Document: NRC Regulatory Guide
Document ID: 2980f2d9-2e7d-4afa-9e1f-a8abe5fb7507
Document Type: regulatory_guide
Title: Software Requirement Specifications for Digital Computer Software and Complex Electronics Used in Safety Systems of Nuclear Power Plants + HISTORY - HISTORY 08/2012 – DG-1209 , Proposed Revision 1 08/1996 – DG-1058 , Proposed Revision 0 (Rev. 1)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML1030/ML103080963.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.172
CFR Part: 
CFR Title: 

Content:
s must be available either in the SRS itself or in a glossary. g. Traceability. In accordance with GDC 1 of Appendix A to 10 CFR Part 50 and as described in Subclause 4.3.8 of IEEE Std. 830-1998, each identifiable requirement in an SRS must be backward traceable to a higher level requirements specification and ultimately to the system licensing (e.g., regulatory requirements that it satisfies) and the design bases (e.g., IEEE 603-1991 Clause 4). Each identifiable requirement should be written so that it can also be forward traceable to subsequent design outputs (e.g., from SRS to software design and from software design to SRS). Forward traceability to all documents derived from the SRS includes verification and validation materials. For example, a forward trace should exist from each requirement in the SRS to the specific inspections, analyses, or tests used to confirm that the requirement has been met. h. Unambiguity. Subclause 4.3.2 of IEEE Std. 830-1998 states that an SRS is unambiguous if, and only if, every requirement has only one interpretation. Software products and system products are generally derived from software requirements. The relationships established between software requirements and the products that they are used to create should be unambiguous. DG-1209, Page 8 3. Change Control in Software Requirement Specifications Subclause 4.5(b) of IEEE Std. 830-1998 recommends that SRSs be baselined and subject to a formal process for the control of changes. Although the licensee or applicant should meet this recommendation directly through a change control procedure unique to IEEE Std. 830-1998, it may also meet it by placing the SRS under a general software configuration management program as a configuration item. Regulatory Guide 1.169 discusses software configuration management and endorses IEEE Std. 828-2005, “IEEE Standard for Software Configuration Management Plans,” issued 2005 (Ref. 20). 4. Incomplete Software Requirement Specifications Entry