手法を比較

	リスクベース故障木解析	故障モード影響解析 (FMEA)
分野	実験計画法	実験計画法
系統	Process / pipeline	Process / pipeline
提唱年	1961 (FTA origin); risk-based integration formalised 1975–1981	1949 (military); widespread industrial adoption 1970s–1980s
提唱者	H.A. Watson (Bell Labs) and developed further by Boeing/U.S. Air Force; risk-based extension via NRC probabilistic risk assessment programs	U.S. Military / NASA (formalized by MIL-P-1629, 1949)
種類	Quantitative safety and reliability analysis	Proactive risk analysis technique
原典	Vesely, W. E., Goldberg, F. F., Roberts, N. H., & Haasl, D. F. (1981). Fault Tree Handbook. U.S. Nuclear Regulatory Commission, NUREG-0492.	Stamatis, D. H. (2003). Failure Mode and Effect Analysis: FMEA from Theory to Execution (2nd ed.). ASQ Quality Press. ISBN: 978-0873895989
別名	RB-FTA, risk-informed FTA, quantitative fault tree analysis, probabilistic fault tree analysis	FMEA, Failure Modes and Effects Analysis, FMECA, Failure Mode Effects and Criticality Analysis
関連	6	6
概要	Risk-based fault tree analysis (RB-FTA) combines classical fault tree analysis with explicit quantitative risk assessment. Starting from an undesired top event, the analyst decomposes it into contributing causes using AND/OR logic gates, assigns failure probabilities to basic events from reliability databases or historical data, and then propagates those probabilities through the tree to compute top-event likelihood. The result is expressed as risk — probability weighted by consequence severity — enabling prioritisation of safety interventions by their actual risk reduction impact.	Failure Mode and Effects Analysis (FMEA) is a structured, proactive risk management technique used to identify potential failure modes in a system, process, or product design, evaluate their consequences, and prioritize corrective actions before failures occur. Originally developed for the U.S. military in 1949 and later adopted by NASA, automotive, and manufacturing industries, FMEA is now a cornerstone quality-engineering tool embedded in standards such as AIAG-VDA and ISO 9001-aligned processes.