Learning About Ambiguity.

This paper proposes a classification system for definition, analysis and management of the primary ambiguities influencing the performance of engineered systems. One category of ambiguities (Intrinsic) is addressed with 'hardware and structure' approach that is intended to develop and maintain 'robust' damage and defect-tolerant systems. The other category of ambiguities (Extrinsic) is addressed with 'human and organizational' approach intended to develop and maintain high reliability organizations having high reliability management with high reliability systems. Proactive (performed before activities are conducted), Reactive (performed after activities are conducted) and Interactive (performed while activities are conducted) risk management approaches and strategies are described to help develop and maintain systems having desirable performance characteristics, including acceptable 'safety'. Results from a study of seven organizations that worked for more than 10 years to implement these approaches and strategies to assess and manage ambiguities are summarized. [ABSTRACT FROM AUTHOR]