Document: NUREG-0800
Document ID: 5cdeed4a-6cd5-4840-90c0-5159fbf2c9f0
Document Type: srp
Title: CHILLED WATER
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1409/ML14093A350.pdf
Revision Date: 2023-06
Chapter: 9
Section ID: 9.2.7
CFR Part: 
CFR Title: 

Content:
re tornado-, missile-, and flood-protected or that system components are located in individual cubicles or rooms that withstand both flooding and missiles is acceptable. The location and design of the system, structures, and pump rooms (cubicles) are reviewed for whether the degree of protection is adequate. RTNSS B: applies. RTNSS B SSCs are considered risk-significant. RTNSS B SSCs do not need to operate during accident conditions, but are required to operate in the post-72 hour period. RTNSS B SSCs are analyzed and designed to withstand adverse effects associated with internal hazards, i.e., those created from conditions inside the plant (e.g., turbine missiles, pipe whipping, and flooding). Replace paragraph 7.B. with the following: Important chilled water system portions are protected from the effects of floods, hurricanes, tornadoes, and internally- or externally-generated missiles. Flood protection and missile protection criteria are evaluated in detail under the SRP sections for SAR Chapter 3. The reviewer uses the procedures in these SRP sections to ensure that the analyses presented are valid. A finding that the system is located in a seismically qualified Category I structure that is tornado-, missile-, and flood-protected or that system components are located in individual cubicles or rooms that withstand both flooding and missiles is acceptable. The location and design of the system, structures, and pump rooms (cubicles) are reviewed for whether the degree of protection is adequate. 9.2.7-25 Draft Revision 0 – July 2014 RTNSS C: applies. RTNSS C SSCs do not need to operate during accident conditions, but are relied upon in order to meet NRC safety goals guidelines. Replace paragraph 7.B. with the following: Defense-in-depth chilled water system portions may be protected from the effects of floods, hurricanes, tornadoes, and internally- or externally-generated missiles. Flood protection and missile protection criteria are evaluated in detail under the