Document: NUREG-0800
Document ID: 4cca74ec-66e0-4765-9c61-cf547e17c308
Document Type: srp
Title: of the plant safety analysis report (SAR).  Although the NRC did not endorse the annexes of
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1601/ML16019A114.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7.6
CFR Part: 
CFR Title: 

Content:
ay be obtained from sensors, operators, other equipment, or other software. Outputs may be directed to actuators, operators, other equipment, or other software. • Reliability - The degree to which a software system or component operates without failure. This definition does not consider the consequences of failure, only the existence of failure. • Robustness - The ability of a software system or component to function correctly in the presence of invalid inputs or stressful environmental conditions. This includes the ability to function correctly despite some violation of the assumptions in its specification. • Safety - Those properties and characteristics of the software system that directly affect or interact with system safety considerations. The other characteristics discussed in SRP BTP 7-14 are important contributors to the overall safety of the software-controlled safety system, but are primarily concerned with the internal Appendix 7.1-D-9 Revision 1 - August 2016 operation of the software. The safety characteristic, however, is primarily concerned with the effect of the software on system hazards and the measures taken to control those hazards. • Security - The establishment of a secure development and operational environment (SDOE) for digital safety systems (1) to prevent undocumented, unneeded, and unwanted modifications and (2) to protect against a predictable set of undesirable acts (e.g., inadvertent operator actions or the undesirable behavior of connected systems) that could challenge the integrity, reliability, or functionality of a digital safety system during operations. RG 1.152 provides guidance on SDOE. 5.3.1.1 Software Quality Metrics (IEEE Std 7-4.3.2, Sub-Clause 5.3.1.1) Industry practice is moving towards the use of software quality metrics to ensure, monitor and improve software quality in addition to the V&V that has traditionally been applied. SRP BTP 7-14 has identified one of the characteristics to be considered during the