Abubakr Gameil's recent question, "Can we truly quantify the 'unquantifiable' risks of aging strategic infrastructure before the first crack appears? Or are we merely reacting to shadows of the past," brought to mind the influence of common cause failures in high-reliability systems.
A NASA paper, Common Cause Failures and Ultra Reliability by Harry W. Jones can be found https://share.google/t4KsduS3kp0iyw8RO
My experience with common cause failures came from a PRA I led to quantify the blowout risk of an ultra-high-reliability well. The results, principally an annual probability of failure, were extremely low, but efforts to reduce to further reduce the risk were impossible. The culprits were common cause failures built into the model.
Have others had experience here, and what can you share? Returning to Abubakr Gameil's question, the existence of common cause failures means there is a limit to how safe we can make our systems. Maybe I'm wrong here, and someone can point out the error in my thinking.
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Mitch Winkler P.E.(inactive), M.ASCE
Houston, TX
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