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Cause and effect charts

Q: Cause and effect charts used for system shutdowns, etc. is a concept/technique commonly used, but there seems to be no standardized methodology, and the format or the data produced varies as well. As you get deeper in the subject, you find that there is a wide variation in what is included and the definitions. We searched for "days" and visited with others in our industry looking for some source of documentation (book) or even an guideline by an organization such as ISA, etc., but at the end of the day, there was nothing. Do you have any reference book or source of information that may be of value? It is such an important "analysis," one would think there would be some form of consistency and "rules."

A: There is a short description of the technique in the first (1992) edition of the CCPS book Guidelines for Investigating Chemical Process Incidents, on pages 35-37, including some figures and standard symbols. The text attributes the technique to the Electric Power Research Institute (EPRI), and gives a specific reference:

Mosleh, A., et al, 1988, Procedures for Treating Common Cause Failures in Safety and Reliability Studies, EPRI NP-5613, Palo Alto, CA, Electric Power Research Institute.

I do not have this reference, so I can't comment on its value.

There is a 2nd edition of the CCPS book which I do not have, so their text may have changed from the first edition.

I have seen some text on this method in other books on incident investigation which are in the Rohm and Haas library, but I don't have specific references any more. They might try searching other books on investigation.

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