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:
lity’s safety analysis report or should be consistent with the primary coolant specific activity limits contained in the facility’s technical specifications. The use of equilibrium primary coolant concentrations based on 1 percent of fuel cladding failures would be one acceptable method. In addition to sources resulting from fuel cladding failures, any additional sources of radiation exposure to the equipment should be considered if the source is of significance to the calculated normal operational dose. In estimating the integrated dose from prior normal operations, appropriate historical dose rate data may be used where available. The period of exposure for a normal operational dose is generally the duration of the plant license. Neutron radiation should be appropriately considered for equipment near the core or that may be otherwise exposed to neutron radiation. Beta radiation normally need not be considered during normal operation, except for equipment in locations where beta radiation could be a significant contributor to the radiation dose (e.g., equipment that may be located inside a high gaseous radiation source). Shielded components need not be qualified to the beta radiation environment, provided that it can be demonstrated that the sensitive portions of the component or equipment are not exposed to significant beta radiation dose rates or that the effects of beta radiation, including heating and secondary radiation, have no deleterious effects on component performance. The radiation exposure associated with maintenance, refueling, and anticipated operational occurrences (e.g., fuel transfer and resin sluicing) should be included in the normal operational dose for equipment exposed to additional radiation during or following these activities. DG-1361, Appendix D, Page D-2 The amount of dose contributed by each of these sources depends on the location of the equipment, the time-dependent and location-dependent distribution of the source, and the effects