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SIS Failures Systematic Failures
Systematic Failures:
Produced by Human error.
•
Not easily detected and may only occur in specific
scenarios;
•
Can be created at any stage of the SIS lifecycle
•
Specification – Design – Manufacture – Installation –
Operation – Maintenance – Modification;
•
Very difficult to predict when and how they will occur;
•
Can only be removed by a modification to the SIS or
SIS procedures.