Document: NUREG-0800
Document ID: 4865fc6d-b85f-4173-9bca-162fa9fe67d2
Document Type: srp
Title: Appendix 7-A
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0525/ML052500555.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7
CFR Part: 
CFR Title: 

Content:
se, software-based digital equipment that performs the coordinated actuation logic. These displays may include digital components that are exclusively dedicated to the display function. The functional characteristics (e.g., range, accuracy, time response) of the displays provided should be sufficient to provide operators with the information needed to place and maintain the plant in a hot-shutdown condition. Human-factors engineering principles and criteria should be applied to the selection and design of the displays and controls. The human-performance requirements should be described and related to the plant safety criteria. Recognized human-factors standards and design techniques should be employed to support the described human-performance requirements. 4. Review Procedures The applicant/licensee's D-in-D&D analysis is reviewed against the above acceptance criteria using the detailed guidance of NUREG/CR-6303. Emphasis should be given to the following topics: System Representation as Blocks The system being assessed is represented as a block diagram; the inner workings of the blocks are not necessarily shown. Diversity is determined at the block level. Documentation of Assumptions Assumptions made to compensate for missing information in the design description materials or to explain particular interpretations of the analysis guidelines as applied to the system are documented by the applicant/licensee. Identification of Alternate Trip or Initiation Sequences Thermal-hydraulic analyses, using best-estimate (realistic assumptions) methods, of the sequence of events that would occur if the primary trip channel were to fail to trip the reactor or actuate ESF are included in the Appendix 7-A Rev. 4 — June 1997 BTP HICB-19-7 assessment. (Coordination with the Reactor Systems Branch, the Mechanical Engineering Branch, and the Materials and Chemical Engineering Branch is necessary in reviewing these analyses.) Identification of Alternative Mitigation Capability For