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:
ortions of the system and the safety-related portions of the system being capable of 75 withstanding the effects of natural phenomena such as earthquakes, tornadoes, hurricanes, and floods, and GDC 4, "Environmental and Dynamic Effects Missile 76 77 78 Design Bases," with respect to structures housing the safety-related portions of the 79 system and the safety-related portions of the system being capable of withstanding the effects of external missiles, and internally-generated missiles, and pipe whip and jet 80 impingement forces associated with pipe breaks. The essential portions of the MSSS (as identified in the above discussion) are designed Seismic Category I and housed in a Seismic Category I structure which provides protection from the effects of tornadoes, tornado missiles, turbine missiles, and floods. This meets the positions of Regulatory Guide 1.29, "Seismic Design Classification," Position C.1.a, C.1.e, C.2 and C.3 or C.1.f, C.2 and C.3; Regulatory Guide 1.115, "Protection Against Low-Trajectory Turbine 81 Missiles," Position C.1; Regulatory Guide 1.117, "Tornado Design Classification," Appendix Positions 2 and 4. In addition, the system design capabilities should includes the capability to 82 accommodate water (steam) hammer dynamic loads resulting from rapid closure of 83 systems valves (including turbine bypass and stop valves), and safety/relief valve 84 85 operation without compromising required safety functions. Water entrainment considerations should include provisions for drain pots, line sloping and valve 86 operation. Operating and maintenance procedures are to be reviewed by the applicant to alert plant personnel to the potential for and means to minimize water (steam) hammer occurrences such occurrences and means to minimize such occurrences. This 87 commitment is should be stated in the applicants' SAR. 88 2. The applicant has met the requirements of GDC 5, "Sharing of Structures, Systems, and Components" with Rrespect to the Ccapability of