NUREG 0933
Displaying 51 - 68 of 68
DESCRIPTION Historical Background This issue was raised [1] in March 1985 to address the staff's concern that there were no requirements for dynamic qualification testing or dynamic surveillance testing of large bore hydraulic snubbers (> 50 kips load …
1
DESCRIPTION Historical Background This issue was identified in a RRAB memorandum [1] in March 1985 and addressed the possibility of relay contact chatter during a seismic event and its resulting effect upon safety and safety-related electrical control …
1
DESCRIPTION Historical Background On January 27, 1985, a dented and leaking tendon grease cap was found during inspections at Farley Unit 2 prior to the integrated leak rate test of the prestressed concrete containment structure. Subsequent detailed …
1
DESCRIPTION In December 1984, the staff recommended in SECY-83-357B [1] that rulemaking with regard to H 2 control for LWRs with large, dry containments could be safely deferred due to the greater inherent capability of these containments to accommodate …
1
DESCRIPTION Historical Background The issue of deinerting upon discovery of RCS leakage was identified [1] by DL/NRR, based on data collected by OIE. The related but separate concern of deinerting with one train of a safety system inoperable was also …
1
DESCRIPTION The issue, as originally proposed, [1] addressed the concern for fission product removal by the containment sprays and suppression pools in PWRs and BWRs, respectively; however, it was expanded to include PWR plants that use ice condenser …
1
DESCRIPTION Historical Background This issue was identified [1] by NRR when concerns were expressed that the seismic loading on equipment and pipe-mounted components may have been underestimated. These concerns could be divided into two sub- issues: …
1
DESCRIPTION Historical Background This issue was identified [1] by DSIR/RES and addressed the concern for overpressurization of containment piping penetrations following a containment isolation and subsequent heat-up. Containment isolation at all nuclear …
1
DESCRIPTION In 1977, the NRC initiated the Systematic Evaluation Program (SEP) to review the designs of 51 older, operating nuclear power plants. The SEP was divided into 2 phases. In Phase I, the staff defined 137 issues for which regulatory requirements …
1
The results of ongoing staff-sponsored research which culminated in the assessment of risk at five U.S. nuclear reactors (NUREG-1150 [1] ) indicated that, for the Peach Bottom MARK I containment, the core-melt probability was relatively low. However, it …
1
DESCRIPTION Historical Background This issue was identified [1] by NRR following a request from Region I to review GE SIL 477 which identified the possibility of early containment bypass in a BWR, if any one of the MSIVs inside containment should fail to …
1
DESCRIPTION Historical Background This issue was identified when it was believed [1] that the validity of steam generator (SG) tube leak and rupture analyses could be affected by resonance vibrations in steam generator tubes during steam line break …
1
DESCRIPTION Historical Background This generic issue was proposed [1] in response to SECY-00-198 [2] which explored means of risk informing 10 CFR 50.44. As a part of this effort, the paper recommended that safety enhancements that have the potential to …
1
DESCRIPTION Historical Background This issue was raised [1] by NRR and addresses the adequacy of the calculations, testing, and acceptance criteria related to the creation of a vacuum in the reactor building of a BWR, following an engineered safeguards …
1
DESCRIPTION Historical Background Beginning in the early-1980s, the NRC sponsored the development of a Probabilistic Seismic Hazard Analysis (PSHA) methodology by LLNL. For the purpose of conducting a systematic evaluation of the licensing criteria for …
1
DESCRIPTION On May 26, 2005, the Office of Nuclear Reactor Regulation (NRR), Division of Engineering, recommended that issues related to closed Generic Issue (GI)-194, "Implications of Updated Probabilistic Seismic Hazard Estimates," dated September 23, …
1
The Chernobyl accident, with its absence of effective containment, has focused attention on the strengths and performance limits of the substantial containments for U.S. LWRs. It has led to added recognition of the significance of ongoing work on the …
1
DESCRIPTION On May 26, 2005, the Office of Nuclear Reactor Regulation (NRR), Division of Engineering, recommended that issues related to closed Generic Issue (GI)-194, "Implications of Updated Probabilistic Seismic Hazard Estimates," dated September 23, …
1
Page Last Reviewed/Updated 3/1/2026
Disclaimer: Some of the formatting in NUREG-0933 may not be correct. We are currently working on fixing the formatting.