Document: NUREG-0800
Document ID: 4e771d51-141e-46e6-8ec9-fd098a4b1db7
Document Type: srp
Title: STRUCTURES, SYSTEMS, AND COMPONENTS TO BE PROTECTED FROM
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0704/ML070460362.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.5.2
CFR Part: 
CFR Title: 

Content:
e chosen design basis reflects the importance of the safety functions to be performed. RG 1.13 describes a method acceptable to the NRC staff for protecting spent fuel pool systems and structures from externally-generated missiles and preventing mechanical damage to the spent fuel by designing the facility to prevent externally-generated missiles from contacting the spent fuel within the pool. Identification of systems and structures that prevent mechanical damage to the spent fuel properly designates SSCs to be protected from externally-generated missiles. RG 1.27 describes a method acceptable to the NRC staff for protecting the ultimate heat sink and its conduits from the effects of externally-generated missiles. The ultimate heat sink constitutes the source of water supply necessary to safely operate, shut down, and cool down a nuclear plant. Because the ultimate heat sink is important to safety, its important safety-related SSCs should be identified and their safety functions secured. Protecting the ultimate heat sink SSCs important to safety from externally-generated missiles ensures that the system can perform its safety functions. Protecting important safety-related SSCs from externally-generated missiles secures such safety functions of those SSCs as maintenance of the integrity of the spent fuel pool, mitigation of the potential release of fission products, and preservation of the capability of the ultimate heat sink to maintain the plant in a safe condition. 2. GDC 4 establishes requirements for the protection of important safety-related SSCs from dynamic effects, including the effects of missiles from events and conditions outside the nuclear unit. Dynamic events originating outside the nuclear unit have the potential to generate missiles; therefore, this criterion applies directly to the assessment of important safety-related SSCs that may be affected. RG 1.115 describes methods acceptable to the NRC staff for identification and protection of important