DG-1175, Page 1 

U.S. NUCLEAR REGULATORY COMMISSION May 2008

OFFICE OF NUCLEAR REGULATORY RESEARCH Division 1

DRAFT REGULATORY GUIDE 

Contact: C. Ng

(301) 415-8054

DRAFT REGULATORY GUIDE DG-1175 

(Proposed Revision 3 of Regulatory Guide 1.100, dated June 1988) 

SEISMIC QUALIFICATION OF ELECTRIC AND ACTIVE 

MECHANICAL EQUIPMENT AND FUNCTIONAL 

QUALIFICATION OF ACTIVE MECHANICAL EQUIPMENT FOR 

NUCLEAR POWER PLANTS 

A. INTRODUCTION 

This guide describes methods that the staff of the U.S. Nuclear Regulatory Commission (NRC) 

considers acceptable for use in seismic qualification of electric and active mechanical equipment and 

functional qualification of active mechanical equipment for nuclear power plants (NPPs).

For seismic qualification of electric and active mechanical equipment, the general requirements 

appear in Title 10, Part 50, “Domestic Licensing of Production and Utilization Facilities,” of the Code of 

Federal Regulations (10 CFR Part 50) (Ref. 1) and 10 CFR Part 52, “Early Site Permits; Standard Design 

Certifications; and Combined Licenses for Nuclear Power Plants.” (Ref. 2) Particular sections include 

General Design Criterion (GDC) 1, “Quality Standards and Records,” GDC 2, “Design Bases for 

Protection Against Natural Phenomena,” and GDC 4, “Environmental and Dynamic Effects Design 

Basis,” of Appendix A, “General Design Criteria for Nuclear Power Plants,” to 10 CFR Part 50; Criterion 

III, “Design Control,” Criterion XI, “Test Control,” and Criterion XVII, “Quality Assurance Records,” of 

This regulatory guide is being issued in draft form to involve the public in the early stages of the development of a regulatory 

position in this area. It has not received final staff review or approval and does not represent an official NRC final staff position. 

Public comments are being solicited on this draft guide (including any implementation schedule) and its associated regulatory 

analysis or value/impact statement. Comments should be accompanied by appropriate supporting data. Written comments may 

be submitted to the Rulemaking, Directives, and Editing Branch, Office of Administration, U.S. Nuclear Regulatory 

Commission, Washington, DC 20555-0001; emailed to NRCREP@nrc.gov; submitted through the NRC’s interactive rulemaking 

Web page at http://www.nrc.gov; faxed to (301) 415-5144; or hand-delivered to Rulemaking, Directives, and Editing Branch, 

Office of Administration, US NRC, 11555 Rockville Pike, Rockville, Maryland 20852, between 7:30 a.m. and 4:15 p.m. on 

Federal workdays. Copies of comments received may be examined at the NRC’s Public Document Room, 11555 Rockville Pike, 

Rockville, MD. Comments will be most helpful if received by July 11, 2008. 

Electronic copies of this draft regulatory guide are available through the NRC’s interactive rulemaking Web page (see above); the 

NRC’s public Web site under Draft Regulatory Guides in the Regulatory Guides document collection of the NRC’s Electronic 

Reading Room at http://www.nrc.gov/reading-rm/doc-collections/; and the NRC’s Agencywide Documents Access and 

Management System (ADAMS) at http://www.nrc.gov/reading-rm/adams.html, under Accession No. ML072620346. 
DG-1175, Page 2 

Appendix B, “Quality Assurance Criteria for Nuclear Power Plants and Fuel Reprocessing Plants,” to 

10 CFR Part 50; and Appendix S, “Earthquake Engineering Criteria for Nuclear Power Plants,” to 

10 CFR Part 50. 

Section III, “Definitions,” of Appendix S to 10 CFR Part 50 states that the structures, systems, and 

components (SSCs) required to withstand the effects of the safe-shutdown earthquake (SSE) ground 

motion or surface deformation are those necessary to assure (1) the integrity of the reactor coolant pressure 

boundary; (2) the capability to shut down the reactor and maintain it in a safe-shutdown condition; or 

(3) the capability to prevent or mitigate the consequences of accidents that could result in potential offsite 

exposures comparable to the guideline exposures of 10 CFR 50.34(a)(1). Section IV(a)(1)(ii) of 

Appendix S to 10 CFR Part 50 requires that the NPP must be designed so that, if the SSE ground motion 

occurs, certain SSCs will remain functional and within applicable stress, strain, and deformation limits. In 

addition to seismic loads, the design of these safety-related SSCs must take into account applicable 

concurrent normal operating, functional, and accident-induced loads. Section IV (a)(1)(iii) of Appendix S 

to 10 CFR Part 50 requires that the safety functions of SSCs must be assured during and after the vibratory 

ground motion associated with the SSE ground motion through design, testing, or qualification methods.1

The general requirements for functional qualification of active mechanical equipment also appear 

in 10 CFR Part 50 and 10 CFR Part 52. In 10 CFR Part 50, particular sections include GDC 1, “Quality 

Standards and Records,” GDC 4, “Environmental and Dynamic Effects Design Basis,” GDC 14, “Reactor 

Coolant Pressure Boundary,” GDC 15, “Reactor Coolant System Design,” GDC 30, “Quality of Reactor 

Pressure Boundary,” GDC 37, “Testing of Emergency Core Cooling System,” GDC 40, “Testing of 

Containment Heat Removal System,” GDC 43, “Testing of Containment Atmosphere Cleanup Systems,” 

GDC 46, “Testing of Cooling Water Systems,” and GDC 54, “Piping Systems Penetrating Containment,” 

of Appendix A to 10 CFR Part 50, as well as Criteria III, XI, and XVII of Appendix B to 10 CFR Part 50. 

The NRC issues regulatory guides to describe to the public methods that the staff considers 

acceptable for use in implementing specific parts of the NRC regulations, to explain techniques that the 

staff uses in evaluating specific problems or postulated accidents, and to provide guidance to applicants. 

Regulatory guides are not substitutes for regulations and compliance with them is not required. 

This regulatory guide contains information collection requirements covered by 10 CFR Part 50 and 

10 CFR Part 52, and that the Office of Management and Budget (OMB) approved under OMB control 

numbers 3150-0011 and 3150-0151. The NRC may neither conduct nor sponsor, and a person is not 

required to respond to, an information collection request or requirement unless the requesting document 

displays currently valid OMB control numbers. 

 

1

 Appendix S to 10 CFR Part 50 applies to applicants for a design certification or combined license pursuant to 

10 CFR Part 52 or a construction permit or operating license pursuant to 10 CFR Part 50 after January 10, 1997. 

However, the earthquake engineering criteria in Section VI, “Application to Engineering Design,” of Appendix A, 

“Seismic and Geologic Siting Criteria for Nuclear Power Plants,” to 10 CFR Part 100, “Reactor Site Criteria,” 

continue to apply for either an operating license applicant or holder with a construction permit issued before 

January 10, 1997. 
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B. DISCUSSION

Background 

The NRC issued Revision 2 of Regulatory Guide 1.100, “Seismic Qualification of Electric and 

Mechanical Equipment for Nuclear Power Plants,” (Ref. 3) in June 1988. With a few exceptions and 

clarifications, it endorsed the Institute of Electrical and Electronics Engineers (IEEE) Std 344-1987, “IEEE 

Recommended Practice for Seismic Qualification of Class 1E Equipment for Nuclear Power Generating 

Stations,” (Ref. 4) and extended the application of that standard to the seismic qualification of mechanical 

equipment. In extending the application of IEEE Std 344-1987 to mechanical equipment, the NRC staff 

recognized differences in seismic qualification methods for electric equipment2

 (including instrumentation 

and control (I&C) components) and mechanical equipment. Specifically, Revision 2 of this regulatory 

guide stated that seismic qualification of mechanical equipment by analysis is permitted when such 

equipment can be modeled to adequately predict its response. Revision 2 also stated that the American 

Society of Mechanical Engineers (ASME) was developing a standard for seismic qualification of 

mechanical equipment and, upon publication of that standard the NRC staff would review it for suitability 

for endorsement by a revision of this regulatory guide. 

In 1994, the ASME issued a standard, ASME QME-1-1994, “Qualification of Active Mechanical 

Equipment Used in Nuclear Power Plants.” (Ref. 5) The ASME QME-1 covers both seismic qualification 

and functional qualification of active mechanical equipment. The ASME subsequently revised and 

reissued the standard in 1997, 2000, and 2002, with the last revision issued in November 2007 as ASME 

QME-1-2007 (Ref. 6). Furthermore, the IEEE updated IEEE Std 344-1987 and issued it as IEEE Std 344-

2004 (Ref. 7) in June 2005. 

The NRC developed this regulatory guide (i.e., Revision 3) to endorse, with exceptions and 

clarifications, the IEEE Std 344-2004 and the ASME QME-1-2007. (This is the first time the NRC is 

endorsing ASME QME-1). Specifically, Sections B.1 and C.1 of this regulatory guide endorse, with 

exceptions and clarifications, the entire IEEE Std 344-2004 and Section QR, “General Requirements,” and 

Nonmandatory Appendix QR-A, “Seismic Qualification of Active Mechanical Equipment,” of ASME 

QME-1-2007 for the seismic qualification of electric and active mechanical equipment, respectively. 

Sections B.2 and C.2 of this regulatory guide endorse, with exceptions and clarifications, Section QR and 

the remaining sections of ASME QME-1-2007 (except Nonmandatory Appendix QR-A) for the functional 

qualification of active mechanical equipment. The ASME QME-1 defines active mechanical equipment as 

“Mechanical equipment containing moving parts, which, in order to accomplish its required function as 

defined in Qualification Specification, must undergo or prevent mechanical movement. This includes any 

internal components or appurtenances whose failure degrades the required function of the equipment.” 

1. Seismic Qualification of Electric and Active Mechanical Equipment

The major change from IEEE Std 344-1987 to IEEE Std 344-2004 is the update and expansion of 

Clause 10, “Experience,” which describes the use of experience data as a method for seismic qualification 

of Class 1E electric equipment (including I&C components). Experience data include earthquake 

 

2

 Hereafter in this regulatory guide, the term “electric equipment” means an assembly of electric and electronic 

components designed and manufactured to perform specific functions, and the term “electric component” or 

“electronic component” means items from which the equipment is assembled (e.g., resistors, capacitors, wires, 

connectors, microprocessors, switches, springs, and instrumentation and control items). 
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experience data and test experience data. Nonmandatory Appendix QR-A to ASME QME-1-2007, which 

has been updated and expanded from Nonmandatory Appendix QR-A to ASME QME-1-2002, also 

includes the use of experience data as a method for seismic qualification of active mechanical equipment.

The use of earthquake experience data for seismic qualification of electric and mechanical 

equipment has its origin in the NRC research program associated with Unresolved Safety Issue (USI) A46, “Seismic Qualification of Mechanical and Electric Equipment in Operating Nuclear Power Plants.” In 

1980, the NRC staff raised a safety concern that licensees had not conducted the seismic qualification of 

electric and mechanical equipment in some older vintage NPPs (i.e., plants with construction permit 

applications docketed before about 1972) in accordance with the licensing criteria for seismic qualification 

of equipment acceptable at that time (i.e., IEEE Std 344-1975 (Ref. 8) and Regulatory Guide 1.100, 

Revision 1, (Ref. 9) issued August 1977). Therefore, equipment in the older vintage NPPs may not have 

been adequately qualified to ensure its structural integrity and/or proper functionality in the event of an 

SSE ground motion. As a result, the NRC established the USI A-46 program in December 1980 and, in 

February 1987, issued Generic Letter (GL) 87-02, “Verification of Seismic Adequacy of Mechanical and 

Electric Equipment in Operating Reactors, Unresolved Safety Issue (USI) A-46,” (Ref. 10) to address this 

safety concern. The NRC staff categorized approximately 70 NPP units in the United States as “USI A-46 

plants.” 

In 1982, the Seismic Qualification Utility Group (SQUG) undertook the development of an 

earthquake experience and a test experience database to address USI A-46. Because of the scarcity and 

low intensity level of earthquakes to which U.S. NPPs were exposed, the SQUG and its contractors 

performed a pilot study to determine the feasibility of using actual earthquake experience data from 

nonnuclear plants located worldwide (e.g., fossil-fueled power plants, substations, petrochemical plants) 

and existing test experience data from domestic NPPs to evaluate the performance of electric and 

mechanical equipment in those facilities to infer the susceptibility of similar NPP equipment to seismic 

loads. The SQUG concluded, and the NRC agreed, that the use of experience data was feasible for the 

purpose of verifying equipment seismic adequacy for the older vintage USI A-46 plants. 

Large uncertainties exist in the seismic qualification of equipment as a class on the basis of 

earthquake experience data because (1) it is difficult to compile a credible earthquake experience database 

(e.g., estimation of ground and floor earthquake excitations used in the earthquake experience database); 

(2) the inclusion rules and exclusion rules (termed “prohibited features” in IEEE Std 344-2004) of 

equipment in the database may not be complete; (3) the similarity between equipment in 

fossil/petrochemical plants in the database and those in NPPs is difficult to establish; and, most 

importantly, (4) generally there is no credible information from the earthquake experience database to 

provide assurance of the proper functionality of certain active electric equipment during earthquakes. 

Active electric equipment is the equipment that must either undergo a change of state or prevent a change 

of state in order to accomplish its required functions. The NRC staff is particularly concerned about the 

use of earthquake experience data for seismic qualification of active electric equipment that may 

inadvertently change state during an earthquake such that its intended safety functions are not performed 

during and/or after an earthquake. Examples of such active electric components are certain types of relays, 

contactors, circuit breakers, switches, sensors, and potentiometers. 

The NRC has three concerns regarding the use of test experience data for the seismic qualification 

of electric equipment. First, it is difficult to quantify the damage potential of equipment under testing 

since it depends on the combination of input motion and the equipment item exhibiting a particular 

malfunction. The resonant frequency corresponding to a given malfunction is mostly unknown, and this 

frequency for each item of equipment of the same class can differ significantly. There could be multiple 

malfunction mechanisms for components and subcomponents that need to be considered in comparing the 
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test response spectra (TRS) and the required response spectra (RRS). Therefore, an equipment capacity 

factor has to be considered to cover the uncertainties in high-level testing for an equipment class. Second, 

the technologies and designs of certain electric components (such as certain types of relays and 

microprocessor-based components) have undergone significant changes since the NRC issued Revision 2 

of this regulatory guide, as a result of the more prevalent use of digital I&C components in place of the 

traditional analog I&C components. Some solid-state relays and microprocessor-based components are 

quite fragile in terms of withstanding earthquake excitations. The staff considers the use of test experience 

data from the old-vintage electric components of this type for the seismic qualification of the new 

generation of such electric components to be inappropriate and unacceptable. Third, since no new NPPs 

were built after the early 1980s, a number of manufacturers for electric or active mechanical equipment are 

no longer in business, and the appropriateness of using the test experience of old equipment made by 

manufacturers no longer in business for the seismic qualification of modern equipment designs made by 

different manufacturers is highly questionable. 

The NRC staff has two other concerns as well. The NRC staff has a concern regarding electric 

and active mechanical equipment exposed to harsh environments, aging, and earthquakes. In such cases, 

the NRC staff does not find it acceptable to use experience data (earthquake or test experience data) for 

seismic qualification of equipment. The test sample shall be subjected to simulated operating-basis 

earthquake (OBE) and SSE seismic vibrations in accordance with IEEE Std 344-2004. 

 

Another NRC staff concern is the high-frequency earthquake ground motion for certain plant sites. 

Recent studies related to the early site permit applications at certain hard-rock-based plants along the east 

coast of the United States indicated that the site-specific spectra may exceed the certified design spectra of 

those new plants in the high-frequency range (20 hertz (Hz) and above). This exceedance cannot always 

be eliminated, even with incoherency added to the soil-structure interaction analyses. As a result of the 

high-frequency ground motion, the seismic input to SSCs may also contain high-frequency excitations. 

For operating boiling-water reactor (BWR) plants, the seismic qualifications of some safety-related electric 

and active mechanical equipment were performed using IEEE-344-type tests with intentional highfrequency contents to account for concurrent BWR hydrodynamic loads. However, the vast majority of 

existing seismic qualification tests used input frequencies up to only 33 Hz, although the TRS may have 

shown a zero period acceleration (ZPA) up to 100 Hz. Ball joints and kinematics linkages of the shake 

tables generated these inadvertent high frequencies, which the NRC staff considers to be noise signals that 

may not have the proper frequency content with sufficient energy to be compatible with the amplified 

region of the RRS at high frequencies. Therefore, any attempt to use such past test experience data for the 

seismic qualification of high-frequency-sensitive equipment or fragile components in such plants clearly is 

not appropriate. When new seismic qualification tests are planned for equipment in such plants, the 

formulation of the test input waveforms should properly consider this high-frequency ground motion 

concern. 

2. Functional Qualification of Active Mechanical Equipment 

The ASME QME-1-2007 describes requirements and guidelines for qualifying active mechanical 

equipment used in NPPs. The foreword to the standard indicates that the standard may be applied to future 

NPPs or existing operating NPP component replacements, modifications, or additions, as determined by 

regulators and the NPP licensees. The ASME QME-1-2007 provides functional qualification guidance for 

nonmetallic parts, dynamic restraints, pumps, and valves. The following sections and appendices of 

ASME QME-1-2007 provide the functional qualification guidance for this active mechanical equipment—

(1) Section QR, (2) Nonmandatory Appendix QR-B, “Guide for Qualification of Nonmetallic Parts,” (3) 

Section QDR, “Qualification of Dynamic Restraints,” and its Nonmandatory Appendices QDR-A, 

“Functional Specification for Dynamic Restraints,” QDR-B, “Restraint Similarity,” and QDR-C, “Typical 
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Values of Restraint Functional Parameters,” (4) Section QP, “Qualification of Active Pump Assemblies,” 

and its Nonmandatory Appendices QP-A, “Pump Specification Checklist,” QP-B, “Pump Shaft-Seal 

System Specification Checklist,” QP-C, “Pump Turbine Driver Specification Checklist,” QP-D, “Pump 

Similarity Checklist,” and QP-E, “Guidelines for Shaft-Seal System Material and Design Consideration,” 

and (5) Section QV, “Functional Qualification Requirements for Active Valve Assemblies for Nuclear 

Power Plants,” and its Mandatory Appendix QV-1, “Qualification Specification for Active Valves.” The 

major change from ASME QME-1-2002 to ASME QME-1-2007 in terms of the functional qualification of 

mechanical equipment is a complete rewrite of Section QV and the new Mandatory Appendix QV-1. 

 

In the 1980s and 1990s, operating experience at NPPs revealed a number of weaknesses in the 

initial design, qualification, testing, and performance of motor-operated valves (MOVs). For example, 

some engineering analyses used in the original sizing and setting of MOVs were found to predict 

inadequately the thrust and torque required to open and close valves under design-basis conditions. 

Similarly, some testing methods used to measure valve stroke times under zero differential-pressure and 

flow conditions were found not to detect deficiencies that could prevent MOVs from performing their 

safety functions under design-basis conditions. Both regulatory and industry research programs later 

confirmed weaknesses in the performance of MOVs. Such programs included extensive NRC research to 

study the performance of MOVs under various flow, temperature, and voltage conditions, and a nuclearindustry-sponsored program by the Electric Power Research Institute (EPRI) to develop a computer 

methodology to predict the performance of MOVs under a wide range of operating conditions. 

Responding to weaknesses found in the initial design, qualification, testing, and performance of 

MOVs, the NRC issued GL 89-10, “Safety-Related Motor-Operated Valve Testing and Surveillance,” 

(Ref. 11) in June 1989, which requested licensees to (1) ensure the capability of MOVs in safety-related 

systems to perform their intended functions by reviewing MOV design bases; (2) verify MOV switch 

settings initially and periodically; (3) test MOVs under design-basis conditions when practicable; (4) 

improve evaluations of MOV failures and necessary corrective action; and (5) trend MOV problems. The 

NRC staff evaluated various MOV NPP programs through onsite inspections of the design-basis capability 

of safety-related MOVs. 

In support of the regulatory activities to ensure MOV design-basis capability, the NRC conducted 

a research program to test several MOVs under normal flow and blowdown conditions. The NRC 

summarized the results of this MOV research program in Information Notice (IN) 90-40, “Results of NRCSponsored Testing of Motor-Operated Valves,” (Ref. 12) dated June 5, 1990. The testing revealed that 

(1) more thrust was required to operate gate valves than predicted by standard industry methods; (2) some 

valves were internally damaged under blowdown conditions and their operating requirements were 

unpredictable; (3) static and low-flow testing might not predict valve performance under design-basis flow 

conditions; (4) during valve opening strokes, the highest thrust requirements might occur at unseating or in 

the flow stream; (5) partial valve stroking did not reveal the total thrust required to operate the valve; (6) 

torque, thrust, and motor operating parameters were needed to fully characterize MOV performance; and 

(7) reliable use of MOV diagnostic data requires accurate equipment and trained personnel. 

To assist NPP licensees in responding to GL 89-10, the EPRI developed the MOV Performance 

Prediction Methodology (PPM) to determine dynamic thrust and torque requirements for gate, globe, and 

butterfly valves based on first principles of MOV design and operation. The EPRI described the 

methodology in Topical Report TR-103237, Revision 2, “EPRI MOV Performance Prediction Program,” 

(Ref. 13) issued in April 1997. The EPRI MOV PPM program included the development of improved 

methods for the prediction and evaluation of system flow parameters; gate, globe, and butterfly valve 

performance; and motor-actuator rate-of-loading effects (load-sensitive behavior). The EPRI conducted 

numerous valve tests to provide data for the development and validation of the valve performance models 
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and methods, including flow loop testing, parametric flow loop testing of butterfly valve disk designs, and 

in situ MOV testing. The NRC staff issued a safety evaluation (SE) in March 1996 (Ref. 14) accepting the 

EPRI MOV PPM with certain conditions and limitations. The NRC staff also issued supplements to the 

SE in February 1997 (Ref. 15), in April 2001 (Ref. 16), and in September 2002 (Ref. 17) to address 

updates to the EPRI MOV PPM. The NRC staff alerted licensees to lessons learned from the EPRI MOV 

program in IN 96-48, “Motor-Operated Valve Performance Issues,” (Ref. 18) dated August 21, 1996. 

In September 1996, the NRC issued GL 96-05, “Periodic Verification of Design-Basis Capability 

of Safety-Related Motor-Operated Valves,” (Ref. 19) to provide recommendations for ensuring the 

capability of safety-related MOVs to perform their design-basis functions over the long term. In response 

to GL 96-05, the NPP owners= groups developed an industrywide Joint Owners’ Group (JOG) program on 

MOV periodic verification to obtain benefits from sharing information among licensees on MOV 

performance. Following an interim MOV program and extensive dynamic MOV testing at NPPs, in 

February 2004, the JOG submitted to the NRC the Topical Report MPR-2524, Revision 0, “Joint Owners’ 

Group Motor Operated Valve Periodic Verification Program Summary,” (Ref. 20) providing long-term 

recommendations for the periodic verification of MOVs to be implemented by licensees as part of their 

commitments to GL 96-05. The NRC staff completed an SE on its evaluation of the JOG topical report in 

September 2006 (Ref. 21) 

In the late 1990s, the NRC conducted research to study the performance of alternating current (ac)-

powered MOV motor actuators manufactured by Limitorque Corporation under various temperature and 

voltage conditions. For the Limitorque ac-powered motor-actuator combinations tested, the research 

indicated that (1) actuator efficiency might not be maintained at the “run” efficiency published by the 

manufacturer; (2) degraded voltage effects can be more severe than predicted by the square of the ratio of 

actual to rated motor voltage; (3) some motors produce more torque output than predicted by their 

nameplate rating; and (4) temperature effects on motor performance appeared consistent with the 

Limitorque guidance. The NRC documented its study of ac-powered MOV output in NUREG/CR-6478, 

“Motor-Operated Valve (MOV) Actuator Motor and Gearbox Testing,” (Ref. 22) issued in July 1997. The 

nuclear industry also evaluated the output capability of ac-powered MOVs at several plants. In response to 

the new information on ac-powered MOV performance, Limitorque provided updated guidance in its 

Technical Update 98-01, “Actuator Output Torque Calculation,” (Ref. 23) issued in May 1998, and 

Supplement 1, issued in July 1998, for the prediction of ac-powered MOV motor actuator output. The 

NRC alerted licensees to the new information on ac-powered MOV output in Supplement 1 to IN 96-48 

(Ref. 24), dated July 24, 1998. 

Following the NRC review of ac-powered MOV performance, the NRC conducted research to 

study the performance of Limitorque direct current (dc)-powered MOV motor actuators under various 

temperature and voltage conditions. For the Limitorque dc-powered motor-actuator combinations tested, 

the research indicated that (1) the ambient temperature effects were more significant than predicted; (2) the 

use of a linear voltage factor needs to consider reduced speed, increased motor temperature, and reduced 

motor output; (3) the stroke-time increase is significant for some dc-powered MOVs under loaded 

conditions; and (4) the actuator efficiency may fall below the published “pullout” efficiency at low speed 

and high load conditions. The NRC documented this research in NUREG/CR-6620, “Testing of DCPowered Actuators for Motor-Operated Valves,” (Ref. 25) issued in May 1999. In June 2000, the Boiling 

Water Reactor Owners’ Group forwarded to the NRC the Topical Report NEDC-32958, “BWR Owners’ 

Group DC Motor Performance Methodology—Predicting Capability and Stroke Time in DC MotorOperated Valves,” (Ref. 26) issued in March 2000. In August 2001, the NRC issued Regulatory Issue 

Summary 2001-15, “Performance of DC-Powered Motor-Operated Valve Actuators,” (Ref. 27) to inform 

licensees of the availability of improved industry guidance for predicting dc-powered MOV actuator 

performance. 
DG-1175, Page 8 

Through an extensive effort spanning over many years, the ASME QME Standards Committee 

revised Section QV in ASME QME-1 to incorporate the lessons learned from the MOV operating 

experience and research programs for the functional qualification of all power-operated valves. The NRC 

staff participated in the activities of the ASME QME Standards Committee and its subcommittees during 

the revision of ASME QME-1. The staff presents its regulatory positions on ASME QME-1-2007 in 

Section C of this regulatory guide. 
DG-1175, Page 9 

C. REGULATORY POSITION

1. Seismic Qualification of Electric and Active Mechanical Equipment 

1.1 Regulatory Positions on IEEE Std 344-2004

1.1.1 General NRC Staff Positions

The IEEE Std 344-2004 is, in general, acceptable to the NRC staff for the seismic qualification of 

(1) electric equipment in new NPPs and (2) new addition or replacement electric equipment in operating 

NPPs, subject to the following provisions: 

a. Rigorous seismic qualification by analysis, testing, or combined analysis and testing, as described 

in Clauses 7, 8, and 9 of the IEEE Std 344-2004, are acceptable methods for seismic qualification 

of electric equipment. 

b. The use of experience data (earthquake or test experience data) for seismic qualification of electric 

equipment is subject to review by the NRC staff in areas such as (1) the credibility and 

completeness of the compilation of the experience database; (2) the inclusion rules and exclusion 

rules (termed “prohibited features” in IEEE Std 344-2004) for electric equipment in the experience 

database; (3) the justification used to demonstrate similarity among the member items in a 

reference equipment class and the similarity between electric equipment in the experience database 

and those in the NPP to be seismically qualified; (4) the justification used to demonstrate the 

reference equipment class functionality during and after the earthquake; and (5) the credibility of 

similarity among member items of a reference equipment class if a generic reference equipment 

class is proposed. As described in Clause 9.3 of IEEE Std 344-2004, similarity should include 

similarity in physical, functional, and dynamic characteristics between electric equipment in the 

experience database and those in the NPP to be seismically qualified, as well as similarity between 

seismic excitation noted in the experience database and the required seismic excitation for the 

electric equipment in the NPP to be seismically qualified. 

c. The NRC staff does not generally find it acceptable to use experience data (earthquake or test 

experience data) for seismic qualification for (1) certain active electric components that may 

inadvertently change state during an earthquake such that they do not consistently perform their 

intended safety functions during and/or after an earthquake, such as certain types of relays, 

contactors, circuit breakers, switches, sensors, and potentiometers; (2) fragile electronic 

components, such as solid-state relays and microprocessors-based components; and (3) electric 

equipment, such as battery chargers, inverters, relay and control panels, switchgear, and motor 

control centers. The electric equipment mentioned in (3) above generally consists of enclosures 

constructed of metal frames with metal panels that contain some of the components described in 

(1) and (2) above, and the response and performance of these components (and therefore the 

performance of the equipment) under earthquake loadings in general are sensitive to their locations 

and the type of mountings in such equipment. 

d. If the licensee proposes to use test experience data to perform seismic qualification, the licensee 

should submit for staff review and approval the details of the test experience database, including 

applicable implementation procedures, to assure the structural integrity and functionality of the inscope electric equipment. Supporting documentation for equipment identified in the database 

should confirm that such equipment will remain functional during and after the equivalent effect 

of five postulated occurrences of OBE and one SSE in combination with other relevant static and 

dynamic loads. 
DG-1175, Page 10 

e. For electric equipment exposed to harsh environments, aging, and earthquakes, the NRC staff does 

not find it acceptable to use experience data (earthquake or test experience data) for seismic 

qualification of equipment. The test sample shall be subjected to simulated OBE and SSE seismic 

vibrations in accordance with IEEE Std 344-2004. 

f. The NRC staff does not generally find it acceptable to restrict the frequency range of testing up to 

33 Hz. The frequency range should be continued beyond 33 Hz, in accordance with the RRS of a 

specific plant. 

g. For certain hard-rock-based plants, the site-specific spectra may exceed the certified design spectra 

in the high-frequency range. This guide refers to this phenomenon as the high-frequency ground 

motion concern. As a result of the high-frequency ground motion, the seismic input to SSCs may 

also contain high-frequency excitations. For operating BWR plants, the seismic qualifications of 

some safety-related electric equipment were performed using IEEE-344-type tests with intentional 

high-frequency contents to account for concurrent BWR hydrodynamic loads. However, the vast 

majority of existing seismic qualification tests used input frequencies up to only 33 Hz. These past 

test experience data are therefore not acceptable for the seismic qualification of high-frequencysensitive equipment or fragile components. Furthermore, credit should not be taken for the 

inadvertent high frequencies present in some of the IEEE-344-type seismic qualification tests of 

equipment in the past, which may have shown the ZPA of the TRS to be up to 100 Hz. Ball joints 

and kinematics linkages of the shake tables could have generated these inadvertent high 

frequencies, and the NRC staff considers them to be noise signals that may not have the proper 

frequency content with sufficient energy to be compatible with the amplified region of the RRS at 

high frequencies. 

h. If new seismic qualification tests are planned for equipment in plants with the high-frequency 

ground motion concern, the test input waveforms should be properly formulated to address this 

concern. In order for the TRS to be valid for such plants, the adequacy of the frequency content 

and the stationarity of the frequency content of the synthesized input waveforms used for the tests 

should be demonstrated. The frequency content of the Fourier transform of the test waveform or 

the frequency content of the power spectral density of the test waveform must be compatible with 

the amplified portion of the RRS. The Annex B, “Frequency Content and Stationarity,” to the 

IEEE 344-2004 provides guidelines on frequency content and stationarity. 

i. Electric equipment should be qualified with five one-half SSE events followed by one full SSE 

event (SECY-93-087) (Ref. 28) even if the OBE of a plant is defined to be one-third of SSE or 

less. Alternatively, a number of fractional peak cycles equivalent to the maximum peak cycle for 

five one-half SSE events may be used in accordance with Annex D, “Test Duration and Number 

of Cycles,” to IEEE Std 344-2004, when followed by one full SSE. 

j. The IEEE Std 344-2004 recommended no damping values. The damping values listed in Table 6 

of NRC Regulatory Guide 1.61, Revision 1, “Damping Values for Seismic Design of Nuclear 

Power Plants,” (Ref. 29) issued in March 2007, are recommended. These damping values are the 

updated values currently acceptable to the NRC staff. 

1.1.2 Specific NRC Staff Positions

The following are specific NRC staff positions, including exceptions and clarifications, on IEEE 

Std 344-2004: 

a. Clause 10.2.3.1 and Clause 10.3.3.1 (Experience—Attributes of Equipment Class) 

The NRC staff will review, in detail, the attributes of the equipment for establishing the inclusion 

rules that constitute the earthquake or test experience reference equipment class as described in 
DG-1175, Page 11 

Clause 10.2.3.1 or Clause 10.3.3.1, respectively, to determine the acceptability of similarity 

arguments to define a reference equipment class. 

To avoid addressing fatigue failure at low-cycle loads from earthquakes by simply considering it as 

a prohibited feature (Clause 10.2.3.1(b)) does not demonstrate successful equipment functionality 

under OBEs as required by the NRC regulations delineated in 10 CFR Part 100 (Ref. 30), 

Appendix S to 10 CFR Part 50, or 10 CFR Part 52. Earthquake experience data or test data are 

needed to demonstrate that all electric equipment in the reference equipment class, including the 

enclosed or attached devices or subassemblies, performed successfully (structural integrity and 

specified functionality) under the equivalent of five OBE and one SSE loadings. 

b. Clause 10.2.3.3 (Experience—Reference Equipment Class Functionality) 

Detailed information about the justification used to demonstrate the reference equipment class 

functionality during and after the earthquake should be submitted for NRC review and approval. 

c. Clause 10.2.4 (Earthquake Experience Data—Qualification of Candidate Equipment) 

The use of a median-centered horizontal in-structure response spectrum as the RRS for the 

candidate equipment is not acceptable. In-structure response spectra should be developed in 

accordance with the licensing basis and NRC guidance described in the latest revision of 

Regulatory Guide 1.122, “Development of Floor Design Response Spectra for Seismic Design of 

Floor-Supported Equipment or Components.” (Ref. 31) 

d. Clause 10.3.2 (Test Experience Data—Test Experience Spectra (TES)) 

i. The use of the frequency-by-frequency mean of the successful TRS is not adequate to 

define TES. When using test experience data, an equipment capacity factor has to be 

considered to obtain an equivalent confidence level for performance and to cover the 

uncertainties in high-level testing for an equipment class. The acceptable equipment 

capacity factor is 1.4 for TES (Refs. 32 and 33). 

Therefore, the NRC takes exception to the existing second sentence in the first paragraph 

of Clause 10.3.2. Instead, the following is acceptable to the NRC: 

The TES shall be the frequency-by-frequency mean divided by 1.4 of the 

response spectra from successful tests without malfunction. 

ii. The second paragraph of Clause 10.3.2 is not appropriate. The position acceptable to the 

NRC staff is the one stated in Section C.1.1.1.i of this regulatory guide. 

e. Clause 10.3.3 (Test Experience Data—Characterization of Reference Equipment Class) 

Clause 10.3.3 cites an example that significant natural frequencies of the reference equipment 

class would lie within approximately one-third octave. This will not provide an adequate range of 

significant natural frequencies of the reference equipment in a class. Instead of one-third octave, 

one-sixth octave should be used. 

f. Clause 10.3.3.2 (Test Experience Data—Number of Independent Items for Reference Equipment 

Class) 
DG-1175, Page 12 

Justification should be provided to show the adequacy of using a minimum of five independent 

items to define a reference equipment class for test experience. 

g. Clause 10.3.4 (Test Experience Data—Qualification of Candidate Equipment) 

The use of a median-centered horizontal in-structure response spectrum as the RRS for the 

candidate equipment is not acceptable. In-structure response spectra should be developed in 

accordance with the licensing basis and NRC guidance described in the latest revision of 

Regulatory Guide 1.122. 

h. Clause 10.4.2 (Experience—Limitations) 

The list of limitations for the use of earthquake- or test-experience-based methods for seismic 

qualification of equipment as described in Clause 10.4.2 may not be complete. The list should be 

expanded to include additional limitations as a result of new findings from testing new equipment 

or new studies. 

i Annex C (Fragility Testing) 

 

An example of determining the fragility level to single-frequency transient excitation of the 

equipment is to subject it to any single-frequency excitation such as sine-beat motion. The 

frequency range of the test excitation should be continued beyond 33 Hz, in accordance with the 

RRS of a specific plant. 

j. Annex D (Test Duration and Number of Cycles) 

 

Figure D.2 is used to determine the equivalent number of fatigue cycles for a given filtered 

frequency and duration. Currently, IEEE Std 344-2004 does not develop guidance beyond 40 Hz. 

Therefore, justification should be provided for applications beyond 40 Hz. 

k. Annex E (Statistically Independent Motions) 

A coherence function of less than 0.5 and an absolute value of the correlation coefficient function 

of less than 0.3 are not acceptable. 

The NRC positions on the numerical values for the coherence function and the correlation 

coefficient function for defining statistically independent motions are the same as in Reference 34, 

particularly the following: 

i. For the coherence function, numerical values ranging from 0.0 to a maximum of 0.3 and 

an average of approximately 0.2 are acceptable. 

ii. An absolute value of less than 0.16 for the correlation coefficient function is acceptable. 

1.2 Regulatory Positions on ASME QME-1-2007

1.2.1 General NRC Staff Positions 

 In the discussion of the seismic qualification of some active mechanical equipment, ASME QME1-2007 references IEEE Std-344-1987 (as addressed in NRC Regulatory Guide 1.100, Revision 2) or 
DG-1175, Page 13 

Nonmandatory Appendix QR-A. Such references appear in several sections of ASME QME-1-2007, 

such as Section QP-6400 for pumps, and Sections QV-7450 and QV-7650 for valves. The NRC staff 

finds these acceptable if they are applied consistent with the NRC staff positions delineated in this 

regulatory guide (Revision 3) and other relevant NRC regulatory documents. 

The NRC staff finds Nonmandatory Appendix QR-A to ASME QME-1-2007 acceptable, in 

general, for seismic qualification of (1) active mechanical equipment in new NPPs; and (2) new addition or 

replacement active mechanical equipment in operating NPPs. However, the NRC staff acknowledges the 

statement in Section QR-A7500 that the section on test-experience-based qualification is currently not 

available in ASME QME-1-2007 and will be added in a later issue of the standard. In addition, the NRC 

has the following regulatory positions, including exceptions and clarifications, on Nonmandatory 

Appendix QR-A of ASME QME-1-2007: 

a. In endorsing the use of ASME QME-1-2007, the staff noticed that several appendices are 

designated as either nonmandatory or mandatory (e.g., Nonmandatory Appendix QR-A; 

Nonmandatory Appendix QR-B; Nonmandatory Appendices QDR-A, QDR-B, and QDR-C; 

Nonmandatory Appendices QP-A, QP-B, QP-C, QP-D, and QP-E; and Mandatory 

Appendix QV-1). The staff position is that, once the user commits to the use of ASME QME-1-

2007 for its qualification of active mechanical equipment in NPPs, the criteria and procedures 

delineated in those appendices then become the requirements for its qualification program, unless 

the deviations are justified. 

b. Rigorous seismic qualification by analysis or testing, as described in Sections QR-A7100 and QRA7200 of ASME QME-1-2007, is an acceptable method for seismic qualification of active 

mechanical equipment. 

c. The ASME Class 1, 2, and 3 active mechanical equipment should meet the requirements in the 

ASME Boiler and Pressure Vessel Code (hereafter referred to as the ASME Code), Section III 

(Ref. 35). The NRC staff recommends that a future revision of ASME QME-1 add this position to 

(1) Section QR-6000, “Qualification Specification,” as item (j); and (2) Section QR-A7440, 

“Qualification of Candidate Equipment,” as item (g).

d. The NRC staff will review the use of earthquake experience data for seismic qualification of active 

mechanical equipment in areas such as (1) the credibility and completeness of the compilation of 

the experience database; (2) the inclusion rules and exclusion rules for active mechanical 

equipment in the experience database; (3) the justification used to demonstrate similarity among 

the member items in a reference equipment class and the similarity between active mechanical 

equipment in the experience database and those in the NPP to be seismically qualified; (4) the 

justification used to demonstrate the functionality of candidate equipment during and after the 

earthquake; and (5) the credibility of similarity among member items of a reference equipment 

class if a generic reference equipment class is proposed. As described in Section QR-A7300 of 

ASME QME-1-2007, similarity should include similarity in physical, functional, and dynamic 

characteristics between mechanical equipment in the experience database and those in the NPP to 

be seismically qualified, as well as similarity between seismic excitation documented in the 

experience database and the required seismic excitation for the mechanical equipment in the NPP 

to be seismically qualified. 

e. If the licensee proposes to use test experience for seismic qualification, the licensee should submit 

for staff review and approval the details of the test experience database, including applicable 

implementation procedures, to assure the structural integrity and functionality of the in-scope 

mechanical equipment. Supporting documentation for equipment identified in the database should 

confirm that such equipment will remain functional during and after the equivalent effect of five 

postulated occurrences of an OBE and one SSE in combination with other relevant static and 

dynamic loads. 
DG-1175, Page 14 

f. The NRC staff does not generally find it acceptable to restrict the frequency range of testing up to 

33 Hz. The frequency range should be continued beyond 33 Hz, in accordance with the RRS of a 

specific plant. 

g. For certain hard-rock-based plants, the site-specific spectra may exceed the certified design spectra 

in the high-frequency range. This guide refers to this phenomenon as the high-frequency ground 

motion concern. As a result of the high-frequency ground motion, the seismic input to SSCs may 

also contain high-frequency excitations. For operating BWR plants, the seismic qualification of 

some safety-related active mechanical equipment were performed using IEEE-344-type tests with 

intentional high-frequency contents to account for concurrent BWR hydrodynamic loads. 

However, the vast majority of existing seismic qualification tests used input frequencies up to only 

33 Hz. These past test experience data are therefore not acceptable for the seismic qualification of 

high-frequency-sensitive equipment or fragile components. Furthermore, credit should not be 

taken for the inadvertent high frequencies present in some of the IEEE-344-type seismic 

qualification tests of equipment in the past, which may have shown the ZPA of the TRS to be up 

to 100 Hz. Ball joints and kinematics linkages of the shake tables could have generated these 

inadvertent high frequencies, and the NRC staff considers them to be noise signals that may not 

have the proper frequency content with sufficient energy to be compatible with the amplified 

region of the RRS at high frequencies. 

h. If new seismic qualification tests are planned for active mechanical equipment in plants with the 

high-frequency ground motion concern, the test input waveforms should be properly formulated to 

address this concern. For the TRS to be valid for such plants, the adequacy of the frequency 

content and the stationarity of the frequency content of the synthesized input waveforms used for 

the tests should be demonstrated. The frequency content of the Fourier transform of the test 

waveform or the frequency content of the power spectral density of the test waveform should be 

compatible with the amplified portion of the RRS. The Annex B to IEEE 344-2004 provides 

guidelines on frequency content and stationarity. 

i. For active mechanical equipment exposed to harsh environments, aging, and earthquakes, the staff 

does not find it acceptable to use experience data (earthquake or test experience data) for seismic 

qualification of equipment. The test sample shall be subjected to simulated OBE and SSE seismic 

vibrations in accordance with IEEE Std 344-2004. 

j. Active mechanical equipment should be qualified with five one-half SSE events followed by one 

full SSE event (SECY-93-087) even if the OBE of a plant is defined to be one-third of SSE or 

less. Alternatively, a number of fractional peak cycles equivalent to the maximum peak cycle for 

five one-half SSE events may be used in accordance with Annex D to IEEE Std 344-2004 when 

followed by one full SSE. 

1.2.2 Specific NRC Staff Positions

The following are specific NRC staff positions, including exceptions and clarifications, on ASME 

QME-1-2007: 

a. Section QR-A6200 (Damping) 

Instead of the damping values listed in Table QR-A6210-1, the damping values listed in Tables 1 

to 6 of NRC Regulatory Guide 1.61, Revision 1, are recommended. These damping values are the 

updated values currently acceptable to the NRC staff. 

b. Section QR-A6300 (Seismic Qualification Requirements—Required Response Spectrum) 
DG-1175, Page 15 

The Section QR-A6300 states that “For in-line active mechanical equipment qualified in 

accordance with QR-A7400 (Earthquake Experience-Based Qualification), the RRS is typically 

the building filtered response spectrum at the distribution system support attachments to the 

building.” The use of the building filtered response spectrum at the distribution system support 

attachments to the building as the RRS for the in-line equipment may not be adequate. The RRS 

for in-line active mechanical equipment should account for the potential motion amplification of 

the distribution system. 

c. Section QR-A7331 (Qualification by Similarity—Excitation) 

The Section QR-A7331 states that “a conservative composite excitation may be generated by 

extrapolations or interpolations of data whose parameters are not identical but are justifiable. 

Likewise, excitation whose spectral content are significantly different may be used to generate 

lower-level composite estimates, providing that an account is taken of possible multi-axis response 

or cross-axis coupling, or both.” The licensee should provide detailed information, justifying this 

statement, to the NRC staff for review and approval. 

d. Section QR-A7421 (Earthquake Experience-Based Qualification—Attributes of Equipment Class) 

The NRC staff will review, in detail, the attributes of the equipment for establishing the inclusion 

rules that constitute the earthquake experience reference equipment class as described in 

Section QR-A7421 to determine the acceptability of similarity arguments to define a reference 

equipment class. 

Section QR-A7421 also states the following: 

“Prohibited features should include any attributes that would contribute to fatigue 

failure from low cycle loads. The rules of this section apply to active mechanical 

equipment that may undergo 5 OBE’s or aftershocks and one SSE resulting in 

60 full range stress cycles during plant life. If a component contains items which 

could experience a fatigue failure from low cycle loads (less than 60 full range 

stress cycles), it shall be evaluated in accordance with Section QR-A6800.” 

The NRC regulations delineated in 10 CFR Part 100, Appendix S to 10 CFR Part 50, and 

10 CFR Part 52 require the demonstration of successful equipment functionality under OBEs. 

e. Section QR-A7423 (Functionality during Earthquake) 

Detailed information about the justification used to demonstrate the reference equipment class 

functionality during and after the earthquake should be submitted for NRC review and approval. 

f. Section QR-A7431 (Earthquake Experience-Based Qualification—Inherently Rugged Active 

Mechanical Equipment) 

To justify the active mechanical equipment class as an “inherently rugged active mechanical 

equipment” class, the licensee should provide, for NRC review, information regarding the 

operational or shipping loads as compared to the expected seismic loads that the equipment could 

be subjected to, and the explicit design standards applied to this equipment class. Detailed 

information regarding the simplified and reduced rules, including the technical justification and 

data for characterizing the inherently rugged active mechanical equipment class and the procedure 
DG-1175, Page 16 

for defining the seismic capacity for this equipment class (i.e., the earthquake experience 

spectrum), should also be provided to the NRC staff for review.

g. Section QR-A7432 (Earthquake Experience-Based Qualification—Limitations) 

The limitations for the use of an earthquake-experience-based method of seismic qualification of 

equipment, as described in Section QR-A7432, may not be a complete list. The list should be 

expanded to include additional limitations as a result of new findings from testing of new 

equipment or new studies. 

h. Section QR-A7440 (Earthquake Experience-Based Qualification—Qualification of Candidate 

Equipment) 

The use of a median-centered horizontal in-structure response spectrum as the RRS for the 

candidate equipment is not acceptable. In-structure response spectra should be developed in 

accordance with the licensing basis and NRC guidance described in the latest revision of 

Regulatory Guide 1.122. 

i. Section QR-A8330 (Qualification Report—Earthquake Experience-Based Qualification 

Documentation) 

All ASME Class 1, 2, and 3 active mechanical equipment should comply with the ASME Code, 

Section III, requirements. The NRC staff recommends adding the following item to a future 

revision of ASME QME-1: 

(f) compliance with the ASME Code, Section III, requirements for ASME 

Class 1, 2, and 3 active mechanical equipment. 

j. Attachment C to Nonmandatory Appendix QR-A (Qualification of Pumps and Valves Using 

Natural Earthquake Experience Data) 

Attachment C to Nonmandatory Appendix QR-A is based on the guidelines developed by the 

SQUG for USI A-46 plants. The provisions in the SQUG guidelines rely heavily on earthquake 

experience data that the staff considered reasonable for verification of existing equipment seismic 

adequacy, and the qualification of new and replacement equipment in older vintage USI A-46 

plants only. The NRC staff has not accepted these SQUG guidelines for the seismic qualification 

of equipment in plants other than USI A-46 plants. The provisions outlined in Section QR-A7400, 

including the NRC staff’s positions noted in Sections C.1.2.1 and C.1.2.2 of this regulatory guide, 

are acceptable for the seismic qualification of active mechanical components. In addition, contrary 

to the provisions in Section QR-A7400, the introduction to Attachment C states that the data have 

not been developed to conclusively demonstrate that pumps and valves function properly during 

earthquakes. Therefore, Attachment C in its current form does not fully comply with the 

requirements in 10 CFR Part 100. Attachment C also contains an error in Section C-2. The 

equipment frequency restriction should be greater than 8 Hz instead of less than 8 Hz. 
DG-1175, Page 17 

2. Functional Qualification of Active Mechanical Equipment 

2.1 Regulatory Positions on ASME QME-1-2007

2.1.1 General NRC Staff Positions

 In general, the NRC staff finds ASME QME-1-2007 acceptable for the functional qualification of 

(1) active mechanical equipment in new NPPs; and (2) new addition or replacement of active mechanical 

equipment in operating NPPs, subject to the following provisions: 

a. Appendices 

In endorsing the use of ASME QME-1-2007, the staff acknowledged that several appendices are 

designated as either nonmandatory or mandatory (e.g., Nonmandatory Appendix QR-A; 

Nonmandatory Appendix QR-B; Nonmandatory Appendices QDR-A, QDR-B, and QDR-C; 

Nonmandatory Appendices QP-A, QP-B, QP-C, QP-D, and QP-E; and Mandatory 

Appendix QV-1). The NRC staff’s position is that, once the user commits to the use of ASME 

QME-1-2007 for its qualification of active mechanical equipment in NPPs, the criteria and 

procedures delineated in those appendices then become mandatory and are the requirements for its 

qualification program. Justification must be provided for any deviations, which will be subjected 

to NRC staff review and approval. 

b. Nonmandatory Appendix QR-B 

This appendix recommends a methodology and describes the documentation that should be 

available in a user’s files to demonstrate the qualification of nonmetallic parts, materials, or 

lubricants. It addresses the steps for the user of the active mechanical equipment to follow to 

qualify and maintain qualification of the nonmetallic material that is part of the active mechanical 

equipment. The NRC staff considers Nonmandatory Appendix QR-B to provide a reasonable 

approach to the qualification of nonmetallic material in active mechanical equipment. 

c. Sections QDR and QP 

The NRC staff considers Sections QDR and QP to provide a reasonable approach to the 

qualification of dynamic restraints and active pump assemblies, respectively. These sections have 

not changed from those in ASME QME-1-2002, and they still adequately document the state of 

the art of the nuclear industry in the qualification of dynamic restraints and active pump 

assemblies. 

d. Section QV 

The revision to ASME QME-1 reflects valve performance information obtained from nuclear 

industry programs and NRC’s research since the development of ASME QME-1 in the 1980s. 

With the active involvement of industry personnel and the NRC staff in the development of ASME 

QME-1-2007, only a few NRC staff exceptions and clarifications are necessary in this guide for 

Section QV, as described in Section C.2.1.2 of this regulatory guide below. 
DG-1175, Page 18 

2.1.2 Specific NRC Staff Positions

a. The definition of “valve assembly” in Section QV-4000, “Definitions,” refers to power-operated 

valves. The NRC staff considers the power actuators for valve assemblies to include all types of 

power actuators, such as motor, pneumatic, hydraulic, solenoid, and other drivers. 

b. The Section QV-6000, “Qualification Specification,” states that the owner or owner’s designee is 

responsible for identifying the functional requirements for a valve assembly, and that these 

requirements shall be provided in a qualification specification prepared in accordance with 

Mandatory Appendix QV-1. The NRC staff considers Mandatory Appendix QV-1 to be a 

necessary part of the implementation of Section QV of ASME QME-1-2007. For example, 

Mandatory Appendix QV-1 provides the definitions of QV Category A and B valve assemblies 

used in Section QV of ASME QME-1-2007. 
DG-1175, Page 19 

D. IMPLEMENTATION 

The purpose of this section is to provide information to applicants and licensees regarding the 

NRC’s plans for using this draft regulatory guide. No imposition or backfit is intended or approved in 

connection with its issuance. 

The NRC has issued this draft guide to encourage public participation in its development. The 

NRC will consider all public comments received in development of the final guidance document. Except 

in those cases in which an applicant or licensee proposes or has previously established an acceptable 

alternative method for complying with specified portions of the NRC’s regulations, the methods described 

in the active guide will be used in evaluating compliance with the regulations as discussed in this guide for 

license applications, license amendment applications, and exemption requests. 

REGULATORY ANALYSIS

1. Statement of the Problem 

The NRC issued Revision 2 of Regulatory Guide 1.100 in June 1988 to endorse (with exceptions 

and clarifications) IEEE Std 344-1987 and to describe acceptable methods for complying with the NRC’s 

regulations governing the seismic qualification of NPP electric (including I&C components) and active 

mechanical equipment that is important to safety. Since the issuance of Revision 2 of Regulatory 

Guide 1.100 in 1988, two consensus standards, IEEE Std 344-2004 and ASME QME-1-2007, have been 

revised and issued in 2005 and 2007, respectively. With some exceptions and clarifications, this 

regulatory guide (Revision 3) endorses these two consensus standards and describes methods that the NRC 

staff considers acceptable in the areas of seismic qualification of electric and active mechanical equipment 

and functional qualification of active mechanical equipment. 

2. Objective

The objective of the regulatory action is to update the NRC’s guidance in the area of seismic 

qualification of electric and active mechanical equipment and functional qualification of active mechanical 

equipment. 

3. Alternatives Approaches 

The NRC staff considered the following alterative approaches: 

• Do not revise Regulatory Guide 1.100. 

• Update Regulatory Guide 1.100. 
DG-1175, Page 20 

3.1 Alternative 1: Do Not Revise Regulatory Guide 1.100

Under this alternative, the NRC would not revise Regulatory Guide 1.100 and licensees would 

continue to rely on the current version (Revision 2), which is based on technology developed in the 1980s. 

Since then several newer developments that have improved the engineering understanding have been 

incorporated in updated standards. This alternative is considered the baseline or “no-action” alternative. 

3.2 Alternative 2: Update Regulatory Guide 1.100

Under this alternative, the NRC would update Regulatory Guide 1.100 to reference the two latest 

consensus standards (see above) and to describe the NRC’s positions on these two consensus standards. 

The staff has identified the following potential benefits associated with adopting alternative 2: 

• Licensees would have NRC guidance on the use of the latest IEEE and ASME consensus 

standards related to the seismic qualification of electric and active mechanical equipment and 

functional qualification of active mechanical equipment. 

• Regulatory efficiency would be improved by reducing uncertainty on acceptable methods to follow 

and by encouraging consistency in the seismic qualification of electric and active mechanical 

equipment and the functional qualification of active mechanical equipment. The NRC reviews 

would be facilitated because licensee submittals would be more predictable and consistent. 

• Both the NRC and the nuclear industry would realize cost savings. From the NRC’s perspective, 

relative to the baseline, the agency will incur one-time minimal incremental cost to issue the 

revised regulatory guide. However, the NRC should also realize cost savings associated with the 

review of licensee submittals; the ongoing cost savings associated with these reviews should more 

than offset the one-time cost. 

• The updated regulatory guide will clarify for the industry the NRC positions on the two standards. 

The NRC staff expects that industry will realize a net savings by the efficiencies (e.g., fewer 

follow-up questions and revisions) associated with each licensee submission. 

4. Conclusion

Based on this regulatory analysis, the staff recommends that the NRC revise Regulatory 

Guide 1.100. The staff concludes that the proposed action will clarify the NRC positions on the two 

standards related to seismic qualification of electric and active mechanical equipment and functional 

qualification of active mechanical equipment. The staff also concludes that no adverse effects are 

associated with revising Regulatory Guide 1.100. 

 
DG-1175, Page 21 

REFERENCES

1. 10 CFR Part 50, “Domestic Licensing of Production and Utilization Facilities,” U.S. Nuclear 

Regulatory Commission, Washington, DC.3

2. 10 CFR Part 52, “Early Site Permits; Standard Design Certifications; and Combined Licenses for 

Nuclear Power Plants,” U.S. Nuclear Regulatory Commission, Washington, DC. 

3. Regulatory Guide 1.100, Revision 2, “Seismic Qualification of Electric and Mechanical 

Equipment for Nuclear Power Plants,” U.S. Nuclear Regulatory Commission, Washington, DC, 

June 1988.4

4. IEEE Std 344-1987, “IEEE Recommended Practice for Seismic Qualification of Class 1E 

Equipment for Nuclear Power Generating Stations,” Institute of Electrical and Electronics 

Engineers, Inc., New York, NY, January 1987.5

5. ASME QME-1-1994, “Qualification of Active Mechanical Equipment Used in Nuclear Power 

Plants,” American Society of Mechanical Engineers, New York, NY, June 1994.6

 

6. ASME QME-1-2007, “Qualification of Active Mechanical Equipment Used in Nuclear Power 

Plants,” American Society of Mechanical Engineers, New York, NY, November 2007. 

7. IEEE Std 344-2004, “IEEE Recommended Practice for Seismic Qualification of Class 1E 

Equipment for Nuclear Power Generating Stations,” Institute of Electrical and Electronics 

Engineers, Inc., New York, NY, June 2005. 

 

3

 All NRC regulations listed herein are available electronically through the Electronic Reading Room on the NRC’s 

public Web site, at http://www.nrc.gov/reading-rm/doc-collections/cfr/. Copies are also available for inspection or 

copying for a fee from the NRC’s Public Document Room (PDR) at 11555 Rockville Pike, Rockville, MD; the mailing 

address is USNRC PDR, Washington, DC 20555; telephone (301) 415-4737 or (800) 397-4209; fax (301) 415-3548; 

and e-mail PDR@nrc.gov. 

4

 All regulatory guides listed herein were published by the U.S. Nuclear Regulatory Commission. Most are available 

electronically through the Electronic Reading Room on the NRC’s public Web site, at http://www.nrc.gov/ 

reading-rm/doc-collections/reg-guides/. Active guides may also be purchased from the National Technical Information 

Service (NTIS) on a standing order basis. Details on this service may be obtained by contacting NTIS at 5285 Port 

Royal Road, Springfield, VA 22161, online at http://www.ntis.gov, by telephone at (800) 553-NTIS (6847) or (703) 

605-6000, or by fax at (703) 605-6900. Copies are also available for inspection or copying for a fee from the NRC’s 

Public Document Room (PDR) at 11555 Rockville Pike, Rockville, MD; the mailing address is USNRC PDR, 

Washington, DC 20555-0001; telephone (301) 415-4737 or (800) 397-4209; fax (301) 415-3548, and e-mail 

PDR@nrc.gov. 

5 Copies of Institute of Electrical and Electronics Engineers (IEEE) standards may be purchased from IEEE Service 

Center, 445 Hoes Lane, Piscataway, NJ 08854; telephone (800) 678-4333. Purchase information is available through 

the IEEE Web-based store at http://www.ieee.org. 

6

 Copies of American Society of Mechanical Engineers (ASME) standards may be purchased from ASME, Three Park 

Avenue, New York, NY 10016-5990; telephone (800) 843-2763. Purchase information is available through the ASME 

Web-based store at http://www.asme.org/Codes/Publications/. 
DG-1175, Page 22 

8. IEEE Std 344-1975, “IEEE Recommended Practice for Seismic Qualification of Class 1E 

Equipment for Nuclear Power Generating Stations,” Institute of Electrical and Electronics 

Engineers, Inc., New York, NY, 1975. 

9. Regulatory Guide 1.100, Revision 1, “Seismic Qualification of Electric and Mechanical 

Equipment for Nuclear Power Plants,” U.S. Nuclear Regulatory Commission, Washington, DC, 

August 1977. 

10. Generic Letter 87-02, “Verification of Seismic Adequacy of Mechanical and Electric Equipment 

in Operating Reactors, Unresolved Safety Issue (USI) A-46,” U.S. Nuclear Regulatory 

Commission, Washington, DC, February 1987.7

11. Generic Letter 89-10, “Safety-Related Motor-Operated Valve Testing and Surveillance,” 

U.S. Nuclear Regulatory Commission, Washington, DC, June 1989. 

12. Information Notice 90-40, “Result of NRC-Sponsored Testing of Motor-Operated Valves,” 

U.S. Nuclear Regulatory Commission, Washington, DC, June 1990.8

13. Topical Report TR-103237, Revision 2, “EPRI MOV Performance Prediction Program,” and 

Addenda 1 and 2, nonproprietary versions, Electric Power Research Institute, Palo Alto, CA, April 

1997.9

14. Safety Evaluation, “Safety Evaluation on EPRI MOV Performance Prediction Methodology,” U.S. 

Nuclear Regulatory Commission, Washington, DC, March 1996. 

15. Safety Evaluation Supplement, “Supplement to Safety Evaluation on EPRI MOV Performance 

Prediction Methodology,” U.S. Nuclear Regulatory Commission, Washington, DC, February 

1997. 

16. Safety Evaluation Supplement, “Supplement 2 to Safety Evaluation on EPRI MOV Performance 

Prediction Methodology,” U.S. Nuclear Regulatory Commission, Washington, DC, April 2001. 

17. Safety Evaluation Supplement, “Supplement 3 to Safety Evaluation on EPRI MOV Performance 

Prediction Methodology,” U.S. Nuclear Regulatory Commission, Washington, DC, September 

2002. 

 

7 All generic letters (GLs) listed herein were published by the U.S. Nuclear Regulatory Commission and are available 

electronically through the Electronic Reading Room on the NRC’s public Web site, at http://www.nrc.gov/ 

reading-rm/doc-collections/gen-comm/gen-letters/. Copies are also available for inspection or copying for a fee from 

the NRC’s Public Document Room at 11555 Rockville Pike, Rockville, MD; the mailing address is USNRC PDR, 

Washington, DC 20555-0001; telephone (301) 415-4737 or (800) 397-4209; fax (301) 415-3548; and 

e-mail PDR@nrc.gov. 

8 All information notices (INs) listed herein were published by the U.S. Nuclear Regulatory Commission and are 

available electronically through the Electronic Reading Room on the NRC’s public Web site, at 

http://www.nrc.gov/reading-rm/doc-collections/gen-comm/info-notices/. Copies are also available for inspection or 

copying for a fee from the NRC’s Public Document Room at 11555 Rockville Pike, Rockville, MD; the mailing 

address is USNRC PDR, Washington, DC 20555; telephone (301) 415-4737 or (800) 397-4209; fax (301) 415-3548; 

and e-mail PDR@nrc.gov

9 Copies of the listed Electric Power Research Institute (EPRI) standards and reports may be purchased from EPRI, 

3420 Hillview Ave., Palo Alto, CA 94304; telephone (800) 313-3774; fax (925) 609-1310. 
DG-1175, Page 23 

18. Information Notice 96-48, “Motor-Operated Valve Performance Issues,” U.S. Nuclear Regulatory 

Commission, Washington, DC, August 1996. 

19. Generic Letter 96-05, “Periodic Verification of Design-Basis Capability of Safety-Related MotorOperated Valves,” U.S. Nuclear Regulatory Commission, Washington, DC, September 1996. 

20. Topical Report MPR-2524, “Joint Owners’ Group Motor Operated Valve Periodic Verification 

Program Summary,” Joint Owners’ Group, February 2004. 

21. Final Safety Evaluation, “Final Safety Evaluation on Joint Owners’ Group Program on MotorOperated Valve Periodic Verification,” U.S. Nuclear Regulatory Commission, Washington, DC, 

September 2006. 

22. NUREG/CR-6478, “Motor-Operated Valve (MOV) Actuator Motor and Gearbox Testing,” 

U.S. Nuclear Regulatory Commission, Washington, DC, July 1997.10

23. Technical Update 98-01, “Actuator Output Torque Calculation,” Limitorque Corporation, 

Lynchburg, VA, May 1998, and Supplement 1, July 1998. 

24. Information Notice 96-48, Supplement 1, “Motor-Operated Valve Performance Issues,” U.S. 

Nuclear Regulatory Commission, Washington, DC, July, 1998. 

25. NUREG/CR-6620, “Testing of DC-Powered Actuators for Motor-Operated Valves,” 

U.S. Nuclear Regulatory Commission, Washington, DC, May 1999. 

26. Topical Report NEDC-32958, “BWR Owners’ Group DC Motor Performance Methodology—

Predicting Capability and Stroke Time in DC Motor-Operated Valves,” Boiling Water Reactor 

Owners’ Group, March 2000. 

27. Regulatory Issue Summary 2001-15, “Performance of DC-Powered Motor-Operated Valve 

Actuators,” U.S. Nuclear Regulatory Commission, Washington, DC, August 2001.11

28. SECY-93-087, “Policy, Technical, and Licensing Issues Pertaining to Evolutionary and Advanced 

Light-Water Reactor (ALWR) Designs,” ADAMS ML No: ML003708021, U.S. Nuclear 

 

10 All NUREG-series reports listed herein were published by the U.S. Nuclear Regulatory Commission. Most are 

available electronically through the Electronic Reading Room on the NRC’s public Web site, at http://www.nrc.gov/ 

reading-rm/doc-collections/nuregs/. Copies are also available for inspection or copying for a fee from the NRC’s 

Public Document Room (PDR) at 11555 Rockville Pike, Rockville, MD; the mailing address is USNRC PDR, 

Washington, DC 20555; telephone (301) 415-4737 or (800) 397-4209; fax (301) 415-3548; and e-mail PDR@nrc.gov. 

 In addition, copies are available at current rates from the U.S. Government Printing Office, P.O. Box 37082, 

Washington, DC 20402-9328, telephone (202) 512-1800, or from the National Technical Information Service (NTIS), 

at 5285 Port Royal Road, Springfield, VA 22161, online at http://www.ntis.gov, by telephone at (800) 553-NTIS 

(6847) or (703) 605-6000, or by fax at (703) 605-6900. 

11 All regulatory issue summaries (RISs) listed herein were published by the U.S. Nuclear Regulatory Commission and 

are available electronically through the Electronic Reading Room on the NRC’s public Web site, 

at http://www.nrc.gov/reading-rm/doc-collections/gen-comm/reg-issues/. Copies are also available for inspection or 

copying for a fee from the NRC’s Public Document Room at 11555 Rockville Pike, Rockville, MD; the mailing 

address is USNRC PDR, Washington, DC 20555; telephone (301) 415-4737 or (800) 397-4209; fax (301) 415-3548; 

and e-mail PDR@nrc.gov. 
DG-1175, Page 24 

Regulatory Commission, Washington, DC, April 1993. 

29. Regulatory Guide 1.61, Revision 1, “Damping Values for Seismic Design of Nuclear Power 

Plants,” U.S. Nuclear Regulatory Commission, Washington, DC, March 2007. 

30. 10 CFR Part 100, “Reactor Site Criteria,” U.S. Nuclear Regulatory Commission, Washington, DC. 

31. Regulatory Guide 1.122, “Development of Floor Design Response Spectra for Seismic Design of 

Floor-Supported Equipment or Components,” U.S. Nuclear Regulatory Commission, Washington, 

DC. 

32. Michael W. Salmon and Robert P. Kennedy, “Meeting Performance Goals by Use of Experience 

Data,” UCRL-CR-120813, prepared for Lawrence Livermore National Laboratory and 

U.S. Department of Energy, Existing Facilities Project Steering Group and Technical Review 

Team, Livermore, CA, December 1994.12 

33. ASCE/SEI 43-05, “Seismic Design Criteria for Structures, Systems, and Components in Nuclear 

Facilities,” Section 8.3.2, American Society of Civil Engineers, Reston, VA, January 2005.13

34. ASME Boiler and Pressure Vessel Code, Section III, Division 1, Article N-1213.1 of 

Nonmandatory Appendix N, “Dynamic Analysis Methods,” American Society of Mechanical 

Engineers, New York, NY, 2004. 

35. ASME Boiler and Pressure Vessel Code, Section III, “Rules for Construction of Nuclear Power 

Plant Components,” American Society of Mechanical Engineers, New York, NY, 2007. 

 

12 The report can be accessed by the public from the Internet Web site 

http://www.osti.gov/bridge/servlets/purl/101081-bmPSJ9/webviewable/101081.pdf

13 Copies of American Society of Civil Engineers (ASCE) standards may be purchased from ASCE Publications, 1801 

Alexander Bell Drive, Reston, VA 20191; telephone (800) 548-2723. Purchase information is available through the 

ASCE Web-based store at http://pubs.asce.org/books/.