Document: NUREG-0800
Document ID: aa1c1ded-ea20-4e56-972b-84806f488df7
Document Type: srp
Title: RELIABILITY ASSURANCE PROGRAM
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1235/ML12354A592.pdf
Revision Date: 2023-06
Chapter: 17
Section ID: 17.4
CFR Part: 
CFR Title: 

Content:
nt operations. • The frequency of transients that challenge these SSCs is minimized. • These SSCs will function reliably when challenged. The RAP is implemented in two stages. The first stage, the design reliability assurance program (D-RAP), encompasses reliability assurance activities that occur before initial fuel load. The second stage is comprised of the reliability assurance activities conducted during the operations phase of the plant’s life cycle. The objective of the D-RAP is to ensure that the plant is designed and constructed in a manner that is consistent with the risk insights and key assumptions (e.g., SSC design, reliability, and availability) from probabilistic, deterministic, and other methods of analysis used to identify and quantify risk.1 Therefore, the key features of the D-RAP include the following: • Apply the implementation controls2 of D-RAP (i.e., organization, design control, procedures and instructions, records, corrective actions, and audit plans) during design and construction activities. These implementation controls are processes and controls that ensure the risk insights and key assumptions are consistent with the plant design 1 D-RAP should not be interpreted as a numerical analysis that would require the estimated reliability of each as-built RAP SSC to be at least equal to the reliability assumed in the PRA. D-RAP should not be based solely on numerical values. For one reason, the estimated reliability of each as-built RAP SSC and the reliability assumed in the PRA may be highly uncertain. For another, the basis for the estimated reliability of each as-built RAP SSC may be the same as, or very similar to, the basis for the reliability assumed in the PRA. Therefore, only calculating and comparing numerical values may not be useful. Finally, additional aspects of D-RAP should be considered in order to address other risk insights and key assumptions, which are not reliability values, from probabilistic, deterministic, and