Document: NUREG-0800
Document ID: 65f2433f-2c4a-4580-b173-0c6da7fa4d73
Document Type: srp
Title: Draft Revision 7 – August 2015
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1515/ML15159A996.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7
CFR Part: 
CFR Title: 

Content:
acceptability criteria (see Section 3.5, “Use of Manual Action as a Diverse Means of Accomplishing Safety Functions” below). (8) If the D3 assessment reveals a potential for a CCF, then the method for accomplishing the diverse means of actuating the protective safety functions should meet the following criteria: The diverse means should be: a) at the system or division level (depending on the design); b) initiated from the control room; c) capable of responding with sufficient time available for the operators to determine the need for protective actions even with indicators that may be malfunctioning due to the CCF if credited in the D3 coping analysis; d) appropriate for the event; e) supported by sufficient instrumentation that indicates: 1. the protective function is needed, 2. the safety-related automated system did not perform the protective function, and 3. whether the automated diverse means or manual action is successful in performing the safety function. (9) If the D3 assessment reveals a potential for a CCF, then, in accordance with the augmented quality guidance for the diverse means used to cope with a CCF, the design of a diverse automated or diverse manual actuation system should address how to minimize the potential for a spurious actuation of the protective system caused by the diverse means. Use of design techniques (for example, redundancy, conservative setpoint selection, coincidence logic, and use of quality components) to mitigate these concerns is recommended. The adequacy of the diversity provided with respect to the above criteria should be justified by the applicant and explicitly addressed in the staff’s safety evaluation. 3.2 RTS and ESFAS Interconnection Interconnections between the RTS and ESFAS (for interlocks providing for reactor trip if certain ESFs are initiated, ESF initiation when a reactor trip occurs, or operating bypass functions) are permitted if it can be demonstrated that the functions required by the ATWS rule (10 CFR