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Hybrid applications of IEC61511 – Laurie Blackmore
Assessment methods:
(2) Use 61511 OOM approach (not really cost/benefit for reasons above)
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Need to define tolerable $ risk per year as starting point for graph calibration or
LOPA TMEL
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Implementing an asset SIF costs money (CAPEX and OPEX) so tolerable risk must
be > that cost, say x 10 to result in an IL1 function
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BUT implementation cost is variable (as above) so maybe take a generic figure?
Most asset assessments result in more protection than is justified
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Asset Assessment Issues