Document: NRC Regulatory Guide
Document ID: 10f3c2aa-ada2-4132-8d49-7867458d81a7
Document Type: regulatory_guide
Title: Design Limits and Loading Combinations for Metal Primary Reactor Containment System Components + HISTORY - HISTORY 10/2006 – DG-1158 , Proposed Revision 1
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML0630/ML063000278.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.57
CFR Part: 
CFR Title: 

Content:
to Level A service limits, plus the additional loads resulting from natural phenomena during which the plant must remain operational. The loading combinations corresponding to these limits include the following: (1) Loss-of-coolant accident in combination with the operating-basis earthquake D + L + Ta + Ra + Pa + E (2) Operating plant condition in combination with the operating-basis earthquake D + L + To + Ro + Po + E (3) Operating plant condition in combination with the operating-basis earthquake and multiple SRV actuations D + L + Ts + Rs + Ps + E (4) Loss-of-coolant accident in combination with a single active component failure causing one SRV discharge D + L + Ta + Pa + Ra + Ts + Rs + Ps DG-1158, Page 8 1.2.3.3 Level C Service Limits These service limits include the loads subject to Level A service limits, plus the additional loads resulting from natural phenomena for which safe shutdown of the plant is required. The loading combinations corresponding to these limits include the following: (1) Loss-of-coolant accident in combination with the SSE D + L + Ta + Ra + Pa + E’ (2) Operating plant condition in combination with the SSE D + L + To + Ro + Po + E’ (3) Multiple SRV actuations in combination with a small- or intermediate-break accident and SSE D + L + Ta + Ra + Pa + Ts + Rs + Ps + E’ (4) Dead load plus pressure resulting from an accident that releases hydrogen generated from 100% fuel clad metal-water reaction accompanied by hydrogen burning D + Pg1 + Pg2 [NOTE: In this load combination, Pg1 + Pg2 should not be less than 310 kPa (45 psig).] (5) Dead load plus pressure resulting from an accident that releases hydrogen generated from 100% fuel clad metal-water reaction accompanied by the added pressure from post-accident inerting, assuming carbon dioxide as the inerting agent D + Pg1 + Pg3 [NOTE: In this load combination, Pg1 + Pg3 should not be less than 310 kPa (45 psig).] 1.2.3.4 Level D Service Limits These service limits include other applicable