ML23055B024

DG-1386 (RG 1.73 Rev 2) Qualification of Safety-Related Actuators in Production and Utilization Facilities

ML23055B024
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Issue date:	05/12/2023
From:	Sheila Ray NRC/NRR/DEX/EEEB
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ML22356A003	List: ML23055B024 ML23055B028 ML23055B030
References
RG-1.073, Rev 2 DG-1386
Download: ML23055B024 (11)

Text

U.S. NUCLEAR REGULATORY COMMISSION DRAFT REGULATORY GUIDE DG-1386

Proposed Revision 2 to Regulatory Guide 1.73

Issue Date: May 2023 Technical Lead: Kayleh Hartage

QUALIFICATION OF SAFETY-RELATED ACTUATORS IN PRODUCTION AND UTILIZATION FACILITIES

A. INTRODUCTION

Purpose

This regulatory guide (RG) endorses, with exceptions, additions, and clarifications, the methods described in Institute of Electrical and Electronics Engineers (IEEE) Standard (Std.) 382-2019, IEEE Standard for Qualification of Safety-Related Actuators for Nucl ear Power Generating Stations and Other Nuclear Facilities (Ref. 1), as an acceptable process for demonstrating compliance with the applicable U.S. Nuclear Regulatory Commission (NRC) regulations for the en vironmental qualification of safety-related power-operated valve actuators in production and utilization facilities.

Applicability

This RG applies to licensees and applicants subject to Title 10 of the Code of Federal Regulations (10 CFR) Part 50, Domestic Licensing of Production and Utiliza tion Facilities (Ref. 2), and 10 CFR Part 52, Licenses, Certifications, and Approvals for Nu clear Power Plants (Ref. 3). Under 10 CFR Part 50, this RG applies to licensees of or applicants f or production and utilization facilities.

Under 10 CFR Part 52, this RG a pplies to applicants and holders of combined licenses, standard design certifications, standard design approvals, and manufacturing li censes.

Applicable Regulations

• 10 CFR Part 50

o 10 CFR 50.49, Environmental qualification of electric equipmen t important to safety for nuclear power plants, requires that holders or applicants for an operating license issued under 10 CFR Part 50 shall establish a program for the environm ental qualification of electric equipment as defined in 10 CFR 50.49. 10 CFR 50.49 also require s that holders of a combined license or a manufacturing license issued under Part 5 2 shall establish a program for the environmental qualification of electric equipment as de fined in 10 CFR 50.49.

This RG is being issued in draft form to involve the public in the development of regulatory guidance in this area. It has not received final staff review or approval and does not r epresent an NRC final staff po sition. Public comments are being solicited on this draft guide (DG) and its associated regulatory analysis. Comments should be accompanied by appropriate supporting data. Com ments may be submitted throu gh the Federal rulemaking Website, http://www.regulations.gov, by searching for draft regulatory guide DG-1386. Alternativel y, comments may be submitted to the Office of Administration, Mailstop: TWFN 7 A60M, U.S. Nuclear Regulatory Co mmission, Washington, DC 20555-000 1, ATTN: Program Management, Announc ements and Editing Staff. Comments must be submitted by the date indicated in the Federal Register notice.

Electronic copies of this DG, previous versions of DGs, and oth er recently issued guides are available through the NRCs public Website under the Regulatory Guides document collection of the NRC Library at https://www.nrc.gov/reading-rm/doc -collections/reg-guides/index.html. The DG is also available through the NRCs Agencywide Documents Acc ess and Management System (ADAMS) at http://www.nrc.gov/reading-rm/adams.html, under Accession No. ML23055B024. The regulatory analysis may be found in ADAMS under A ccession No. ML23055B028.

o 10 CFR Part 50, Appendix A, General Design Criteria for Nuclea r Power Plants, General Design Criterion (GDC) 1, Quality Standards and Records, requ ires, in part, that SSCs important to safety be designed a nd tested to quality standards commensurate with the importance of the safety functions to be performed. Where gener ally recognized codes and standards are used, they shall be identified and evaluated for applicability, adequacy, and sufficiency and shall be supplemented or modified as necessary to assure a quality product in keeping with the required safety function.

o 10 CFR Part 50, Appendix A, GDC 2, Design Bases for Protection against Natural Phenomena, requires, in part, that SSCs important to safety be designed to withstand the effects of natural phenomena without loss of capability to perf orm their safety functions.

o 10 CFR Part 50, Appendix A, GDC 4, Environmental and Dynamic E ffects Design Bases, requires, in part, that SSCs important to safety be designed to accommodate the effects of and to be compatible with the environmental conditions associated w ith normal operation, maintenance, testing, and postulated accidents, including loss-of-coolant accidents.

o 10 CFR Part 50, Appendix A, GDC 23, Protection System Failure Modes, requires that the protection system be designed to fail into a safe state or into a state demonstrated to be acceptable on some other defined basis if conditions such as di sconnection of the system, loss of energy, or postulated adverse environments are experienced.

o 10 CFR Part 50, Appendix B, Qua lity Assurance Criteria for Nuclear Power Plants and Fuel Reprocessing Plants, Criterion III, Design Control, requires, in part, design control measures for verifying the adequacy of the design.

o 10 CFR Part 50, Appendix B, Crite rion XI, Test Control, requires, in part, a test program to provide assurance that all testing required to demonstrate that SSCs will perform satisfactorily in service is performed in accordance with written procedures which incorporate the requirements and acceptance limits in applicable design doc uments.

o 10 CFR Part 50, Appendix B, Crite rion XVII, Quality Assurance Records requires, in part, the maintenance of sufficient records as evidence of quality assurance activities.

• 10 CFR Part 52

o 10 CFR 52.47(a)(13) requires that an applicant for a design cer tification must provide the list of electric equipment important to safety, as specified in 10 CFR 50.49(d).

o 10 CFR 52.79(a)(10) requires that an application for a combined license must provide a description of the program, and its implementation, for the environmental qualification of electric equipment, in accordance with 10 CFR 50.49(a). The app licant must also provide the list of electric equipment important to safety, that is require d by 10 CFR 50.49(d).

o 10 CFR 52.137(a)(13) requires that an applicant for standard de sign approval must provide the list of electric equipment important to safety, that is req uired by 10 CFR 50.49(d).

DG-1386, Page 2 Related Guidance

• RG 1.89, Environmental Qualification of Certain Electric Equip ment Important to Safety for Nuclear Power Plants (Ref. 4), describes a methodology to qual ify safety-related (Class 1E) electric equipment.

• RG 1.100, Seismic Qualification of Electrical and Active Mecha nical Equipment and Functional Qualification of Active Mechanical Equipment for Nuclear Power Plants (Ref. 5), describes methods considered acceptable for use in the seismic qualificat ion of electrical and mechanical equipment and the functional qualification of active mechanical equipment for nuclear power plants.

• RG 1.180, Guidelines for Evaluating Electromagnetic and Radio-Frequency Interference in Safety-Related Instrumentation and Control Systems (Ref. 6), describes the design, installation, and testing practices acceptable to the NRC staff for addressin g the effects of electromagnetic or radiofrequency interference and power surges on safety-related instrumentation and controls systems in a nuclear power plant environment.

• NUREG-1537, Parts 1 and 2, Guidelines for Preparing and Review ing Applications for the Licensing of Non-Power Reactors, issued February 1996 (Ref. 7), contains format and content guidance for non-power reactor applicants and licensees, as wel l as a standard review plan and acceptance criteria for the NRC staff.

• Final Interim Staff Guidance Augmenting NUREG-1537, Guideline s for Preparing and Reviewing Applications for the Licensing of Non-Power Reactors, Parts 1 and 2, for Licensing Radioisotope Production Facilities and Aqueous Homogeneous Reac tors, issued October 2012 (Ref. 8), gives format and content guidance for non-power aqueo us homogeneous reactor and radioisotope production facility applicants and licensees, as w ell as a standard review plan and acceptance criteria for NRC staff.

• Endorsement of Appendix A to Oak Ridge National Laboratory Report, Proposed Guidance for Preparing and Reviewing a Molten Salt Non-Power Reactor Applica tion, as Guidance for Preparing Applications for the Licensing of Non-Power Liquid Fu eled Molten Salt Reactors, dated November 18, 2020 (Ref. 9 ), endorses, with clarifications, Appendix A to ORNL/TM-2020/1478, Proposed Guidance for Preparing and Reviewi ng a Molten Salt Non-Power Reactor Application, issued July 2020 (Ref. 10), to support the review of non-power molten salt reactors.

Purpose of Regulatory Guides

The NRC issues RGs to describe methods that are acceptable to the staff for implementing specific parts of the agencys regulations, to explain techniqu es that the staff uses in evaluating specific issues or postulated events, and to describe information that the staff needs in its review of applications for permits and licenses. Regulatory guides are not NRC regulations and compliance with them is not required. Methods and solutions that differ from those set fort h in RGs are acceptable if supported by a basis for the issuance or continuance of a permit or license by the Commission.

DG-1386, Page 3 Paperwork Reduction Act

This RG provides voluntary guidance for implementing the mandat ory information collections in 10 CFR Parts 50 and 52 that are s ubject to the Paperwork Reduct ion Act of 1995 (44 U.S.C. 3501 et.

seq.). These information collections were approved by the Offic e of Management and Budget (OMB),

under control numbers 3150-0011 a nd 3150-0151, respectively. Send comments regarding this information collection to the FOIA, Library, and Information Co llections Branch (T6-A10M),

U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by email to Infocollects.Resource@nrc.gov, and to the OMB reviewer at: OMB Office of Information and Reg ulatory Affairs, (3150-0011 and 3150-0151), Attn: Desk Officer for the Nuclear Regulatory Commission, 725 17th Street, NW, Washington, DC, 20503; e-mail: oira_submissions@omb.eop.gov.

Public Protection Notification

The NRC may not conduct or sponsor, and a person is not require d to respond to, a collection of information unless the document re questing or requiring the col lection displays a currently valid OMB control number.

DG-1386, Page 4 B. DISCUSSION

Reason for Revision

The NRC issued Revision 1 of RG 1.73 in October 2013 (Ref. 12) to endorse IEEE Std. 382-2006, Standard for Qua lification of Safety-Related Actuators for Nuclear Power Generating Stations (Ref. 12). The IEEE sta ndard was revised in 2019. Thi s revision updates the RG to endorse the current version of IEEE Std. 382-2019, with certain clarificati ons, exceptions, and additions. This revision also clarifies that all production and utilization facilities a re within the scope of this RG.

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Background===

IEEE Std. 382-2019 was published on November 21, 2019. It was d eveloped by the Subcommittee on Qualification of Actuators (SC 2.3) of the IEEE Nuclear Power Engineering Committee and approved by the IEEE Standards Association Standards Board on November 7, 2019. This standard establishes criteria for the qualification of safety-related actuators and actuator components in nuclear power generating stations. The primary objective is to demonstr ate with reasonable assurance that safety-related actuators for which a qualified life or conditio n has been established can perform their safety function(s) without common-cause failures before, during, and after applicable design basis events (DBEs). Safety-related actuators and their interfaces must meet or exceed the equipment specification requirements. The IEEE standard specifies procedures for testin g under conditions that simulate (1) the postulated DBE conditions, including specified high-energy line breaks, loss-of-coolant accidents, main steam line breaks, and safe-shut down seismic earthquake events, and (2) those occurring under normal operating conditions.

The standard specifies procedures for accomplishing aging of co mponents to simulate the effects of long-term operation under nor mal and abnormal operating cond itions. These effects include exposure to thermodynamic environment (temperature, pressure, relative h umidity), fluid jet or spray environment, seismic and nonseismic vibration e nvironment, radiation environ ment, anticipated variations in input power source (electrical and mechanical), and electrical and me chanical characteristics. The standard provides guidance for how to in corporate manufacturers recommended maintenance intervals into the qualification process.

The examples and specific discussion in this RG primarily focus on power reactors. Other licensees of or applicants for p roduction and utilization facilities may also use and apply the guidance in this RG to help develop plans or programs that address meeting the agencys regulatory requirements for the qualification of safety-related actuators. In particular, t hese applicants and licensees may use the guidance to help verify adequacy of design for service.

Consideration of International Standards

The International Atomic Energy Agency (IAEA) works with member states and other partners to promote the safe, secure, and peaceful use of nuclear technologies. The IAEA develops Safety Requirements and Safety Guides for protecting people and the en vironment from harmful effects of ionizing radiation. This system of safety fundamentals, safety requirements, safety guides, and other relevant reports, reflects an international perspective on what constitutes a high level of safety. To inform its development of this RG, the NRC considered IAEA Safety Requ irements and Safety Guides pursuant to the Commissions International Policy Statement (Ref. 13) an d Management Directive and Handbook 6.6, Regulatory Guides (Ref. 14).

DG-1386, Page 5 The following IAEA Safety Standard was considered in the develo pment of the RG:

• IAEA Safety Standards Series No. SSG-69, Equipment Qualificati on for Nuclear Installations, issued 2021 (Ref. 15), addresses environmental qualification of equipment important to safety in nuclear power plants.

This RG endorses IEEE Std. 382-2019, which provides qualificati on methods based on the joint standard between the International Electrotechnical Commission (IEC) and IEEE: IEC/IEEE Std. 60780-323, Edition 1.0, 2016-02, IEC/I EEE International Standard - N uclear facilities -- Electrical equipment important to safety -- Qualification (Ref. 16). This joint sta ndard was created based on a collaborative international effort to harmoni ze standard qualification practices developed from IEC 60780:1998 (Ref.

17), Nuclear Power PlantsElectrical Equipment of the Safety S ystemQualification, and IEEE Std. 323-2003, (Ref. 18) IEEE Standard for Qualifying Class 1E Equipment for Nuclear Power Generating Stations.

Documents Discussed in Staff Regulatory Guidance

This RG endorses, in part, the use of one or more codes or sta ndards developed by external organizations, and other third-party guidance documents. These codes, standards, and third-party guidance documents may contain references to other codes, standards, or third-party guidance documents (secondary references). If a secondary reference has itself been incorporated by reference into NRC regulations as a requirement, then licensees and applicants mus t comply with that standard as set forth in the regulation. If the secondary reference has been endorsed in a RG as an acceptable approach for meeting an NRC requirement, then the standard constitutes a met hod acceptable to the NRC staff for meeting that regulatory requirement as described in the specific RG. If the secondary reference has neither been incorporated by refe rence into NRC regulations nor endorsed in a RG, then the secondary reference is neither a legally binding requirement nor a gener ic NRC-approved acceptable approach for meeting an NRC requirement. However, licensees and applicants m ay consider and use the information in the secondary reference, if appropriately justified, consistent with current regulatory practice, and consistent with applicable NRC requirements.

DG-1386, Page 6 C. STAFF REGULATORY GUIDANCE

The guidance in IEEE Std. 382-2 019 provides an acceptable appro ach to the NRC staff for meeting the agencys regulatory requirements for environmental qualification of safety-related power-operated valve actuators in production and utilization fa cilities, with the exceptions, additions, and clarifications listed in this section.

1. Section 2, Normative References, of IEEE Std. 382-2019 lists IEC/IEEE 60780-323, Nuclear facilities - Electrical equipment important to safety - Qualifi cation, as a normative reference, indispensable for the application of IEEE Std. 382-2019. IEC/IE EE 60780-323 should be replaced with RG 1.89, Environmen tal Qualification of Certain Electric Equipment Important to Safety for Nuclear Power Plants as a normative reference. Applicants and licensees should perform environmental qualification of safety-related actuators using the guidance in RG 1.89.

Acceptable qualification methods include type testing, analysis, or a combination thereof. Type testing is the preferred method of environmental qualification because other methods may be based on older or dissimilar equipment that may not be comparab le to the equipment being qualified. The staff finds that operational experience is not a n adequate method for qualifying equipment.

2. The radiological source term for qualification tests in a nucle ar radiation environment should be based on the source term methodology used in RG 1.89 and RG 1.183, Alternative Radiological Source Terms for Evaluating Design Basis Accidents at Nuclear P ower Reactors (Ref. 19). The containment size should be considered in each case. For exposed organic materials, calculations should consider neutron, beta, and gamma radiation.

3. IEEE Std. 382-2019, Section 15, Vibration Aging Test, states that the vibration aging test is intended to provide a vibratory environment that is representative of normal plant-induced vibration, including system ope rating transients and other dyna mic vibratory environments. The environmental qualification for power-operated valves should al so address flow-induced vibration caused by acoustic resources and hydraulic loading in the reactor, steam, and feedwater systems.

4. The NRC staff considers the gui dance in IEEE Std. 382-2019, Section 16, Seismic Simulation Test, as an acceptable method for the environmental qualificat ion of valve actuators, subject to the following exceptions, add itions, and clarifications:

4.1 Section 16.3(b) of IEEE Std. 382-2019 states: Each sweep shall be from 2 Hz to 35 Hz to 2 Hz, or from 2 Hz to 64 Hz to 2 Hz for hard rock sites or o ther enveloping frequency range specified by the user. Instead of that method, use the following method: Each sweep shall be from 2 Hz to 64 Hz to 2 Hz or, if the Required R esponse Spectra (RRS) has a frequency range exceeding 64 Hz, then the frequency sweep should be consistent with the RRS of the specific plant equipment.

4.2 Section 16.3(c) of IEEE Std. 382-2019 states: For actuator SSE [safe shutdown earthquake] qualification for line mounted application, perform a single frequency test by exposing the actuator to a series of single frequency sine-beat tests at the one-third octave interval test frequencies indicated in Figure 1, or other envel oping levels specified by the user. Instead, the users of this RG should perform a single fr equency test by exposing the actuator to a series of single frequency sine-beat tests at one-sixth octave interval test

DG-1386, Page 7 frequency to adequately identify resonance frequencies, or other enveloping levels specified by the user.

4.3 IEEE Std. 382-2019 does not provide a full set of the quali fication requirements for valve actuators. The users of this RG should address the other aspect s of the qualification process (such as seismic and functional qualification) for power operated valves, as described in RG 1.100, which accep ts the use of American Society of Mechanical Engineers (ASME) Standard QME-1-2017, Qualification of Active Mechanical Equipment Used in Nuclear F acilities (Ref. 20), with specific conditions. ASME Standard QME-1-2017 includes more stringent provisions for the functional qualification of power-operated valves than the ones specified in IEEE Std. 3 82-2019, including acceptable qualification methods, actuator grouping, actuator o utput capability testing, and extrapolation of actuator qualification.

DG-1386, Page 8 D. IMPLEMENTATION

The NRC staff may use this RG as a reference in its regulatory processes, such as licensing, inspection, or enforcement. However, the NRC staff does not intend to use the guidance in this RG to support NRC staff actions in a manner that would constitute bac kfitting as that term is defined in 10 CFR 50.109, Backfitting, and as described in NRC Management Direc tive 8.4, Management of Backfitting, Forward Fitting, Issue Finality, and Information Requests, (Re f. 21), nor does the NRC staff intend to use the guidance to affect the issue finality of an approval un der 10 CFR Part 52, Licenses, Certifications, and Approvals for Nuclear Power Plants. The staff also does not intend to use the guidance to support NRC staff ac tions in a manner that constitu tes forward fitting as that term is defined and described in Management Directive 8.4. If a licensee believ es that the NRC is using this regulatory guide in a manner inconsistent with the discussion in this Impl ementation section, then the licensee may file a backfitting or forward fitting appeal with the NRC in ac cordance with the process in Management Directive 8.4.

DG-1386, Page 9 REFERENCES 1

1. Institute of Electrical and Electronics Engineers (IEEE) Standa rd (Std.) 382-2019, IEEE Standard for Qualification of Safety-Related Actuators for Nucl ear Power Generating Stations and Other Nuclear Facilities, New York, New York, 2019. 2

2. U.S. Code of Federal Regulations (CFR), Domestic Licensing of Production and Utilization Facilities, Part 50, Chapter 1, Title 10, Energy.

3. CFR, Licenses, Certifications, and Approvals for Nuclear Power Plants, Part 52, Chapter 1, Title 10, Energy.

4. NRC, Regulatory Guide (RG) 1.89, Environmental Qualification o f Certain Electric Equipment Important to Safety for Nuclear P ower Plants, Washington, DC.

5. NRC, RG 1.100, Seismic Qualification of Electrical and Active Mechanical Equipment and Functional Qualification of Active Mechanical Equipment for Nuc lear Power Plants, Washington, DC.

6. NRC, RG 1.180, Guidelines for Evaluating Electromagnetic and R adio-Frequency Interference in Safety-Related Instrumentation and Control Systems, Washing ton, DC.

7. NRC, NUREG-1537, Parts 1 and 2, Guidelines for Preparing and R eviewing Applications for the Licensing of Non-Power Reactors, Washington DC, February 1 996, (ADAMS Accession No.: ML12156A069 and ML12156A075, respectively).

8. NRC, Final Interim Staff Guidance Augmenting NUREG-1537, Guide lines for Preparing and Reviewing Applications for the Licensing of Non-Power Reactors, Parts 1 and 2, for Licensing Radioisotope Production Facilities and Aqueous Homogeneous Reac tors, Washington DC, October 17, 2012, (ML12156A053).

9. NRC, Endorsement of Appendix A to Oak Ridge National Laboratory Report, Proposed Guidance for Preparing and Reviewing a Molten Salt Non-Power Reactor Application, as Guidance for Preparing Applications for the Licensing of Non-Po wer Liquid Fueled Molten Salt Reactors, Washington, DC, November 18, 2020 (ML20251A008).

10. Oak Ridge National Laboratory, ORNL/TM-2020/1478, Proposed Gui dance for Preparing and Reviewing a Molten Salt Non-Power Reactor Application, Oak Ridge, Tennessee, July 2020 (ML20219A771).

1 Publicly available NRC published documents are available electronically through the NRC Library on the NRCs public website at http://www.nrc.gov/reading-rm/doc-collections/ and through the NRCs Agencywide Documents Access and Management System (ADAMS) at http://www.nrc.gov/reading-rm/adams.html. For problems with ADAMS, contact the Public Document Room staff at 301-415-4737 or (800) 397-4209, or email pdr.resource@nrc.gov. The NRC Public Document Room (PDR), where you may also examine and order copies of publicly available documents, is open by appointment. To make an appointment to visit the PDR, please send an email to PDR.Resource@nrc.gov or call 1-800-397-4209 or 301-415-4737, between 8 a.m. and 4 p.m. eastern time (ET), Monday through Friday, except Federal holidays.

2 Copies of Institute of Electrical and Electronics Engineers (IEEE) documents may be purchased from the Institute of Electrical and Electronics Engineers Service Center, 445 Hoes L ane, PO Box 1331, Piscataway, NJ 08855, or through the IEEEs public Web site at http://www.ieee.org/publications_standards/index.html.

DG-1386, Page 10

11. NRC, RG 1.73, Revision 1, Qualification Tests for Safety-Relat ed Actuators in Nuclear Power Plants, Washington DC, October 2013 (ML13210A463).

12. IEEE, IEEE Std. 382-2006, Standard for Qualification of Safety -Related Actuators for Nuclear Power Generating Stations. New York, NY, 2006.

13. NRC, Nuclear Regulatory Commission International Policy Statement, Federal Register, Vol. 79, No. 132, pp. 39415-39418 (79 FR 39415), Washington DC, July 10, 2014.

14. NRC, Management Directive 6.6, Regulatory Guides, Washington, DC.

15. IAEA, IAEA Safety Standards Series No. SSG-69, Equipment Quali fication for Nuclear Installations, issued 2021 3

16. International Electrotechnical Commission (IEC)/IEEE, IEC/IEEE Std. 60780-323, Edition 1.0, 2016-02, IEC/IEEE International Standard - Nuclear facilities -- Electrical equipment important to safety - Qualification, issued 2016 4

17. IEC, IEC 60780:1998 Nuclear Power PlantsElectrical Equipment of the Safety System Qualification, October 1998.

18. IEEE, IEEE Std. 323-2003, IEEE Standard for Qualifying Class 1 E Equipment for Nuclear Power Generating Stations, New York, NY, 2003.

19. NRC, RG 1.183 Alternative Radiological Source Terms for Evalua ting Design Basis Accidents at Nuclear Power Reactors, Washington, DC.

20. American Society of Mechanical Engineers (ASME), QME-1-2017, Q ualification of Active Mechanical Equipment Used in Facilities, New York, NY 2017.

21. NRC, Management Directive 8.4, Management of Backfitting, Forw ard Fitting, Issue Finality, and Information Requests, Washington, DC.

3 Copies of International Atomic Energy Agency (IAEA) documents may be obtained through the IAEA Web site:

WWW.IAEA.Org/ or by writing the International Atomic Energy Agency, P.O. Box 100 Wagramer Strasse 5, A-1400 Vienna, Austria.

4 Copies of International Elec trical Commission (IEC) documents may be obtained through the IEC Web site:

http://www.iec.ch/ or by writing the IEC Central Office at P.O. Box 131, 3 Rue de Varembé, 1211 Geneva, Switzerland, Telephone +41 22 919 02 11.

DG-1386, Page 11