Select level of analysis Several levels of analysis are possible Basic- Only the hazard, top event, threats, and consequences are identified Standard without degradation factors- Adds barriers to basic bow tie diagrams Standard with degradation factors and controls- Adds degradation factors and controls to the standard bow tie diagram Enhanced- Details are documented for barriers and controls Multilevel- Shows controls supporting controls. The level of analysis used is determined by the purpose of the study. For example, if the purpose is communication of hazards, basic bow ties maybe sufficient whereas if the purpose is barrier management, enhanced bow ties will be needed.
