(74c) Analysis of Shell Moerdijk Accident by Systems-Theoretic Accident Model and Processes and Bowtie Analysis

As a Systems-Theoretic Accident Model and Processes (STAMP) was used to analyze the Shell Moerdijk Accident by MIT¡¯s Nancy Leveson Professor as a bench-mark case. This research intended to use the Systems-Theoretic Process Analysis (STPA) to identify the hazards, safety requirements and constrains, unsafe control actions in the operational control structure in order to understand the flaws and context in decision making process. The results were also compared with the causes-incident-consequences-barriers by the Bowtie Analysis (BTA) to compare both methods and to demonstrate their usefulness. It could be summarized that STPA yielded many possible cases with components of different types and degrees of hazards while BTA limited by their possible cause-consequence links. While comparing to Casual Analysis based on STAMP (CAST), BTA displayed a simple but limited analysis without the possible extensions into the complex social-management-technological relationships.