Report to Congress on Abnormal Occurrences – Fiscal Year 2011 (NUREG-0090, Volume 34)

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Publication Information

Manuscript Completed: May 2012
Date Published: May 2012

Office of Nuclear Regulatory Research
United States Nuclear Regulatory Commission
Washington, DC 20555-0001

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Section 208 of the Energy Reorganization Act of 1974 (Public Law 93-438) defines an "abnormal occurrence" (AO) as an unscheduled incident or event that the U.S. Nuclear Regulatory Commission (NRC) determines to be significant from the standpoint of public health or safety. The Federal Reports Elimination and Sunset Act of 1995 (Public Law 104-66) requires that the NRC report AOs to Congress annually.

This report describes five events that the NRC identified as AOs during fiscal year (FY) 2011 based on the criteria defined in this report's Appendix A, "Abnormal Occurrence Criteria and Guidelines for Other Events of Interest." The first event at an NRC-licensed facility involved radiation exposure to an embryo/fetus, and the second was an event of high safety significance at a commercial nuclear power plant. The other three events occurred at NRC-regulated medical institutions and are medical events, as defined in Title 10 of the Code of Federal Regulations (10 CFR) Part 35, "Medical Use of Byproduct Material."

In addition, this report describes 19 events that Agreement States identified as AOs during FY 2011, based on the criteria in Appendix A to this report. Agreement States are those States that have entered into formal agreements with the NRC, pursuant to Section 274 of the Atomic Energy Act (AEA), to regulate certain quantities of AEA material at facilities located within their borders. Currently, there are 37 Agreement States. The first Agreement State event involved radiation exposure to an embryo/fetus, the second event involved an exposure to the extremities of a radiographer, and the third event involved a stolen radiography camera. The other 16 Agreement State events were medical events, as defined in 10 CFR Part 35.

Appendix A to this report presents the NRC's criteria for selecting AOs, as well as the guidelines for selecting "other events of interest." Appendix B, "Updates of Previously Reported Abnormal Occurrences," provides updated information for one event reported in the FY 2010 "Report to Congress on Abnormal Occurrences" regarding the medical event at Providence Hospital in Novi, Michigan. During FY 2011, three items were identified as meeting the guidelines for inclusion in Appendix C, "Other Events of Interest." These three events occurred at nuclear power plants. Appendix D, "Glossary," presents definitions of terms used throughout this report. Appendix E, "Conversion Table," presents conversions commonly used when calculating doses.

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