View methods side by side.
Choose up to four methods. Add them using the search and share the comparison by copying its link.
| Criterion |  Operations 5 Whys |  Engineering Fault Isolation |  Operations Barrier Analysis |  Operations Root Cause Analysis |
|---|---|---|---|---|
Purposedifferent | For a single, hard-to-explain deviation, the method exposes the causal chain behind the visible symptom. It keeps the cause open until a controllable condition emerges instead of a mere description. | In technical failures, the visible symptom often gets mixed up with the actual cause. Fault Isolation narrows the fault space and progressively reduces which part of the system is truly affected. | For a risk that can only be managed through multiple layers of protection, the method examines the effectiveness of each barrier. It shows where safeguards are missing, too weak, or fail under real conditions. | When a problem keeps recurring and the cause stays unclear, the method exposes the underlying mechanism. It separates symptom, guess, and robust explanation from one another. |
Complexitydifferent | Low | Medium | Medium | Medium |
Timedifferent | 15-30 min | 30-180 min | 2-4 h | 1-4 h |
Participantsdifferent | 2-6 | 1-6 | 2-6 | 3-8 |
Formatdifferent | Workshop | Workshop + async | Workshop + async | Workshop + async |
Outputdifferent | Root cause notes, Countermeasures | Fault Isolation Map, Test Log, Excluded Hypotheses, Narrowed Fault Area | Barrier Inventory, Failure Analysis per Barrier, Action Backlog | Problem Statement, Cause Hypotheses, Confirmed Causes, Action Plan |
Tagsno overlap | Root causeIncidentLeanProblem solving | TroubleshootingDiagnosisEngineering | Root causeSafetyIncident | Root causeProblem solvingQualityIncident |