Principal Investigator Nancy Leveson
Co-investigator Wesley Harris
At the foundation of the current limitations in engineering for safety and mission assurance is the almost exclusive use of a model of accidents that assumes they arise from a chain of failure events and human errors. While satisfactory for the relatively simple electromechanical and industrial systems for which the model was developed, it does not explain system accidents (arising from interactions among system components rather than individual component failures) and is inadequate for today's complex, software-intensive, human-machine systems. We are developing accident models based on systems theory that can serve as the foundation for new and improved approaches to accident investigation and analysis, hazard analysis and accident (loss) prevention, risk assessment and risk management, and performance monitoring. Such models need to include organizational and management factors and well as technical if they are to prevent losses in complex systems.