Systems Analysis using CAST and STPA methodologies - A Case Study on handling LPG

This study shows the effectiveness of Systems-Theoretic Accident Model and Processes (STAMP) concept and its dedicated methods Systems Theoretic Process Analysis (STPA) and Causal Analysis Based on System Theory (CAST) in analyzing accidents and designing a new process based on the learning from the accident analysis. To this end, CAST is used to analyze an accident case involving LPG and results are compared with open-source literature. The analysis begins with studying the organizational structure and then assessing the functional relationship between system components that lead to unsafe controls and hazard constraints. Suggestions for improvements to the safety control structure of their operations are given.