Document: NUREG-0800
Document ID: 4f141c71-35ca-4353-9047-a13efe6d56b7
Document Type: srp
Title: Revision 6 - August 2016
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1601/ML16019A308.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7
CFR Part: 
CFR Title: 

Content:
h shows how each requirement is tested. B.3.3 Acceptance Criteria for Design Outputs This subsection describes the criteria to be used to determine whether the software has each of the characteristics important to safety system software. Criteria are organized first by life cycle activity group, then by design output, and then by characteristic. Formal or semiformal methods are available for use in preparing some of the design outputs described in this subsection. Subsection C.3 of SRP Appendix 7.0-A describes the benefits of using such methods and the precautions that should be observed when reviewing design outputs prepared with such methods. Acceptance criteria are divided into two sets: functional characteristics and process characteristics, as shown in the following table. Not all characteristics occur for every design output. Functional Process Characteristics Characteristics Accuracy Completeness Functionality Consistency Reliability Correctness Robustness Style Safety Traceability Security Unambiguity Timing Verifiability Functional Characteristics Certain system level functional criteria are required by 10 CFR 50.55a(h), and these shall be supported by the software. The following paragraphs define the acceptance criteria for the functional characteristics for safety system software. Accuracy - These accuracy values should also be used in setpoint determination calculations. Functionality - The functionality of the proposed system shall be compared to the plant requirements. The overall system, hardware and software architecture needs to be evaluated to ensure that the functionality requirements can be met. BTP 7.14-52 Revision 6 - August 2016 Reliability - The reliability of software based digital systems is difficult to determine, and to date, the state-of-the-art is such that no consensus exists on software reliability prediction methods. Care must be taken when crediting any reliability values. Robustness - The robustness of a software system needs to be