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Prerequisites

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Step 1: Open the Initial Risk Ranking View

In the risksheet toolbar, switch to the Initial Risk Ranking view (view 3 of 9). This view reveals the severity, occurrence, detection, and pre-mitigation RPN columns while hiding unrelated fields.

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Step 2: Score Severity

Click the Severity cell for a failure mode and select a value from the 5-point aerospace scale aligned with ARP 4761:
ValueLabelMeaning
5CatastrophicLoss of function critical to safe flight; potential hull loss or multiple fatalities
4HazardousSignificant degradation of safety margins; substantially increased crew workload; potential serious injury
3MajorModerate degradation; crew can manage via normal procedures
2MinorMinimal crew impact; passenger discomfort possible
1No EffectNo impact on aircraft operation or safety
The cell renders with a color-coded label: red (5) → orange (4) → yellow (3) → yellow-green (2) → green (1).
In the SFMEA, severity values should align with the classification assigned in the upstream FHA. Mismatches between SFMEA severity and FHA failure condition classification will appear as discrepancies in certification audits. Cross-check against the FHA Classify Failure Effects guide.

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Step 3: Score Pre-Mitigation Occurrence

Click the Occurrence cell (pre-mitigation) and select the likelihood that this failure mode will occur during the product lifecycle — before any mitigation controls are applied. The field stores in premitigationFMOccurrence.

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Step 4: Score Pre-Mitigation Detection

Click the Detection cell (pre-mitigation) and select the ability to detect this failure mode before it reaches the customer — considering verification testing, inspection, and in-service monitoring. The field stores in premitigationDetection.
Occurrence and detection fields default to 0 (unscored). Any failure mode row with a 0 in any RPN component will show no calculated RPN — use the color coding as a quick audit to find unscored rows.

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Step 5: Verify the Auto-Calculated RPN

After scoring all three components, the Pre-Mitigation RPN column (premitigationRPN) populates automatically using the formula: 
RPN = Severity × Occurrence × Detection
The RPN cell displays both a numeric value and a color-coded risk tier label: diagram Row headers are also colored by the residual RPN tier, so high-risk rows stand out during review without needing to read individual cell values.

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Step 6: Score Post-Mitigation Occurrence and Detection

After adding mitigation actions (see Add Mitigation Actions), switch to the Final Risk Evaluation view (view 7) and update:
  • postmitigationFMOccurrence — residual likelihood after controls are applied
  • postmitigationDetection — residual detectability after controls
The postmitigationRPN field calculates automatically from these updated values.
The severity value represents the inherent consequence of the failure mode and must not be reduced to lower the RPN after mitigation. Only occurrence and detection scores change post-mitigation. Incorrectly reducing severity to achieve a low RPN will invalidate your safety case.
Once post-mitigation scores are entered, the Risk Control Effectiveness report computes RPN reduction as both a percentage and absolute value per component. Use this report during safety reviews to demonstrate that mitigations achieve the required risk reduction. See Read the FMEA Summary Report.

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Verification

You should now see:
  • All failure mode rows display numeric RPN values in both the Pre-Mitigation RPN and (after mitigation) Post-Mitigation RPN columns
  • Each RPN cell shows a color-coded label: red for HIGH, orange for MEDIUM, green for LOW
  • The Certification Readiness Scorecard shows RPN Scored % increasing toward 100% as scores are entered

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See Also

Code: .polarion/nextedy/models/rtm.yaml (0.54) · .polarion/pages/spaces/_default/Requirements Traceability Summary/page.xml, Verification Validation Summary/page.xml, Risk Control Effectiveness Report/page.xml, System Decomposition Report/page.xml, FMEA Coverage Report/page.xml, Classification Consistency Report/page.xml, System FMEA Report/page.xml, System Structure Navigator/page.xml (0.51) · datasets/sol-aero-ui-walkthrough/summary.md, navigation.md, dashboards/home-dashboard.md, dashboards/role-dashboards.md, dashboards/standards-compliance.md, risksheet-views/risksheet-views.md, work-item-types/data-model.md (0.50) · modules/RiskTemplates/SubSystem-FMEATemplate/attachments/risksheet.json (0.46) · .polarion/tracker/fields/failureMode-custom-fields.xml (0.46) · modules/RiskTemplates/DFMEATemplate/attachments/risksheet.json (0.46) · .polarion/tracker/fields/failureMode-failureModeSeverity-enum.xml (0.46) · .polarion/nextedy/sheet-configurations/MIL-STD-882E Hazard Tracking Log.yaml (0.45) · .polarion/tracker/fields/severity-enum.xml, status-enum.xml, priority-enum.xml, implementationStatus-enum.xml, riskSpecification-document-status-enum.xml (0.44) · .polarion/pages/scripts/velocity/nextedy_solutions.vm (0.43)