Document: NRC Regulatory Guide
Document ID: ae72d1f2-aba4-4afd-bf00-6a4263c3f3e9
Document Type: regulatory_guide
Title: Control of Heavy Loads at Nuclear Facilities
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML2100/ML21006A335.pdf
Revision Date: 2023-05
Chapter: 
Section ID: RG-1.244
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CFR Title: 

Content:
iated fuel from storage pools to dry storage and removal of the reactor vessel head and internal structures in support of refueling, which, if the load were dropped, could challenge the performance of safety functions. Other reactor types may also require load handling activities for continued operation that could similarly challenge safety functions. In addition, existing facilities were constructed without full consideration of load handling activities that could challenge safety functions in other ways. For these handling evolutions, the staff has accepted other methods of providing reasonable assurance that key safety functions would be accomplished in the event of failures affecting load handling equipment. 1 For the purpose of this RG, the fundamental safety functions are (1) control of nuclear reactivity, (2) adequate removal of heat from the reactor and from stored irradiated fuel, (3) appropriate confinement of radioactive material, and (4) maintenance of adequate shielding against radiation. DG - 1381, Page 6 of 16 The staff described these methods in NUREG-0612, which provides for the use of one of the following methods in areas where a handling system failure could challenge execution of key safety functions: use of a highly reliable handling system, verification by analysis that safety functions would be accomplished in the event of a load drop, or the use of electrical interlocks or mechanical stops to prevent the motion of loads over SSCs necessary to perform key safety functions. The guidelines in NUREG- 0612 establish the following criteria to demonstrate by analysis of load drop consequences that safety functions had been accomplished: • Releases of radioactive material result in doses well within regulatory limits. • Damage does not result in a fuel configuration with an effective neutron multiplication factor greater than 0.95. • Resulting leakage from the reactor vessel and spent fuel pool is within makeup capabilities. • At least one