Document: NUREG-0800
Document ID: c90016c6-e03f-4224-8ff3-87a6f7d3ca42
Document Type: srp
Title: Appendix 7-A
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0525/ML052500547.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7
CFR Part: 
CFR Title: 

Content:
should be specified. The detailed design documentation should contain the rationale for design decisions. Programming language standards should be identified. The detailed design documentation should identify those language features which will not be used without justification. Traceability requires that a two-way trace exist between the elements of the detailed design and the elements in the architecture. A two-way trace should exist between the detailed design elements and the code elements. There should be a forward trace from each detailed design element to the specific inspections, analyses, or tests that will be used to confirm that the element has been correctly designed. Verifiability requires that it be possible to construct specific analyses, reviews, and tests to verify that the design satisfies the software architecture. d. Implementation Activities & Code Listings A software implementation (code) should be produced. The code should include all of the functional and software development process characteristics listed below. Functional Characteristics For each of the functional characteristics, the requirements imposed on the software for that characteristic should be satisfied by the code. Functional characteristics addressed by the code documents should include accuracy, robustness, safety, and timing. Accuracy requires that the actual source code be written so that the accuracy requirements and accuracy design specifications are met. In particular, special care should be taken for floating point arithmetic, round-off errors, and the retention of precision during numerical operations. If mathematical subroutine libraries are used, the accuracy characteristics of the subroutines should be known and documented, and shown to meet the accuracy requirements and accuracy design specifications. Robustness requires that the system be coded in such a way that corrupted data will not cause the safety system to fail. Data corruption should be avoided. All input