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Notice of Issuance of Regulatory Guide

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Nuclear Regulatory Commission.


Notice of issuance and availability of Regulatory Guide 1.47, Revision 1, “Bypassed and Inoperable Status Indication for Nuclear Power Plant Safety Systems.”

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Khoi Nguyen, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, telephone (301) 251-7453 or e-mail

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I. Introduction

The U.S. Nuclear Regulatory Commission (NRC) is issuing a revision to an existing guide in the agency's “Regulatory Guide” series. This series was developed to describe and make available to the public information such as methods that are acceptable to the Start Printed Page 9627NRC staff for implementing specific parts of the agency's regulations, techniques that the staff uses in evaluating specific problems or postulated accidents, and data that the staff needs in its review of applications for permits and licenses.

Revision 1 of Regulatory Guide 1.47 was issued with a temporary identification as Draft Regulatory Guide, DG-1205. This guide describes a method that the staff of the NRC considers acceptable for use in complying with the NRC's regulations with respect to bypassed and inoperable status indication for nuclear power plant safety systems.

The regulatory framework that the NRC has established for nuclear power plants consists of a number of regulations and supporting guidelines applicable to bypassed and inoperable status indication, including, but not limited to, General Design Criterion (GDC) 1, “Quality Standards and Records,” GDC 13, “Instrumentation and Control,” GDC 19, “Control Room,” GDC 21, “Protection System Reliability and Testability,” GDC 22, “Protection System Independence,” and GDC 24, “Separation of Protection and Control Systems,” as set forth in Appendix A, “General Design Criteria for Nuclear Power Plants,” to Title 10, Part 50, “Domestic Licensing of Production and Utilization Facilities,” of the Code of Federal Regulations (10 CFR part 50). GDC 1 requires that structures, systems, and components important to safety be designed and installed to quality standards commensurate with the importance-to-safety of the functions to be performed. GDC 13 requires that appropriate controls be provided to maintain variables and systems that can affect the fission process, the integrity of the reactor core, the reactor coolant pressure boundary, and the containment and its associated systems within prescribed operating ranges. GDC 19 requires that a control room be provided from which actions can be taken to operate the nuclear power unit safely under normal operating conditions. GDC 21 requires that the protection system be designed for high functional reliability and inservice testability. GDC 22 requires that the protection system be designed to ensure that the effects of normal operating, maintenance, and testing on redundant channels do not result in the loss of the protection function or be demonstrated to be acceptable on some other defined basis. GDC 24 requires that interconnection of the protection and control systems be limited to ensure that safety is not significantly impaired.

II. Further Information

In October 2008, DG-1205 was published with a public comment period of 60 days from the issuance of the guide. The public comment period closed on December 22, 2008. The staff's responses to the comments received are located in the NRC's Agencywide Documents Access and Management System (ADAMS) under Accession No. ML092330085.

Electronic copies of Regulatory Guide 1.47, Revision 1 are available through the NRC's public Web site under “Regulatory Guides” at​reading-rm/​doc-collections/​.

In addition, regulatory guides are available for inspection at the NRC's Public Document Room (PDR) located at Room O-1F21, One White Flint North, 11555 Rockville Pike, Rockville, Maryland 20852-2738. The PDR's mailing address is USNRC PDR, Washington, DC 20555-0001. The PDR can also be reached by telephone at (301) 415-4737 or (800) 397-4209, by fax at (301) 415-3548, and by e-mail to

Regulatory guides are not copyrighted, and NRC approval is not required to reproduce them.

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Dated at Rockville, Maryland, this 24th day of February 2010.

For the Nuclear Regulatory Commission.

Andrea D. Valentin,

Chief, Regulatory Guide Development Branch, Division of Engineering, Office of Nuclear Regulatory Research.

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[FR Doc. 2010-4435 Filed 3-2-10; 8:45 am]