In this paper, we present the relationship between an oil spill-assessing approach, namely the event-decision network (EDN) and the formal safety assessment (FSA) of the International Maritime Organization (IMO). We focus on various points at which the Network incorporates basic features of the FSA in order to formulate a state-of-the-art, original strategic tool. In keeping with a safety–friendly effort, we developed the EDN, which implements a scenario-driven, generic tree framework. Moreover, the IMO, under the umbrella of decision-making, has introduced FSA, which is a systematic methodology for enhanced maritime safety by using risk and cost/benefit criteria. It is of interest to describe the introduced spill-scenario analysis/simulation and to pinpoint its interconnections with the aforementioned official instrument. Among other things, the goal of such a task is the enhancement of marine safety and the subsequent protection of seas from oil spills.