Step 9 · Root-cause method
Root-cause analysis
Expert mode offers any of the RCA methods. Remember the separation the pack requires: the mechanism is what physically happened; the root cause is the correctable reason those conditions existed or were not controlled.
Cause-and-effect (Fishbone / Ishikawa)
5 Whys
Change / Difference Analysis
Events & Causal Factors (timeline)
Barrier Analysis
FMEA / FMECA
Fault Tree Analysis
Fault Tree Analysis
Model the logical combinations of basic events that cause a defined top event. Use AND/OR gates, decompose to basic events, and identify minimal cut sets.