Investigation of Thermal Response of Radioactive Material Transportation Casks to Open Pool Fire Test Simulations

Hazards in the transportation industry from truck and rail shipments can result in accidents involving fire. Fire is a concern in the transportation of radioactive material, specifically, that transportation accidents can cause ignition of flammable materials that could fully engulf a transportation package, increasing the potential for release of radioactive material. Title 10 of the Code of Federal Regulations Part 71 section 73(c)(4), (10 CFR 71.73(c)(4)) delineates that transportation packages designed to ship radioactive material and that are subject to accident conditions must be designed to resist a consuming fire of a duration of 30 minutes in order to protect the contents of the package and prevent release of radioactive material to the environment. Testing and analysis of the performance of a transportation package design is therefore essential to ensuring that a package can survive a fire accident and will not exceed radioactivity release limits established by the NRC. Staff of the NRC Spent Fuel Project Office visited Sandia National Labs in Albuquerque, New Mexico, to observe an open pool fire test of a large steel calorimeter, similar in size to a typical transportation cask for a single assembly of spent nuclear fuel. The test was conducted to verify the Cask Analysis Fire Environment (CAFE) computer code being developed by Sandia for the analysis of radioactive material transportation package thermal performance. The Sandia test was conducted in accordance with the thermal requirements outlined in 10 CFR 71.73. This paper will discuss the staff’s plans to use the CAFE code, in conjunction with the finite element analysis program ANSYS, to conduct several investigations of the thermal response of shipping cask designs to open pool fire testing. Several variables for testing of casks will be investigated in the staff’s efforts.