US-based NAC International has received approval from the US Nuclear Regulatory Commission (NRC) for its patented OPTIMUS-L packaging system to transport high activity radioactive sources. This enhances the capabilities of NAC’s OPTIMUS systems, which are fabricated and licensed to transport a range of radioactive materials from HALEU (high assay low-enriched uranium) fuel to used fuel from nuclear power plants.
Mike McMahon, Vice President of Transportation & Strategic Projects at NAC International, said: “The OPTIMUS-L system’s expanded capacity to transport high-activity sources in a wide range of environments opens the door to provide more cost-effective transportation and disposal options for our customers.”
The OPTIMUS-L system is now licensed to carry a broader range of high-activity contents, including sealed sources such as caesium-137 and cobalt-60, widely used in medical, industrial, and research applications. In response to industry demand for a compact, lightweight, and modular Type B(U)F package, NAC enhanced the system’s capabilities with a novel licensing approach that takes into account the shielding provided by sealed source devices themselves.
This innovation enables OPTIMUS-L to safely transport high activity sources without requiring additional external shielding. This is ideal for use in constrained environments such as hospital loading docks, laboratories, and urban facilities without extensive overhead lifting infrastructure. NAC continues to expand the OPTIMUS-L licensing basis to include additional sealed source configurations and shielded irradiator
The enhanced OPTIMUS-L system accommodates up to 2,800 curies of caesium-137 and 5 curies of cobalt-60, with a thermal load of approximately 13.5 watts, well within the system’s 50-watt limit. These capabilities are validated through rigorous structural, thermal, and shielding analyses, ensuring full compliance with NRC safety requirements under both normal transportation conditions and hypothetical accident conditions.
NAC’s OPTIMUS Type B systems are designed for maximum adaptability to transport a wide range of radioactive materials. The OPTIMUS-H licence accommodates high activity contents such as used nuclear fuel and remote-handled transuranic waste. OPTIMUS-L can be used for lower activity contents such as contact-handled transuranic waste, High-Assay Low-Enriched Uranium (HALEU), and mixed low-level radioactive waste.
