Document: NUREG-0800
Document ID: dd4f84a9-8976-44c4-b631-d7c0254f4efc
Document Type: srp
Title: PROBABILISTIC RISK ASSESSMENT AND SEVERE ACCIDENT EVALUATION FOR
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1416/ML14161A594.pdf
Revision Date: 2023-06
Chapter: 19
Section ID: 19.0
CFR Part: 
CFR Title: 

Content:
d by the applicant. G. The PRA reviewer should evaluate the treatment of the recovery actions taken for loss of DI&C functions, referring to RG 1.200 and good practices in human reliability assessment (HRA) for additional guidance. Coordinate the review with staff evaluating areas such as main control room design, and minimum alarms and controls inventory. If recovery actions are modeled, they should consider loss of instrumentation and the time available to complete such action. H. Verify that a method for quantifying the contribution of software failures to DI&C system reliability was used and documented. I. It is important to evaluate claims by applicants regarding the credit that should be given for defensive design features. Verify that key assumptions from the DI&C PRA are captured under the applicant’s design reliability assurance program (D-RAP), which is described in SRP Chapter 17, Section 17.4. The applicant should describe adequately where and how the D-RAP captures the DI&C system key assumptions, such as how future software and hardware 6 i.e., measures that provide DI&C fault prevention, removal, and tolerance, e.g., memory allocation, network/bus design features, automatic tester system, diagnostics, and data acquisition system.. 19.0-33 Draft Revision 3 –November 2014 modifications will be conducted to ensure that high reliability and availability are maintained over the life of the plant. The following 10 additional steps, as applicable, are included if a more detailed review is needed (e.g., through field audits): A. Verify that physical and logical dependencies are identified and their bases provided in the DI&C PRA. The probabilistic model should encompass all relevant dependencies of a DI&C system on its support systems. For example, if the same DI&C hardware is used for implementing several DI&C systems that perform different functions, a failure in the hardware, software, or system of the DI&C platform may adversely affect all these