Document: NUREG-0800
Document ID: d52a97d0-a519-4817-9ad6-64d94c9518af
Document Type: srp
Title: DATA COMMUNICATION SYSTEMS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1515/ML15159B177.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7.9
CFR Part: 
CFR Title: 

Content:
ses, the staff concludes that the protection systems, including the DCS, are designed to fail into a safe mode if a condition such as disconnection of the system, loss of energy, or postulated adverse environment is experienced. Therefore, the staff finds that the DCS satisfies the requirements of GDC 23. Based on the review of the interfaces between the DCS and plant operating control systems, the staff concludes that the system satisfies the requirements of (IEEE Std 279-1971 or IEEE 7.9-11 Draft Revision 6 - August 2015 Std 603-1991) with regard to control and protection system interactions. Therefore, the staff finds that the DCS satisfies the requirements of GDC 24. Based on the review of all the above, the staff concludes that the DCS satisfies the requirements of GDC 29. The staff’s conclusions noted above are based on the requirements of (IEEE Std 279-1971 or IEEE Std 603-1991) with respect to the design of the DCS. Therefore, the staff finds that the DCS satisfies the requirement of 10 CFR 50.55a(h) with regard to (IEEE Std 603-1991 or IEEE Std 279-1971). Additional evaluation findings applicable to all DCSs that support the following functions: safe shutdown systems (SRP Section 7.4), information systems important to safety (SRP Section 7.5), or interlock systems important to safety (SRP Section 7.6): Based on the staff’s review, the staff concludes that DCSs used in the [safe shutdown system, information systems important to safety, or interlock systems important to safety], taken in context with other provisions of the design, transmit the variables and commands necessary to maintain the fission process, the integrity of the reactor core, the reactor coolant pressure boundary, and the containment and its associated systems within prescribed operating ranges during plant shutdown. Therefore, the staff finds that the DCSs employed by the (safe shutdown system, information systems important to safety, or interlock systems important to safety) satisfy