Abstract - nst10040003

DOE Order 5000.3A, "Occurrence Reporting and Processing of Operations Information," requires the

investigation and reporting of occurrences (including the performance of root cause analysis) and the

selection, implementation, and follow-up of corrective actions. The level of effort expended should be

based on the significance attached to the occurrence. Most off-normal occurrences need only a scaled-

down effort while most emergency occurrences should be investigated using one or more of the formal

analytical models. A discussion of methodologies, instructions, and worksheets in this document guides

the analysis of occurrences as specified by DOE Order 5000.3A.

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