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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 1.177, Revision 1, “An Approach for Plant-Specific, Risk-Informed Decisionmaking: Technical Specifications.”

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Donald Helton, Probabilistic Risk Assessment Branch, Division of Risk Analysis, Office of Nuclear Regulatory Research, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, telephone 301-251-7594 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 NRC 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 1.177, “An Approach for Plant-Specific, Risk-Informed Decisionmaking: Technical Specifications,” was issued with a temporary identification as Draft Regulatory Guide, DG-1227. This regulatory guide describes methods acceptable to the NRC staff for assessing the nature and impact of proposed technical specifications (TS) changes by considering engineering issues and applying risk insights. Licensees submitting risk information (whether on their own initiative or at the request of the staff) should address each of the principles of risk-informed regulation discussed in this regulatory guide. Licensees should identify how chosen approaches and methods (whether they are quantitative or qualitative, traditional or probabilistic), data, and criteria for considering risk are appropriate for making the necessary decision.

This regulatory guide provides the staff's recommendations for using risk information to evaluate changes to nuclear power plant TS completion times and surveillance frequencies in order to assess the impact of such proposed changes on the risk associated with plant operation. The guidance provided here does not preclude other approaches for requesting TS changes. Rather, this regulatory guide is intended to improve consistency in regulatory decisions related to TS changes in which the results of risk analyses are used to help justify the change. As such, this regulatory guide, the use of which is voluntary, provides guidance concerning an approach that the NRC has determined to be acceptable for analyzing issues associated with proposed changes to a plant's TS and for assessing the impact of such proposed changes on the risk associated with plant design and operation. Additional or revised guidance might be provided for new reactors (e.g., advanced light-water reactors) licensed under 10 CFR part 52, “Licenses, Certifications, and Approvals for Nuclear Power Plants.”

Other types of TS changes that follow the principles outlined in this regulatory guide may be proposed and will be considered on their own merit.

II. Further Information

In August 2009, DG-1227 was published with a public comment period of 60 days from the issuance of the guide. The public comment period closed on November 3, 2009. Electronic copies of Regulatory Guide 1.177, 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 4th day of May, 2011.

For the Nuclear Regulatory Commission.

Harriet Karagiannis,

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

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[FR Doc. 2011-11830 Filed 5-12-11; 8:45 am]