Step 1: Planning and Preparation
Purpose: Define the FMEA scope, boundaries, and project plan.
Key Activities:
- Determine the purpose and scope of the FMEA project
- Define analysis boundaries (what is included and excluded)
- Assemble cross-functional FMEA team
- Develop project plan and timeline
- Collect necessary input information
- Determine tools and templates to be used
Key Outputs:
- FMEA project plan
- 5T document (Intent, Timing, Team, Tasks, Tools)
Step 2: Structure Analysis
Purpose: Identify and decompose the structural hierarchy of the analysis subject.
Key Activities:
- Build product/process structure tree
- Define system, subsystem, and component hierarchies
- Identify interfaces and interactions
- Clarify focus element and its upper/lower levels
Tools:
Structure tree, block diagram, boundary diagram, process flow diagram
Step 3: Function Analysis
Purpose: Associate each element in the structure with its functions and requirements.
Key Activities:
- Define functions for each structural level
- Specify quantifiable performance requirements
- Establish relationships between functions
- Identify regulatory and safety-related functions
Tools:
Function tree, function network, P-diagram (Parameter diagram), interface matrix
Step 4: Failure Analysis
Purpose: Identify potential failure modes, effects, and causes.
Key Activities:
- Based on function analysis, determine possible failure modes for each function
- Analyze failure effects (consequences to higher system/end user)
- Identify root causes of failure (lower-level element failures)
- Build complete failure chains (Cause > Mode > Effect)
Tools:
Failure network diagram, fishbone diagram (Ishikawa), Fault Tree Analysis (FTA)
Step 5: Risk Analysis
Purpose: Evaluate existing controls and determine risk levels.
Key Activities:
- Identify existing prevention controls
- Identify existing detection controls
- Rate Severity (S), Occurrence (O), and Detection (D)
- Determine Action Priority (AP) — H/M/L
Key Change (vs. 4th Edition):
The new handbook uses Action Priority (AP) to replace traditional RPN ranking. AP is determined as High/Medium/Low based on S-O-D combination lookup tables, avoiding the limitations of simple RPN multiplication ranking.
Step 6: Optimization
Purpose: Develop and implement improvement actions to reduce risk.
Key Activities:
- Develop improvement actions for AP = High items (mandatory)
- Develop improvement actions for AP = Medium items (recommended)
- Assign responsible persons and target completion dates
- Implement improvement actions
- Re-evaluate S/O/D and AP after implementation
- Verify improvement effectiveness
Optimization Strategy Priority:
- Eliminate the failure cause (design change)
- Reduce occurrence frequency (strengthen prevention controls)
- Improve detection capability (strengthen detection controls)
Step 7: Results Documentation
Purpose: Record FMEA results and create traceable quality documentation.
Key Activities:
- Complete all fields in the FMEA form
- Write FMEA summary report
- Transfer results to Control Plan and Work Instructions
- Report key risks and improvement status to management
- Archive as part of organizational knowledge base
- Establish periodic review and update cycle (living document)