[en] Section 208 of the Energy Reorganization Act of 1974 identifies an abnormal occurrence as an unscheduled incident or event that the Nuclear Regulatory Commission determines to be significant from the standpoint of public health and safety and requires a quarterly report of such events to be made to Congress. This report covers the period April through June 1993, and discusses four abnormal occurrences at NRC-licensed facilities, three involving medical brachytherapy misadministrations and one involving a research reactor that operated without a safety system. One pool irradiation facility contamination event, two medical misadministrations (one ''sodium iodide'' and one brachytherapy), and one industrial radiographer overexposure event that were reported by NRC Agreement States are also discussed. The report also contains information updating one previously reported abnormal occurrence and information on three other events of interest