RE: [Root_Cause_State_of_the_Practice] Boeing 747 loses Oxygen bottle: investigation without recommendations.
It depends on the circumstance as to what is most appropriate.
In the case of equipment failure, depending on significance (and time allotted by management) it can range from a relatively simple qualitative assessment of probability vs. consequence which any analyst can do (particularly when armed with a set of potential failure modes from your analysis and existing MTBF analysis data) to a more formal reliability prediction called upon from reliability engineers combined with evaluation of potential consequences of recurrence.
For other types of failures and to sell a particular set of corrective actions to management from a risk based and cost/benefit standpoint I typically use value engineering techniques, which are generally easily understood and relatively easy to perform.
What are you using for the “probability analysis”? I have been looking for something to help when discussing the effectiveness of corrective action discussions.
Tim Lovley, CSP, CFPS, CUSA
Director H&S Eastern Fleet
312E198e BB PIN
Learn from yesterday, don't repeat yesterday's mistakes today, and improve for tomorrow.
Good question. That is a common outcome whenever crucial evidence associated with an event is lost or destroyed. Usually an investigation bears fruit anyway. But in such cases I make it clear that conclusions are based on certain assumptions, accompanied by a probability analysis of the assumptions and the associated risks. If possible, practical corrective action(s) that address all the known possibilities are implemented. If not, mitigative actions are implemented that minimize consequences and capture/retain evidence should the event recur.
I’d be interested in hearing of additional actions investigators have taken.
It is hard to swallow (for investigators as well as principals), but we all know of investigations which -for some reason or another- have not resulted in a clear (set of) root cause(s) or effective remedial action(s). Here is an e! xample from the air transport industry.
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When was the last time you got trapped in this 'cul de sac'?
How did you handle the situation with (sr.) managers and principals?
Take care, Paul.