Document: NUREG-0800
Document ID: eb937958-fe7c-410a-91e3-63f04734878a
Document Type: srp
Title: MAIN STEAM ISOLATION VALVE LEAKAGE CONTROL SYSTEM (BMR)
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052350465.pdf
Revision Date: 2023-06
Chapter: 6
Section ID: 6.7
CFR Part: 
CFR Title: 

Content:
ulations or functional testing to demonstrate that the above conditions are met. 4. The MSIVLCS is reviewed to verify that instrumentation, controls, and inter- locks designed to standards appropriate for an engineered safety feature are provided to actuate the system in the event of a design basis LOCA, and to prevent inadvertent actuation. Interlocks to prevent inadvertent operation of the leakage control system that are actuated by signals from the reactor protection, engineered safety feature, or containment isolation systems are acceptable. A statement in the SAR that such instrumentation, controls, and interlocks will be provided is acceptable for construction permit (CP) review. 5. The system performance requirements, P&IDs, MSIVLCS drawings, and the results of failure modes and effects analyses are reviewed to assure that the system can function following a design basis LOCA assuming a concurrent single active failure, including the failure of a single main steam isola- tion valve to close. The reviewer evaluates the analyses presented in 6.7-5 Rev. 2 - July 1981 the SAR to assure the function of required components, traces the avail- ability of these components on system drawings, and checks that the SAR contains verification that minimum requirements are met for each failure condition over the required time spans. For each case the design is acceptable if minimum system functional requirements are met. The reviewer upon request from AEB provides an estimate of the quantity of fluid pro- cessed by the MSIVLCS, for use in calculating radiological consequences of a LOCA. 6. Tne leakage control system design is reviewed to verify that valve stem packing leakage or other direct leakage from the main steam isolation valves or other components outside containment is prevented or controlled. Such leakage could bypass the leakage control. system and result in untreated releases to the environment. The means for prevention or control need not be part of the leakage