Failure Modes and Effects Analysis (FMEA, FMECA)
A model for Safety analysis

Areas of Applicability: (comparison chart)
 Diagnostics / Prognostics  System Engineering  Maintainability
 Testability  Reliability  Life Cycle Cost
 Design-for-Test  Safety  Other

What - FMECAs are a spreadsheet-type approach to depicting the information about how failures manifest themselves in system-level effects. The addition of criticality turns the FMEA approach into a FMECA approach.

Why - FMECAs have been used extensively as a system-level abstraction to quantify the existence of safety critical behavior. FMECA's are a major contract item in reporting the failure capabilities of a system.

When - FMECA's are typically developed early through similarity analysis or as a conceptual view, and evolved later as a way of reporting on failure mode models. When performed early and with a functional approach, they are called FHA's or Functional Hazard Analysis. The FHA is used as a baseline into which all future identified failure modes must fit, and therefore fall within the original FHA scope.

Related Links - Failure Mode Dependency Models, Fault Trees, Reliability Block Diagrams