Document: NUREG-0800
Document ID: fea61ff0-f344-4101-adfb-590e3d9dfafe
Document Type: srp
Title: Draft Revision 6 – August 2015
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1515/ML15159A946.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7
CFR Part: 
CFR Title: 

Content:
nder configuration management. (4) Examining the engineering cross-discipline interfaces to ensure that nuclear specific needs were correctly incorporated into the code. (5) Examining the applicant or licensee interface to ensure plant specific requirements are correctly incorporated. (6) Ensuring that the V&V process is followed according to the vendor's plan. (7) Reviewing the final results of the process. There may be other items in the thread audit, depending on the software tools used and the exact nature of the programing requirements and the methods. The reviewer should not hesitate to ask why something was done in a particular manner, and to use experience and judgment to assess the answer. BTP 7.14-46 Draft Revision 6 - August 2015 If errors are found, the appropriate V&V records should be examined to see if the V&V team has also caught the errors. If the requirements, code and test have been verified and validated without finding the error, a serious quality problem may exist. Additional requirements should then be checked to see if this is a systematic or an isolated problem. If several of these problems exist, the adequacy of the software development process may be insufficient to produce high quality software for use in safety-related applications in nuclear power plants. The reviewer should discuss these concerns with management to determine if the applicant or licensee request to use this software should be rejected. A successful thread audit necessitates that the reviewer be familiar with the various plans and procedures used for the software development and life cycle, and the various NRC requirements, NUREGs, RGs, and industry standards that those plans and procedures are based upon. This knowledge is necessary to be able to determine if the methodologies examined during the thread audit are those which the software developer committed to using, and if they are being used correctly. The thread audit is one of the few times where the reviewer can