stpa-overview

STPA hazard analysis follows a four-step workflow: define losses and hazards, model the control structure, identify unsafe control actions, and derive causal loss scenarios with actionable mitigations. This systematic process ensures thorough safety assessment for complex control systems.

STPA is a System Theoretic Process Analysis method for identifying hazards in complex control systems. You need STPA for safety engineering when analyzing software-intensive, physical, or AI-driven systems where control-feedback loops and operational constraints must be modeled and assessed.

You identify unsafe control actions by modeling the system's control-feedback structure and evaluating where commands could cause hazards. For AI-driven systems, STPA maps operational constraints and assesses how control actions could lead to unsafe scenarios and losses.

Yes, STPA works for physical systems and software-intensive control loops. The method applies cross-domain by modeling control-feedback loops and operational constraints to identify hazards and unsafe control actions in software-intensive, physical, and AI-driven systems.

The best way to document loss scenarios and safety constraints is through a structured STPA workflow that records findings in project files. This involves iteratively documenting losses, hazards, constraints, unsafe control actions, and causal loss scenarios with actionable mitigations.