Copyright © Risknowlogy®. All rights reserved. v9
Other points to consider
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Are you sure the non-SIS installed IPL’s are providing the risk reduction you need?
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Are the assumptions you made in the HAZOP / LOPA still true? (?Check
assumptions at proof test time?)
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Issues I haven’t thought through yet
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Redundancy in the “black box”
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Statistical confidence of historic data (same as prior use?)
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