Earthquake early warning (EEW) systems are used to provide timely alerts on ongoing earthquakes, which can facilitate important risk-mitigation actions before potentially damaging seismic waves reach target sites. A major shortcoming of existing EEW approaches is that the earthquake-related conditions for activating alerts are not generally defined according to a formal decision-support system (DSS) that accounts for possible risk-based consequences of triggering/not triggering the alarm. This paper exploits a next-generation risk-informed EEW DSS, which incorporates Multi-Criteria Decision-Making for evaluating the optimal decision. The proposed DSS integrates engineering-driven loss predictions associated with issuing/not issuing an EEW alert during an event, also considering possible system malfunctions. The DSS is demonstrated for the strategic Gioia Tauro seaport, located in the region of Italy with the highest seismic hazard. Real-time seismic risk analyses are conducted for various earthquake scenarios, accounting for event-parameter uncertainties that are integral to any EEW process and considering the multicomponent nature of the port as a system of interconnected elements. The results of these analyses are used as input to the proposed EEW DSS along with end-user risk preferences, to evaluate the optimal decision in each case and to define a series of risk-informed EEW warning thresholds for the port
