The Type-B Packaging may use packaging structures, systems, and components (SSCs) that perform safety functions. NUREG/CR-3854 defines Component Safety Groups (CSG) that require demonstration of adequate performance of their materials of construction. One CSG consists of SSCs that perform \"Other Safety\" functions. The American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (BPVC) defines the design and acceptance criteria applicable to the fabrication of SSCs. SSCs that perform \"Other Safety\" functions are required to meet Section VIII, Division l or Section III, Subsection NF. SSCs that perform \"Criticality\" safety functions must meet Section III, Subsection NG. These “Criticality” and “Other Safety” SSCs are often made of aluminum. The National Nuclear Security Administration (NNSA) Office of Packaging and Transportation (OPT) has developed Interim Guidance 2015-1: Process for Demonstrating Acceptable Structural Performance of Packaging Structures, Systems, and Components (SSCs) that Perform Nuclear Criticality Control or Other Safety Functions Fabricated from Materials Other than those Specified in ASME Boiler and Pressure Vessel Code. The paper discusses how Interim Guidance 2015-1 was used to demonstrate that aluminum can be used as a material of construction to fabricate SSCs per the applicable ASME BPVC sections.