Document: NUREG-0800
Document ID: 3ab8ae04-e11b-4993-a907-f644301c5af2
Document Type: srp
Title: MAIN STEAM SUPPLY SYSTEM
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070577.pdf
Revision Date: 2023-06
Chapter: 10
Section ID: 10.3
CFR Part: 
CFR Title: 

Content:
al phenomena such as earthquakes, tornadoes, hurricanes, and floods, and the positions of the following: a. Regulatory Guide 1.29, as related to the seismic design classification of system components, Positions C.1.a, C.1.e, C.1.f, C.2, and C.3. b. SECY 93-087 (Reference 14), applicable to BWR plants that do not incorporate a main steam isolation valve leakage control system (MSIVLCS) and for which main steam line fission product hold-up and retention is credited in the analysis of design basis accident radiological consequences: (1) The main steam lines extending from the outermost containment isolation valve to the seismic interface restraint and connected piping up to the first normally closed valve are classified seismic Category I. (2) The main steam lines from the seismic interface restraint up to but not including the turbine stop valve (including connected piping to the first normally closed valve) may be classified as non-seismic Category I if the following criteria are met: DRAFT Rev. 4 - April 1996 10.3-6 i. They have been analyzed using a dynamic seismic analysis method to demonstrate their structural integrity under SSE loading conditions. ii. All pertinent QA requirements of Appendix B to 10 CFR Part 50 are applied. iii. For lines utilized as an MSIV leakage path to the condenser, reliable power sources must be available for control and isolation valves so that a control operator can establish the flow path assuming a single active failure. (3) Main steam lines and other main steam system components are assigned a quality group classification in accordance with the criteria of SRP Section 3.2.2, Appendix A.44 cb. Regulatory Guide 1.117, as related to the protection of structures, systems, and components important to safety from the effects of tornado missiles, Appendix Positions 2 and 4. 2. General Design Criterion 4, with respect to safety-related portions of the system being capable of withstanding the effects of external missiles and internally