Comparer des méthodes

	Bow-Tie Risk Analysis	Preliminary Hazard Analysis
Domaine	Disaster Studies	Disaster Studies
Famille	Process / pipeline	Process / pipeline
Année d'origine	2016	2008
Auteur d'origine	Synthesized review by de Ruijter & Guldenmund; standardized in ISO/IEC 31010	Military system-safety practice (MIL-STD-882); codified in CCPS guidelines
Type	Barrier-centred cause-consequence risk diagram and analysis	Early-stage qualitative hazard identification and ranking
Source fondatrice	de Ruijter, A., & Guldenmund, F. (2016). The bowtie method: A review. Safety Science, 88, 211-218.	Center for Chemical Process Safety (CCPS). (2008). Guidelines for Hazard Evaluation Procedures (3rd ed.). Wiley-AIChE, Hoboken, NJ. ISBN: 9780471978152
Alias	Bowtie Method, Bow-Tie Diagram, Barrier Analysis (Bow-Tie), Cause-Consequence Barrier Model	PHA, Preliminary Hazard List Analysis, Early Hazard Analysis, Conceptual Hazard Analysis
Apparentées	3	3
Résumé	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.	Preliminary hazard analysis, or PHA, is an early-stage, qualitative technique for identifying the hazards inherent in a system before its design is detailed enough for more rigorous methods, and for ranking those hazards so that the riskiest receive attention first. Conducted in the concept or preliminary design phase, it works from the system's energy sources, hazardous materials, intended functions and operating environment to compile a hazard list, postulate how each hazard could lead to harm, and assign each a risk level from severity and likelihood ratings. The CCPS Guidelines for Hazard Evaluation Procedures present it as a foundational hazard-evaluation method, and ISO/IEC 31010 includes it among standard risk-assessment techniques. Because it is applied when changing the design is still cheap, the PHA's chief value is steering early design decisions and identifying which hazards warrant deeper study by methods such as HAZOP, FMEA or quantitative risk assessment.