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Through Normal Process Operation
‣
Revealing failures through normal process operations means that
‣
The
process behaviour
on its own
reveals
the failure of the subsystem, for
example
‣
The factory shuts down due to a safe failure in the pressure transmitter, or
‣
The vessel cannot be emptied due to a dangerous stuck close of the drain
valve
‣
This way of revealing failures is not useful
‣
Not from a safety point of view
‣
Not from a process availability point of view
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