Document: NRC Regulatory Guide
Document ID: 086612c4-a8a7-4f50-a166-6f1cb05bcdaf
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:
ng the qualification process and its evidence for emerging technologies or commercially dedicated computers. Furthermore, if no action is taken, comprehensive guidance on the acceptable use of current versions of the national qualification standards will still be lacking. 2.2 Alternative 2: Enhance Current Qualification Approaches The staff considered a second alternative, which would involve enhancing current qualification approaches on the basis of the unique features of computer-based I&C systems. This alternative consists of two elements, specifically (1) assurance of a minimum level of IC component qualification based on demonstrated capability of the subcomponents to meet the performance requirements and (2) minimization (through design) of the potential effect of environmental stressors on the equipment throughout its service life. The first element involved identifying the tests that IC manufacturers employ to control quality and qualify their products for an extensive range of application environments. This approach emphasizes a “built in” philosophy as well as a “tested in” philosophy for quality and environmental compatibility. The second element of this approach used multitiered protection to establish environmental compatibility through implementations that minimize or counteract potential environmental stresses. This sound engineering practice minimizes environmental susceptibility. This approach is successful if the technology has matured for producing reliable components to meet the performance requirements. 2.3 Alternative 3: Use Tailored Endorsement of Existing Environmental Qualification Standards As a third alternative, the NRC staff considered tailored endorsement of existing qualification standards. This option would enable the NRC staff, applicants, and licensees to benefit from the existing national consensus standard. Toward that end, the staff compared different versions of qualification standards to determine how the latest updates