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:
described in the specific RG. If the secondary reference has neither been incorporated by reference into NRC regulations nor endorsed in a RG, then the secondary reference is neither a legally-binding requirement nor a “generic” NRC-approved acceptable approach for meeting an NRC requirement. However, licensees and applicants may consider and use the information in the secondary reference, if appropriately justified, consistent with current regulatory practice, and consistent with applicable NRC requirements. DG-1409, Page 7 C. STAFF REGULATORY GUIDANCE The collective guidance in IEEE Std. 665-19951; IEEE Std. 666-2007; IEEE Std.1050-2004; IEEE C62.23-2017 provide an acceptable approach to the NRC staff for meeting the agency’s regulatory requirements for adequate lightning protection of SSCs in production and utilization facilities with the clarifications below. 1. LPSs should be inspected following installation, and systems should be inspected on a regular, periodic basis throughout their lifetime. LPS systems should be inspected whenever any alterations or repairs are made to a protected structure, as well as following any known lightning transient to the system. An LPS should be visually inspected at least annually. In areas where severe climatic changes occur, it is advisable to inspect the LPS semiannually or following extreme changes in ambient temperature. An in-depth inspection of the LPS every 3–5 years to assess the effects of aging is also recommended. 2. Testing and maintenance procedures should be established for each LPS. The frequency of testing and maintenance will depend on weather-related degradation of protective features, frequency and severity of damage attributable to lightning transients, and required protection level. Also, an LPS testing and maintenance program should include (1) inspection of all conductors and system components, (2) tightening of all clamps and splicers, (3) measurement of the earth grounding resistance, (4)