Document: 10 CFR Part 50
Document ID: 94032a42-694d-452c-a4bf-3906aee6f0b7
Document Type: cfr
Title: Risk-informed categorization and treatment of structures, systems and components for nuclear power reactors.
Source: 10 CFR Part 50
Source URL: https://www.ecfr.gov/current/title-10/part-50/section-50.69
Revision Date: 
Chapter: 
Section ID: 50.69
CFR Part: 50
CFR Title: 10

Content:
§ 50.69 Risk-informed categorization and treatment of structures, systems and components for nuclear power reactors. ( a ) Definitions. Risk-Informed Safety Class (RISC)-1 structures, systems, and components (SSCs) means safety-related SSCs that perform safety significant functions. Risk-Informed Safety Class (RISC)-2 structures, systems and components (SSCs) means nonsafety-related SSCs that perform safety significant functions. Risk-Informed Safety Class (RISC)-3 structures, systems and components (SSCs) means safety-related SSCs that perform low safety significant functions. Risk-Informed Safety Class (RISC)-4 structures, systems and components (SSCs) means nonsafety-related SSCs that perform low safety significant functions. Safety significant function means a function whose degradation or loss could result in a significant adverse effect on defense-in-depth, safety margin, or risk. ( b ) Applicability and scope of risk-informed treatment of SSCs and submittal/approval process. ( 1 ) A holder of a license to operate a light water reactor (LWR) nuclear power plant under this part; a holder of a renewed LWR license under part 54 of this chapter ; an applicant for a construction permit or operating license under this part; or an applicant for a design approval, a combined license, or manufacturing license under part 52 of this chapter ; may voluntarily comply with the requirements in this section as an alternative to compliance with the following requirements for RISC-3 and RISC-4 SSCs: ( i ) 10 CFR part 21 . ( ii ) The portion of 10 CFR 50.46a(b) that imposes requirements to conform to Appendix B to 10 CFR part 50. ( iii ) 10 CFR 50.49 . ( iv ) 10 CFR 50.55(e) . ( v ) The inservice testing requirements in 10 CFR 50.55a(f) ; the inservice inspection, and repair and replacement (with the exception of fracture toughness), requirements for ASME Class 2 and Class 3 SSCs in 10 CFR 50.55a(g) ; and the electrical component quality and qualification requirements in