手法を比較

	Bow-Tie Risk Analysis	イベントツリー解析 (ETA)
分野	Disaster Studies	信頼性
系統	Process / pipeline	Process / pipeline
提唱年	2016	2002
提唱者	Synthesized review by de Ruijter & Guldenmund; standardized in ISO/IEC 31010	Andrews & Moss
種類	Barrier-centred cause-consequence risk diagram and analysis	Forward inductive logic tree
原典	de Ruijter, A., & Guldenmund, F. (2016). The bowtie method: A review. Safety Science, 88, 211-218.	Andrews, J. D., & Moss, T. R. (2002). Reliability and Risk Assessment (2nd ed.). Professional Engineering Publishing. ISBN: 978-1-86058-290-5
別名	Bowtie Method, Bow-Tie Diagram, Barrier Analysis (Bow-Tie), Cause-Consequence Barrier Model	ETA, Event Sequence Diagram Analysis, Initiating Event Analysis, Olay Ağacı Analizi
関連	3	2
概要	Bow-tie risk analysis is a barrier-centred technique that places a single top event — the moment control over a hazard is lost — at the knot of a diagram, branches its possible causes to the left and its possible consequences to the right, and arrays along each pathway the barriers meant to prevent or mitigate it. The shape gives the method its name: the fanning threats and consequences form the two halves of a bow tie around the central event. de Ruijter and Guldenmund's 2016 review in Safety Science documents how the approach grew popular precisely because it combines, in one readable picture, the cause logic of a fault tree and the consequence logic of an event tree while foregrounding the controls that managers actually own. ISO/IEC 31010 lists bow-tie analysis among standard risk-assessment techniques, used both qualitatively to communicate risk and barrier coverage and quantitatively to estimate consequence likelihoods.	Event Tree Analysis (ETA) is a forward inductive technique used in reliability and risk engineering to model the possible outcomes that follow an initiating event. Starting from a single undesired event, ETA traces all subsequent event sequences through a binary branching tree representing the success or failure of safety barriers and protective systems. Introduced formally in reliability and risk literature by Andrews and Moss (2002), it is widely applied in nuclear, chemical, and aerospace industries to quantify accident sequence probabilities and guide safety decision-making.