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NUREG 0933

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TASK I.A.1: OPERATING PERSONNEL AND STAFFING Complex transients in nuclear power plants place high demands on the operators in the control room. The objective of the actions described in this task was to increase the capability of the shift crews in the …
The objectives of this task were to: (1) improve the capability of operators and supervisors to understand and control complex reactor transients and accidents; (2) improve the general capability of an operations organization to respond rapidly and …
The objectives of this task were to: (1) upgrade the requirements and procedures for nuclear power plants operator and supervisor licensing to assure that safe and competent operators and senior operators are I charge of the day-to-day operation of …
The objectives of this task were to: (1) establish and sustain a high level of realism in the training and retraining of operators, including dealing with complex transients involving multiple permutations and combinations of failures and errors; and (2) …
The objectives of this task were to: (1)   Improve licensee safety performance and ability to respond to accidents by upgrading the licensee groups responsible for radiation protection and plant operation in such areas as staff size; education and …
The objective of this task was to improve the quality of procedures to provide greater assurance that operator and staff actions were technically correct, explicit, and easily understood for normal, transient, and accident conditions. The overall content, …
The objective of this task was to improve the ability of nuclear power plant control room operators to prevent accidents or cope with accidents if they occur by improving the information provided to them. ITEM I.D.1: CONTROL ROOM DESIGN REVIEWS This item …
The objectives of this task were to: (1) increase the capability of shift crews to operate facilities in a safe and competent manner by assuring that training for plant changes and off-normal events was conducted; and (2) review the comprehensiveness of …
The objective of this task was to demonstrate by testing and analysis that the relief and safety valves, block valves, and associated piping in the reactor coolant system (RCS) were qualified for the full range of operating and accident conditions; …
The objective of this task was to improve the reliability and capability of nuclear power plant systems for removing decay heat and achieving safe shutdown conditions following transients and under post-accident conditions. ITEM II.E.3.1: RELIABILITY OF …
The objective of this task was to evaluate whether existing requirements for valve testing provided adequate assurance of performance under design conditions. ITEM II.E.6.1: TEST ADEQUACY STUDY DESCRIPTION Historical Background The purpose of this TMI …
The objective of this task was to increase the reliability and diversification of the electrical power supplies for certain safety-related equipment. ITEM II.G.1: POWER SUPPLIES FOR PRESSURIZER RELIEF VALVES, BLOCK VALVES, AND LEVEL INDICATORS DESCRIPTION …
The objectives of this task were to perform systems reliability analyses and to effect changes in emergency operating procedures and operator training to improve the capability of plants to mitigate the consequences of the small-break LOCAs and …
The objectives of this task are: (1) to improve and expand the NRC training program for the technical staff and resident inspectors, including, where appropriate, hands-on training; and (2) to establish a program to provide technically qualified …
DESCRIPTION The issue was raised after the occurrence of various incidents of water hammer that involved steam generator feedrings and piping, emergency core cooling systems, RHR systems, containment spray, service water, feedwater, and steam lines. The …
DESCRIPTION Historical Background This issue deals with a concern for the availability of adequate recirculation cooling water following a LOCA when long-term recirculation of cooling water from the PWR containment sump, or the BWR RHR system suction …
DESCRIPTION Historical Background This NUREG-0471 [1] item concerned staff positions [2] BTP EISCB 18 and BTP RSB 6-11 which required physical locking out of electrical sources to specific MOVs in the ECCS. The existing staff positions established the …
DESCRIPTION Historical Background This NUREG-0471 [1] item involved the development of a time criterion for safety-related operator actions (SROA), including a determination of whether or not automatic actuation was to be required. At the time this issue …
DESCRIPTION A number of applicants for operating licenses have been performing sump tests to demonstrate ECCS operability during the recirculation phase following a postulated loss-of-coolant accident. These tests have shown that vortex formation is not …
DESCRIPTION The BWR pressure relief system is designed to prevent overpressurization of the reactor coolant pressure boundary (RCPB) under the most severe abnormal operational transient: closure of the main steam line isolation valves (MSIVs) with failure …
DESCRIPTION Historical Background This NUREG-0471 [1] item, as presently formulated, involves the conduct of analytical and experimental work to determine whether or not destructive overspeeds could be attained and to determine if corrective actions are …
DESCRIPTION Offsite power system frequency decay, depending on the rate of decay, could provide an electrical brake on the reactor coolant pump motors that could slow the pumps faster than the assumed flywheel coastdown flow rates normally used in …
DESCRIPTION Historical Background The operating experience of nuclear power plants indicates that a number of valves, valve operators, and pumps fail to operate as specified in the technical specifications either under testing conditions or when they are …
DESCRIPTION Background Flow-induced vibrations caused by vortex shedding resulting from rapid area change, buffeting due to random flow turbulence, fluid structures interaction instability, leakage excitation, steady operation of positive displacement …
DESCRIPTION Historical Background This concern was identified by the ACRS as a result of their review [1] of LERs covering a period from 1976 through 1978 and, subsequently, a comprehensive review of the problem was completed which covered the LERs and …

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