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Information Notice No. 93-69: Radiography Events at Operating Power Reactors
UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF NUCLEAR REACTOR REGULATION & OFFICE OF NUCLEAR MATERIAL SAFETY AND SAFEGUARDS WASHINGTON, D.C. 20555 September 2, 1993 NRC INFORMATION NOTICE 93-69: RADIOGRAPHY EVENTS AT OPERATING POWER REACTORS Addressees All holders of operating licenses or construction permits for nuclear power reactors and all radiography licensees. Purpose The U.S. Nuclear Regulatory Commission (NRC) is issuing this information notice to alert licensees to three events involving radiography at operating nuclear power plants. It is expected that recipients will review the information for applicability to their facilities and consider actions, as appropriate, to avoid similar problems. However, suggestions contained in this information notice are not NRC requirements; therefore, no specific action or written response is required. Description of Circumstances During three events in late 1992 and early 1993, employees at nuclear reactor facilities circumvented controls established to ensure the safe conduct of radiography. In each event, licensee personnel made unauthorized entries into areas where radiography was either just about to occur or in progress. No significant exposures resulted from these events; however, such events indicate a potential for significant exposures. Zion Event On December 9, 1992, an operator on routine rounds in the auxiliary building entered an area that was temporarily roped off and posted with a sign that read, "High Radiation Area; Radiography In Progress; Exclusion Area; Do Not Enter." The operator had read and signed a radiation work permit that allowed entry into high radiation areas normally encountered during operator rounds and felt that he was authorized to enter the area. However, Zion Station procedures require the use of a specific radiation work permit to enter areas in which radiography is taking place. Once inside the area, the operator encountered the radiographer who had just finished setting up his equipment and was doing a final boundary check. The radiographer noted he was not authorized to enter this area and escorted the operator from the radiography area. Subsequent interviews with the operator indicated that he was unaware of the significant radiological hazards associated with radiography. 9308260198. IN 93-69 September 2, 1993 Page 2 of 3 Kewaunee Event On March 27, 1993, a licensee supervisor made an unauthorized entry into an area in the turbine building that was temporarily roped off and posted with a sign that read "Radiation Area; Danger - Keep Out; Radiography In Progress; Contact Health Physicist Prior To Entry." The supervisor was obtaining temperature data in the area and had not read or signed the appropriate radiation work permit nor was he wearing proper dosimetry for the restricted area. After obtaining his data, he was observed leaving the area by Health Physics personnel who were responsible for watching the boundary while radiography was in progress. The Health Physics personnel were watching a different boundary when the licensee supervisor entered the unauthorized radiography area. Subsequent interviews with the individual indicated that he did not stop and read the sign. The licensee dose estimate indicated that the individual received an approximate dose of 0.001 mSv [0.1 mrem]. Dresden Event About 11:00 p.m. on February 13, 1993, two workers made an unauthorized entry into a posted radiologically controlled area established for radiography in the Unit 1 high-pressure coolant injection building. The two radiographers and the radiation protection technician involved with the radiography were on a meal break at the time of the entry. After the break, the radiographers and the radiation protection technician returned to the radiological controlled area, without verifying the area was free of personnel. Radiography was resumed and after 5 minutes of a 6 minute exposure had elapsed, the radiographers observed the two workers leaving the area. In its review of the event, the licensee determined that the two workers disregarded the postings and intentionally entered the area to hold a personal conversation in a room on the second floor of the building. Both workers were wearing thermoluminescent dosimeters but had not signed the appropriate radiation work permit for the radiography area. The route to the second floor led through the first-floor room where the radiography source was located, but was some distance away from the source. The licensee determined that doses of 0.15 mSv [15 mrem] and 0.30 mSv [30 mrem] were received by the two individuals. The two individuals received disciplinary action from the licensee. Discussion Radiography sources can create radiation fields in which permissible occupational dose standards can be exceeded in a short period of time. Although doses were low in the three events described above, each could have resulted in more serious exposures had the timing been different or had personnel been closer to the radiography source. Appropriate enforcement actions have been taken against the licensees as a result of the events. In . IN 93-69 September 2, 1993 Page 3 of 3 an effort to improve control during radiography, licensees have taken the corrective actions, including some of the following, as a result of their review of and lessons learned from the events. (1) Heightened employee awareness of the potential hazards associated with radiography through the use of station newsletters. (2) Enhanced general employee training to ensure that licensee employees receive information describing the radiological hazards associated with radiography and radiography controls. (3) Emphasized to licensee employees the importance with regard to safety of obeying radiological procedures, signs, and warnings. This information notice requires no specific action or written response. If you have any questions about the information in this notice, please contact the technical contacts listed below or the appropriate Office of Nuclear Reactor Regulation project manager. /s/'d by CJPaperiello /s/'d by BKGrimes Carl J. Paperiello, Director Brian K. Grimes, Director Division of Industrial Division of Operating Reactor Support and Medical Nuclear Safety Office of Nuclear Reactor Regulation Office of Nuclear Material Safety and Safeguards Technical contacts: William G. Snell, RIII (708) 790-5513 John B. Carrico, NMSS (301) 504-2634 Attachments: 1. List of Recently Issued NMSS Information Notices 2. List of Recently Issued NRC Information Notices .
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