Report to Congress on Abnormal Occurrences – Fiscal Year 2019 (NUREG-0090, Volume 42)

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Publication Information

Manuscript Completed: June 2020
Date Published: June 2020

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, as amended (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) changed the AO reporting frequency from quarterly to annually.

This report describes nine events in Agreement States and no events involving NRC licensees that were identified as AOs during fiscal year (FY) 2019. These events are based on the criteria defined in the NRC Policy Statement on "Abnormal Occurrence Reports," issued on October 2, 2017 (82 FR 45907). Seven AOs were medical events as defined in Title 10 of the Code of Federal Regulations (10 CFR) Part 35, "Medical Use of Byproduct Material." The eighth AO was a human exposure event and the ninth AO involved the theft and recovery of Category 2 sources, as defined in 10 CFR Part 37, "Physical Protection of Category 1 and Category 2 Quantities of Radioactive Material." The NRC did not identify any events at commercial nuclear power plants as AOs.

Agreement States are those States that have entered into formal agreements with the NRC, in accordance with Section 274 of the Atomic Energy Act of 1954, as amended (AEA) (Public Law 83–703), to regulate certain quantities of AEA material at facilities within the States' borders. Currently, there are 39 Agreement States.

Appendix A, "Abnormal Occurrence Criteria," to this report presents the NRC's criteria for identifying AOs. The NRC identified one event during FY 2019 that meets the guidelines for inclusion in Appendix B, "Other Events of Interest." The event received significant media coverage due to extensive contamination of personnel and building structures due to the breaching of a sealed cesium-137 source. No events meet the guidelines for inclusion in Appendix C, "Updates of Previously Reported Abnormal Occurrences." Appendix D, "Glossary," defines terms used throughout this report. Appendix E, "Conversion Table," presents conversions commonly used when calculating doses.

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