System Safety Assessment
SSASection 06: System Safety & Functional Safety
Definition
A systematic, comprehensive evaluation of the implemented system design to show that the safety objectives established in the FHA are met by the final design. The SSA compiles and evaluates all safety analysis results — including quantitative analyses (fault trees, reliability analyses), qualitative assessments, common cause analyses, and verification evidence — to provide a complete safety argument for the system. The SSA demonstrates that each failure condition identified in the FHA has been addressed and that the applicable probability and qualitative requirements are satisfied.
Where This Shows Up
The SSA is the culmination of the safety assessment process. It is the comprehensive safety argument presented to the certification authority demonstrating that the system, as designed and implemented, meets all safety requirements. The SSA references evidence from testing, analysis, fault trees, FMEA results, common cause analysis, and zonal safety analysis. It is a living document during certification and forms a key part of the certification evidence package.
Primary Sources
Defines the SSA process and its role as the final safety assessment integrating all evidence.
Describes the certification authority's expectations for the SSA as compliance evidence.
Artifacts Produced
Comprehensive document compiling all safety evidence, analyses, and arguments demonstrating compliance with safety objectives for the system.
Related Terms
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