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
CFR Part: 
CFR Title: 

Content:
wing three ASME Standards, with the clarifications stated below: • ASME Std. NML-1, “Rules for the Movement of Loads Using Overhead Handling Equipment in Nuclear Facilities” • ASME Std. NOG-1, “Rules for Construction of Overhead and Gantry Cranes (Top Running Bridge, Multiple Girder)” • ASME Std. BTH-1, “Design of Below-the-Hook Lifting Devices,” in part, only Chapters 1 through 3. Regulatory Position C.1 1. This RG endorses ASME Std. NML-1-2019 as acceptable guidance for establishing a nuclear facility heavy load handling program, subject to the following clarifications: a. In regard to Section 2-6.1(c)(1) of ASME Std. NML-1, if handling-system-controlled range of motion is credited to ensure that essential safety functions would be maintained, then the evaluation of handling system controls for range of motion should include the following considerations: (1) Boundaries of the range of motion should include the following specific factors: • a margin for tipping equal to the height of the load when the characteristics of planned handling system lifts include a load with a center of gravity higher than the width of its base in its planned handling orientation; and • exclusion of components from within the range of motion when secondary effects from that component’s failure (e.g., flooding from pressurized piping that could credibly cause failure of equipment outside the boundary) would prevent performance of an essential safety function; and (2) administrative measures should prevent unintended disabling of the range of motion controls when they are not a permanent feature of the design (e.g., key-operated bypass of electrical motion interlocks). b. In regard to Section 2-6.1(c)(2) of ASME Std. NML-1, if enhanced handling system reliability is credited to ensure essential safety functions would be maintained, then the handling system design should meet the crane and lifting device standards by conforming to the following guidelines: (1) The