Document: NUREG-0800
Document ID: e6b7e6d3-a99d-424d-bfa0-491bc48f46cf
Document Type: srp
Title: ISOLATION CONDENSER SYSTEM (BWR)
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0708/ML070810517.pdf
Revision Date: 2023-06
Chapter: 5
Section ID: 5.4.13
CFR Part: 
CFR Title: 

Content:
uld result in potential offsite exposures comparable to the guideline exposures of 10 CFR Part 100. Because the ICS performs ECCS functions, the ICS, and structures housing the ICS, must be capable of withstanding the effects of natural phenomena. A seismic design classification system has been developed for identifying those plant features that should be designed to withstand the effects of a safe-shutdown earthquake (SSE). Regulatory Guide 1.29, Position C.1, states that systems required for safe shutdown, including their foundations and supports, are designated as Seismic Category I and should be designed to withstand the effects of the SSE and remain functional. Compliance with Regulatory Guide 1.29 provides assurance that the ICS will perform its intended safety function in the event of an earthquake. 5.4.13-9 March 2007 2. GDC 4 requires that SSCs important to safety be designed to accommodate the effects of, and to be compatible with, the environmental conditions associated with normal operation, maintenance, testing, and postulated accidents. SSCs should also be appropriately protected against dynamic effects, including the effects of missiles, pipe whipping, and discharging fluids, that may result from equipment failures and from events and conditions outside the nuclear power unit. The ICS provides DHR capacity, and the dynamic effects of water hammer could degrade system effectiveness. Compliance with GDC 4 assures that the ICS will remain functional and provide essential cooling necessary for DHR. 3. GDC 5 prohibits the sharing of SSCs among nuclear power units unless it can be shown that such sharing will not significantly impair their ability to perform their safety functions, including, in the event of an accident in one unit, an orderly shutdown and cooldown of the remaining units. The ICS provides DHR capability after the reactor is shut down and isolated. The reactor water cleanup/shutdown cooling (RWCU/SDC) system and other engineered safety