Document: NUREG-0800
Document ID: 632e6c59-03bd-4648-b0b3-e8b2efd6fa04
Document Type: srp
Title: CONTAINMENT ISOLATION SYSTEM
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0703/ML070380197.pdf
Revision Date: 2023-06
Chapter: 6
Section ID: 6.2.4
CFR Part: 
CFR Title: 

Content:
viewers responsible for the structural design of the containment internal structures and piping systems, including restraints, ensure that the containment isolation provisions are protected adequately against missiles, pipe whip, and earthquakes. The review determines whether for all containment isolation provisions, missile protection and protection against loss of function from pipe whip and earthquakes were design considerations. The system drawings (which should show the locations of missile barriers as to the containment isolation provisions) are reviewed for whether isolation provisions are protected from missiles. The design criteria for the containment isolation provisions are reviewed for whether protection against dynamic effects like pipe whip and earthquakes was considered in the design. The reviewer requests review of the design adequacy of piping and valves for which conservative design in lieu of leak-tight housing is assumed to preclude possible breach of system integrity. 3. The signals from the plant protection system to initiate containment isolation are reviewed. In general, there should be a diversity of parameters sensed (e.g., abnormal conditions in the reactor coolant system, the secondary coolant system, and the containment) generating containment isolation signals. As plant designs differ and many different signal combinations from the plant protection system initiate containment isolation, the reviewer considers proposed arrangements individually for overall acceptability of the containment isolation signals. The containment setpoint pressure that initiates containment isolation for nonessential penetrations is reviewed. This pressure setpoint should be the minimum value compatible with normal operation, as required by 10 CFR 50.34(f)(2)(xiv)(D). Additional guidance for review of this setpoint is presented in Item II.E.4.2 of NUREG-0737. 4. The reviewer verifies that the control system for automatic containment isolation valves is designed