Document: NRC Regulatory Guide
Document ID: 26c3e31f-c018-4aee-b926-6db849b72a5a
Document Type: regulatory_guide
Title: Guidelines for Environmental Qualification of Safety-Related Computer-Based Instrumentation and Control Systems in Nuclear Power Plants
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML0630/ML063040591.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.209
CFR Part: 
CFR Title: 

Content:
onse for a computer-based I&C system is based on type testing of the individual modules and analysis of the cumulative effects of environmental and operational stress on the entire system. (3) Section 6.3.1.7(C) of IEEE Std. 323-2003 provides a note to the standards applicable to testing for electromagnetic interference/radio frequency interference (EMI/RFI) and surge as environmental conditions. Guidelines for conducting electromagnetic susceptibility testing of safety-related I&C systems appear in Revision 1 of Regulatory Guide 1.180, “Guidelines for Evaluating Electromagnetic and Radio-Frequency Interference in Safety-Related Instrumentation and Control Systems,” issued October 2003, and in Revision 1 of EPRI TR 102323, “Guidelines for Electromagnetic Interference Testing in Power Plants,” as endorsed in a related SER dated April 17, 1996. (4) For safety-related computer-based I&C systems intended for implementation in a mild environment, the NRC staff takes exception to Section 7.1 of IEEE Std. 323-2003. The evidence of qualification in a mild environment should be consistent with the guidance given in Section 7.2 selectively based on actual environmental conditions and should be retained at the facility in an auditable form. (5) Regulatory Guide 1.89 offers guidance for the environmental qualification of electrical equipment located in a harsh environment, as required by 10 CFR 50.49. For safety-related computer-based I&C systems installed in a harsh environment, the regulatory positions of this guide supplement the harsh environment qualification practices endorsed in Regulatory Guide 1.89. DG-1142, Page 8 D. IMPLEMENTATION The purpose of this section is to provide information to applicants and licensees regarding the NRC staff’s plans for using this draft regulatory guide. This guide applies to new plants and its use is voluntary for modifications at plants that are operating in 2006. No backfitting is intended or approved in connection with its