Incorporating New Methods of Classifying Domain Information for Use in Safety Hazard Analysis

The increase of interacting humans and autonomous components in complex systems necessitates rigorous methods to classify domain information pertaining to controllers in the system. SystemsTheoretic Process Analysis (STPA) was developed at MIT as a method for identifying hazardous scenarios from a system design in order to generate functional system requirements to eliminate or control those scenarios. An STPA analysis, while systems-based and including human operators (e.g., pilots and air-traffic controllers) in the scenarios, is currently limited in the types of human contribution to accidents that it can identify (which are primarily related to situation awareness). This paper extends STPA in three ways: first, the analysis of the controller mental model was updated to include more system features; second, fundamental human-engineering considerations were added; and third, types and sources of decision-making influences that transfer from the planning cycle to the operations cycle were identified.