手法を比較

	感度分析と故障の木解析（FTA-SA）	イベントツリー解析 (ETA)
分野	実験計画法	信頼性
系統	Process / pipeline	Process / pipeline
提唱年	1961 (FTA); sensitivity integration formalised 1970s–1980s	2002
提唱者	H. A. Watson (Bell Labs, FTA, 1961); integrated sensitivity extensions developed through nuclear safety research (Vesely et al., 1981)	Andrews & Moss
種類	Quantitative reliability and risk analysis technique	Forward inductive logic tree
原典	Vesely, W. E., Goldberg, F. F., Roberts, N. H., & Haasl, D. F. (1981). Fault Tree Handbook. US Nuclear Regulatory Commission, NUREG-0492.	Andrews, J. D., & Moss, T. R. (2002). Reliability and Risk Assessment (2nd ed.). Professional Engineering Publishing. ISBN: 978-1-86058-290-5
別名	FTA-SA, fault tree sensitivity analysis, FTA with importance measures, probabilistic sensitivity analysis in fault trees	ETA, Event Sequence Diagram Analysis, Initiating Event Analysis, Olay Ağacı Analizi
関連	3	2
概要	Sensitivity analysis integrated with fault tree analysis (FTA-SA) is a quantitative reliability engineering method that first models how system failure can occur through a hierarchical Boolean logic tree, then systematically varies the probability of each basic event to determine which components drive overall system failure risk most strongly. Widely used in nuclear, aerospace, chemical, and safety-critical system design, it prioritises mitigation effort and reveals which uncertainty in input data matters most.	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.