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Withdrawal of Regulatory Guide 8.5

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Nuclear Regulatory Commission.


Withdrawal of Regulatory Guide 8.5, “Criticality and Other Interior Evacuation Signals.”

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Sheena A. Whaley, U.S. Nuclear Regulatory Commission, Office of Nuclear Material Safety and Safeguards, Division of Fuel Cycle Safety and Safeguards, Technical Support Branch, Washington, DC 20555-0001, telephone: 301-492-3200; or by e-mail to

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I. Introduction

The U.S. Nuclear Regulatory Commission (NRC) is withdrawing Regulatory Guide 8.5, “Criticality and Other Interior Evacuation Signals,” Revision 1, issued March 1981. Regulatory Guide 8.5 endorses the American National Standards Institute/American Nuclear Society (ANSI/ANS) Standard N2.3-1979 “Immediate Evacuation Signal for Use in Industrial Installations,” published September 13, 1979.

In 1986, the ANS Standards Subcommittee combined ANSI/ANS-N2.3-1979 with ANSI/ANS-8.3-1986, “Criticality Accident Alarm System” and withdrew ANSI/ANS-N2.3-1979. In December 2010 the NRC issued Revision 2 of Regulatory Guide 3.71, “Nuclear Criticality Safety Standards for Fuels and Material Facilities” which endorses multiple ANSI/ANS standards including ANSI/ANS-8.3-1997, (Reaffirmed in 2003).

The combining of ANSI/ANS-N2.3 and ANSI/ANS-8.3 by the ANS and the endorsement of ANSI/ANS-8.3 by the NRC in Revision 2 of Regulatory Guide 3.71 has made Regulatory Guide 8.5 unnecessary. Consequently, the NRC is withdrawing it and recommends using the guidance in ANSI/ANS-8.3-1997 as endorsed with exceptions by Revision 2 of Regulatory Guide 3.71 instead.

II. Further Information

The withdrawal of Regulatory Guide 8.5 does not alter any prior or existing licensing commitments based on their use. The guidance provided in this regulatory guide is no longer necessary. Regulatory guides may be withdrawn when their guidance no longer provides useful information, or is superseded by technological, congressional actions, or other events.

Guides are revised for a variety of reasons, and the withdrawal of a regulatory guide should be thought of as the final revision of the guide. Although a regulatory guide is withdrawn, current licensees may continue to use it, and withdrawal does not affect any existing licenses or agreements. Withdrawal means that the guide should not be used for future NRC licensing activities. Changes to existing licenses can be accomplished using other regulatory products.

Regulatory guides and publicly available NRC documents are available electronically through the Electronic Reading Room on the NRC's public Web site at:​reading-rm/​doc-collections/​. The documents can also be viewed on-line for free or printed for a fee in 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 1-800-397-4209; fax 301-415-3548; or 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 3rd day of February, 2011.

For the Nuclear Regulatory Commission.

Thomas H. Boyce,

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

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[FR Doc. 2011-6665 Filed 3-21-11; 8:45 am]