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Standard Enumerations

Design Assurance Levels (DAL A-E) — Criticality classifications assigned to failure conditions and functions based on the severity of their effects. DAL A is most critical; DAL E is least critical. Drives verification and documentation rigor. Failure Condition Classification — Categories for failure condition severity: Catastrophic, Hazardous, Major, Minor, and No Effect. Determines mitigation strategy and certification evidence requirements. Failure Mode Severity — FMEA severity ratings (1–10 scale) indicating the impact of a failure mode on system safety and function. Used in RPN (Risk Priority Number) calculations for SFMEA and DFMEA. Failure Mode Occurrence — Probability or frequency ratings (1–10 scale) for how often a failure mode is expected to occur. Combined with severity and detection for RPN scoring. Failure Mode Detection — Ratings (1–10 scale) for the likelihood that a failure mode will be detected before it reaches the customer or causes harm. Low detection scores indicate high-risk failure modes. Action Priority (AP) Levels — Priority classification for mitigation actions identified during FMEA and FTA. AP 1 (highest) through AP 4 (lowest) guide resource allocation and closure deadlines. Risk Control Type — Categories for control mechanisms: Design Control, Verification Control, Monitoring & Mitigation Control, and Administrative Control. Defines how hazards are managed across the development lifecycle. System Element Type Hierarchy — Taxonomy of system components: Hardware, Software, Firmware, Mechanical, Electrical, and Hydraulic. Enables allocation of failure modes and characteristics to design disciplines. Characteristic Type — Classifications for design characteristics tracked in DFMEA: Performance, Functional, Reliability, Safety, and Environmental. Links design features to failure modes and test cases. Security Assurance Level (SAL) — Security criticality levels (SAL 1–5) assigned to threats and security controls per DO-326A threat assessment. SAL 1 is least critical; SAL 5 is most critical.

Key Features

  • Standardized terminology across all analysis types (FHA, SFMEA, DFMEA, FTA, CCA, security)
  • Aerospace-certified scales aligned with DO-178C, DO-254, ARP 4754A, and MIL-STD-882E definitions
  • RPN calculation support for FMEA prioritization using severity, occurrence, and detection ratings
  • Traceability integration linking enumerations through requirements, characteristics, and test cases
  • Role-based filtering adapting enumeration views to safety engineer, design engineer, and certification workflows
  • Consistency validation enforcing enumeration constraints at document submission and certification checkpoints

Enumeration Reference Structure

EnumerationPurposeUsed InTypical Range
DALFunction and failure condition criticalityFHA, PSSA, SSAA (critical) to E (minimal)
Failure Condition ClassificationSeverity of consequencesFHA, PSSACatastrophic to No Effect
FM SeverityImpact magnitudeSFMEA, DFMEA, RPN1 (no impact) to 10 (catastrophic)
FM OccurrenceLikelihood of failureSFMEA, DFMEA, RPN1 (remote) to 10 (frequent)
FM DetectionProbability of catching failureSFMEA, DFMEA, RPN1 (certain) to 10 (impossible)
Action PriorityMitigation urgencySFMEA, DFMEA, risk trackingAP 1 (urgent) to AP 4 (defer)
Risk Control TypeMitigation mechanismSafety assessment, design reviewsDesign, Verification, Monitoring, Admin
System Element TypeComponent categorySystem architecture, DFMEAHardware, Software, Firmware, Mechanical, etc.
Characteristic TypeDesign property classDFMEA, environmental qualificationPerformance, Functional, Safety, Environmental
Security SALThreat criticalitySecurity assessment, DO-326ASAL 1 (low) to SAL 5 (critical)

How Enumerations Drive Analysis

diagram Start with Design Assurance Levels (DAL A-E) to understand criticality assignment, then explore FMEA severity and occurrence scales for risk prioritization. Security projects should review Security Assurance Level (SAL) for threat classification.
Code: .polarion/tracker/fields/systemElementType-enum.xml, systemElement-status-enum.xml (0.47) · .polarion/tracker/fields/designRequirement-subType-enum.xml, environmentalCategory-enum.xml, fta-gateType-enum.xml, cca-analysisType-enum.xml, controlType-enum.xml, riskControlType-enum.xml, verificationMethod-enum.xml, testLevel-enum.xml (0.45) · .polarion/tracker/fields/complianceObjective-standard-enum.xml, complianceObjective-status-enum.xml, complianceRequirement-complianceStatus-enum.xml, complianceRequirement-evidenceType-enum.xml (0.44) · .polarion/tracker/fields/resolution-enum.xml, .polarion/tracker/fields/changerequest-resolution-enum.xml, .polarion/tracker/fields/changerequest-status-enum.xml, .polarion/tracker/fields/work-record-type-enum.xml, .polarion/tracker/fields/yesno-enum.xml (0.43) · .polarion/tracker/fields/severity-enum.xml, status-enum.xml, priority-enum.xml, implementationStatus-enum.xml, riskSpecification-document-status-enum.xml (0.42) · .polarion/tracker/fields/mappings.xml (0.40) · .polarion/tracker/fields/hazard-hazardCategory-enum.xml, hazard-operationalPhase-enum.xml, hazard-acceptanceAuthority-enum.xml (0.37) · .polarion/tracker/fields/testCase-custom-fields.xml, desReq-custom-fields.xml, processStep-custom-fields.xml, characteristic-custom-fields.xml, systemElement-custom-fields.xml, commonCauseEvent-custom-fields.xml, riskControl-custom-fields.xml, task-custom-fields.xml, custom-fields.xml (0.37) · .polarion/pages/scripts/velocity/nextedy_solutions.vm (0.36) · .polarion/tracker/fields/complianceObjective-custom-fields.xml (0.36)