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
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CFR Title: 

Content:
latory guide are equivalent to, and consistent with, those described in the EPRI TR. The primary distinctions between the two methods are that the scope of this regulatory guide focuses exclusively on environmental qualification, while the EPRI report covers a more extensive scope (e.g., platform evaluation, selection, procurement, qualification, and quality assurance); this regulatory guide addresses all safety-related computer-based I&C systems, while the EPRI report focuses on PLC platforms; and this regulatory guide endorses the current national qualification standard, while the EPRI report provides guidance based on a previous version of the national qualification standard (i.e., IEEE Std. 323-1983, “IEEE Standard for Qualifying Class 1E Equipment for Nuclear Power Generating Stations”). DG-1142, Page 3 The qualification practices endorsed in this regulatory guide are based on the current consensus national standard and employ sound engineering practices for ensuring environmental compatibility of a computer-based I&C system with the environment in which it operates. These practices apply to safety-related computer-based I&C systems intended for implementation in mild environments within a nuclear power plant. The NRC gives the technical basis for the selection of these particular practices in NUREG/CR-6479, “Technical Basis for Environmental Qualification of Microprocessor-Based Safety-Related Equipment in Nuclear Power Plants,” issued January 1998. The following related publications include supporting technical findings that were considered in determining the qualification needs for safety-related computer-based I&C systems: • NUREG/CR-5904 • NUREG/CR-6406, “Environmental Testing of an Experimental Digital Safety Channel,” issued September 1996 • NUREG/CR-6476, “Circuit Bridging of Components by Smoke,” issued October 1996 • NUREG/CR-6543, “Effects of Smoke on Functional Circuits,” issued October 1997 • NUREG/CR-6579, “Digital