Document: NRC Regulatory Guide
Document ID: e16da529-b6b4-4fdf-bc3f-7490180363f3
Document Type: regulatory_guide
Title: Environmental Qualification of Certain Electric Equipment Important to Safety for Nuclear Power Plants (Rev. 2)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML2018/ML20183A423.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.89
CFR Part: 
CFR Title: 

Content:
recommendations do not correspond to the requirements specified in the NRC’s regulations, and the NRC’s requirements take precedence over the international guidance. DG-1361, Page 9 the secondary reference, if appropriately justified, consistent with current regulatory practice, and consistent with applicable NRC requirements. DG-1361, Page 10 C. STAFF REGULATORY GUIDANCE 1. Staff Position 1 represents the NRC’s endorsement of IEC/IEEE Std. 60780-323, Edition 1, 2016-02 with the following clarifications: a. 10 CFR 50.49(e)(5) requires, in part, that equipment qualified by test must be preconditioned by natural or artificial (accelerated) aging to its end-of-installed-life condition. Therefore, “end condition,” as defined in Section 3.10 of IEC/IEEE Std. 60780-323, Edition 1, 2016-02, should be considered equivalent to “end-of-installed life.” Note: Qualified equipment must be capable of performing its design function at the end-of-installed life. b. The following description and definition of “important to safety” should be used instead of the definition in Section 3.12 of IEC/IEEE Std. 60780-323, Edition 1, 2016-02: 10 CFR 50.49 requires safety-related electric equipment (Class 1E) as defined in 10 CFR 50.49(b)(l) to be qualified to perform its intended safety functions. Appendix A to this guide lists typical safety-related equipment and systems. 10 CFR 50.49(b)(2) requires that nonsafety-related electric equipment be environmentally qualified if its failure under postulated environmental conditions could prevent satisfactory accomplishment of the safety functions specified in 10 CFR 50.49(b)(1)(i)(A) through (C) by safety-related electric equipment. Appendix B to this guide includes typical examples of nonsafety-related electric equipment. 10 CFR 50.49(b)(3) requires that certain post-accident monitoring equipment also be environmentally qualified. RG 1.97 includes regulatory guidance for post-accident monitoring equipment. While the above