Document: NUREG-0800
Document ID: a5f6fd7c-4062-40ac-b548-0ddba421091d
Document Type: srp
Title: ENVIRONMENTAL QUALIFICATION OF MECHANICAL AND ELECTRICAL
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0636/ML063600397.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.11
CFR Part: 
CFR Title: 

Content:
n a regulatory guide, licensees and applicants may consider and use the information in the referenced standard, if appropriately justified, consistent with current regulatory practice. 3.11-7 Revision 3 - March 2007 1. NUREG-0588, ?Interim Staff Position on Environmental Qualification of Safety Related Electrical Equipment,” Revision 1, July 1981 provides staff positions applicable to existing plants for assessing the compliance of an environmental qualification program with 10 CFR 50.49. For future plants, Regulatory Guide 1.89 provides the principal guidance for implementing the requirements and criteria of 10 CFR 50.49 for environmental qualification of electrical equipment that is important to safety and located in a harsh environment. However, certain NUREG-0588 Category I guidance may be used if relevant guidance is not provided in Regulatory Guide 1.89. NUREG-0588 includes two sets of qualification criteria, Category I and Category II. Category I refers to IEEE Std 323-1974, "IEEE Standard for Qualifying Class 1E Equipment for Nuclear Power Generating Stations." Category I applies to plants whose CP SERs were dated after July 1, 1974. Category II refers to IEEE Std 323-1971, and is not applicable to any future plants. 2. IEEE Std 323 contains the principles and criteria that are generic to the environmental qualification process. The following clarification related to the criteria in IEEE Std 323 should be considered. IEEE Std 323 requires that the service environment, including the installed configuration of the equipment, be considered as part of the qualification process. In meeting this requirement, the potential for flooding of electrical equipment that are installed above the flood level, but are subject to water and moisture intrusion, should be considered as part of environmental qualification. Operating experience (e.g., Information Notice 89-63) shows that electrical enclosures that are located above the flood level and are subject to water and