Safety Integrity Level vs Lifecycle Cost
Use rigorous LOPA and hazard analysis to assign only the SIL level genuinely required, avoiding costly over-engineering.
CyberTRIZ analysis · Seveso contradiction FS007 · one of 8,235 worked contradictions published by CyberTRIZ.AI
Regulations
Business Context
Higher Safety Integrity Levels (SIL) reduce the probability of dangerous
failures and improve risk reduction. Achieving higher SIL targets,
however, requires additional redundancy, testing, documentation, and
engineering effort throughout the system lifecycle.
The Contradiction
Higher SIL improves risk reduction.
Higher SIL increases lifecycle cost.
Why It Exists
Increasing SIL requirements affects equipment selection, system
architecture, proof testing, validation, maintenance, and engineering
documentation.
Direction
Determine SIL requirements through rigorous hazard analysis and LOPA
rather than applying unnecessarily conservative integrity levels.