Abstract
<title>Abstract</title> <p>Plasma-facing components (PFCs) that incorporate flowing liquid lithium surfaces are a promising technology because they can provide a renewable interface, modify recycling, support power exhaust, and potentially connect PFCs with fuel recovery. The deployment of liquid lithium PFC technology, however, is constrained by lithium chemical reactivity, fire and aerosol hazards, vacuum and inert gas operation, maintainability, and the need for rapid experimental iteration. Part 1 of this work develops a hazard-complexity metric for selecting secondary-containment architectures for flowing liquid-lithium systems. The framework is applied to six representative containment scenarios and to the Lithium Experimental Application Platform (LEAP), currently under construction at Princeton Plasma Physics Laboratory. LEAP uses a modular, room-sized argon glovebox as an inert secondary containment boundary for a staged flowing lithium program incorporating heating, diagnostics, magnetic field exposure, and future device interface capability. The analysis indicates that an inert, airtight secondary enclosure without scrubbers around an enclosed lithium loop provides a practical balance between hazard reduction and facility complexity for the present LEAP design requirements. This architecture offers a deployable pathway for lithium PFC development and a transferable design logic for other reactive or conductive liquid metal systems.</p>