A Model Based Framework for Safety Risk Assessment using Systems Theoretic Process Analysis for ASIL Justification According to ISO 26262

With advancements in automotive systems, particularly in autonomous and electric vehicles, the increasing complexity of modern vehicular systems is challenging the traditional safety analysis methods prescribed by ISO 26262. Failure-based safety analysis techniques often struggle to identify systematic risks arising from software interactions, human factors, and emergent behaviors. This paper addresses this gap by providing a framework that utilizes Systems-Theoretic Process Analysis (STPA) to complement ISO 26262’s hazard analysis methods by considering emergent hazards during the justification of Automotive Safety Integrity Levels (ASIL). The aim of this paper is to present a model-driven hybrid methodology that combines traditional fault-based approaches with STPA for traceable ASIL justification, thereby enhancing ISO 26262’s Hazard Analysis and Risk Assessment (HARA) process. This approach allows for the integration of contemporary safety analysis techniques like STPA into existing safety workflows without displacing the core principles of the ISO 26262 standard.