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Proof Test Strategy
Hazardous Event Requiring Operation of the Safety Function
One technique is to utilise a demand on the safety function as a means to
identify dangerous failures.
The following criteria must be considered if this approach is to be taken:
•
Validation that the SIF prevented the hazardous event and not by other
means.
•
How failures in redundant channels will be detected.
•
How demand rate will be estimated.