Document: NRC Regulatory Guide
Document ID: b3436475-0452-4460-897e-ef2d0023a709
Document Type: regulatory_guide
Title: Guidelines for Lightning Protection of Nuclear Power Plants (Rev. 1)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML2220/ML22208A232.pdf
Revision Date: 2023-05
Chapter: 
Section ID: RG-1.204
CFR Part: 
CFR Title: 

Content:
trical characteristics for which these DG-1409, Page 2 performance specifications can be ensured; and the environmental conditions, including temperature, pressure, humidity, radiation, chemicals, and submergence at the location where the equipment must perform as specified. o 10 CFR 50.49(b) defines electric equipment important to safety as safety-related electric equipment (Class 1E equipment in IEEE 323-1974) that is relied upon to remain functional during and following design basis events to ensure the integrity of the reactor coolant pressure boundary; the capability to shut down the reactor and maintain it in a safe shutdown condition; or the capability to prevent or mitigate the consequences of accidents that could result in potential offsite exposures. o 10 CFR Part 50, Appendix A, GDC 2, “Design Bases for Protection against Natural Phenomena,” requires, in part, that SSCs important to safety be designed to withstand the effects of natural phenomena without loss of capability to perform their safety functions. The design bases for these SSCs must reflect (1) appropriate consideration of the most severe natural phenomena that have been historically reported for the site and surrounding area, with sufficient margin for limited accuracy, quantity, and period of time in which the historical data have been accumulated; (2) appropriate combinations of the effects of normal and accident conditions with the effects of the natural phenomena; and (3) the importance of the safety functions to be performed. • 10 CFR Part 52 o 10 CFR 52.47(a)(13) requires that an applicant for a design certification must provide the list of electrical equipment important to safety as specified in 10 CFR 50.49(d). o 10 CFR 52.137(a)(13) requires that an applicant for a standard design approval must provide the list of electric equipment that is important to safety as defined by 10 CFR 50.49(d). Related Guidance • RG 1.180, “Guidelines for Evaluating Electromagnetic and