Document: NUREG-0800
Document ID: 9a64419a-34ff-49d2-87dd-c6f10c12014f
Document Type: srp
Title: or 7.3 of the SAR.
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0525/ML052500501.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7.2
CFR Part: 
CFR Title: 

Content:
amental requirements for this qualification process. This standard allows the use of engineering judgment for the acceptance of existing software, and the use of compensating factors to substitute for missing elements of the software development process. These provisions should not be interpreted to permit unsupported subjectivity in the acceptance of existing software. EPRI TR-106439, "Guideline on Evaluation and Acceptance of Commercial Grade Digital Equipment for Nuclear Safety Applications," provides more detail on the characteristics of an acceptable process for qualifying existing software, and discusses the use of engineering judgment and compensating factors. Programmable logic controllers (PLCs) are a possible means of implementing safety-related I&C using existing commercial computers. BTP HICB-18 describes an acceptable process for applying the recommendations of this section to PLC implementations. Rev. 4 — June 1997 SRP 7.1-6 c. Software tools — Compliance with the fundamental quality requirements necessitates that computer-based tools used in the design of digital I&C not introduce faults into the software which is resident on the computer at run time. IEEE Std 7-4.3.2, Section 5.3.3 describes an acceptable means of preventing such faults. The qualification process described in EPRI TR-106439 and the development process described in BTP HICB-14 are acceptable alternative processes for ensuring the quality of software tools is adequate to minimize the introduction of faults into plant software. d. Verification and validation — As described in Section 5.3.4 of IEEE Std 7-4.3.2, an acceptable software development process and hardware/software integration process will include verification and validation that provides adequate confidence that both the safety system requirements and those requirements defined at each stage of development, including handling of credible abnormal conditions, have been implemented. Implementation of a software engineering