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Draft Regulatory Guide; Issuance, Availability

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The U.S. Nuclear Regulatory Commission (NRC) has issued for public comment a draft revision to an existing guide in the agency's Regulatory Guide Series. This series has been developed to describe and make available to the public such information as methods that are acceptable to the NRC staff for implementing specific parts of the NRC'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.

The draft Revision 2 of Regulatory Guide 1.152, entitled “Criteria for Use of Computers in Safety Systems of Nuclear Power Plants,” is temporarily identified by its task number, DG-1130, which should be mentioned in all related correspondence. The regulatory guide describes a method that is acceptable to the NRC staff for complying with the NRC's regulations for promoting high functional reliability and design quality for the use of computers in safety systems of nuclear plants. For the purposes of DG-1130, the term “computer” means a system that includes computer hardware, software, firmware, and interfaces.

The guidance provided in DG-1130 is consistent with General Design Criterion (GDC) 21, “Protection System Reliability and Testability,” of 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). Among other things, GDC 21 requires that protection systems (or safety systems) must be designed for high functional reliability, commensurate with the safety functions to be performed. In addition, Criterion III, “Design Control,” of appendix B, “Quality Assurance Criteria for Nuclear Power Plants and Fuel Reprocessing Plants,” to 10 CFR part 50 requires, among other things, that quality standards must be specified, and design control measures must be provided, for verifying or checking the adequacy of design.

The new draft regulatory guide DG-1130 also contains the staff's regulatory position on the “Standard Criteria for Digital Computers in Safety Systems of Nuclear Power Generating Stations,” [1] which the Nuclear Power Engineering Committee of the Institute of Electrical and Electronics Engineers (IEEE) has promulgated as IEEE Std 7-4.3.2-2003. The NRC staff has collaborated in the development of IEEE Std 7-4.3.2-2003 to ensure that the guidance provided by the consensus standard is consistent with the NRC's regulations. This standard evolved from IEEE Std 7-4.3.2-1993 and reflects advances in digital technology. It also represents a continued effort by IEEE to support the specification, design, and implementation of computers in safety systems of nuclear power plants. In addition, IEEE Std 7-4.3.2-2003 specifies computer-specific requirements to supplement the criteria and requirements of IEEE Std 603-1998, “Standard Criteria for Safety Systems for Nuclear Power Generating Stations.”

It is the staff's intent to endorse IEEE Std 7-4.3.2-2003, with certain exceptions, in the final regulatory guide as an acceptable method for satisfying the NRC's regulations with respect to (1) high functional reliability and design requirements for computers used in safety systems of nuclear power plants, Start Printed Page 75360and (2) independence between safety software and nonsafety software residing on the same computer.

The NRC staff is soliciting comments on draft regulatory guide DG-1130, and comments may be accompanied by relevant information or supporting data. Please mention DG-1130 in the subject line of your comments. Comments on this draft regulatory guide submitted in writing or in electronic form will be made available to the public in their entirety on the NRC's rulemaking Web site. Personal information will not be removed from your comments. You may submit comments by any of the following methods.

Mail comments to: Rules and Directives Branch, Office of Administration, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001.

E-mail comments to: You may also submit comments via the NRC's rulemaking Web site at Address questions about our rulemaking Web site to Carol A. Gallagher (301) 415-5905; email

Hand-deliver comments to: Rules and Directives Branch, Office of Administration, U.S. Nuclear Regulatory Commission, 11555 Rockville Pike, Rockville, Maryland 20852, between 7:30 a.m. and 4:15 p.m. on Federal workdays.

Fax comments to: Rules and Directives Branch, Office of Administration, U.S. Nuclear Regulatory Commission at (301) 415-5144.

Requests for technical information about draft regulatory guide DG-1130 may be directed to Satish Aggarwal, Senior Program Manager, at (301) 415-6005 or via email to

Comments would be most helpful if received by February 11, 2005. Comments received after this date will be considered if it is practical to do so, but the NRC is able to ensure consideration only for comments received on or before this date. Although a time limit is given, comments and suggestions in connection with items for inclusion in guides currently being developed or improvements in all published guides are encouraged at any time.

Electronic copies of the draft regulatory guide are available through the NRC's public Web site under Draft Regulatory Guides in the Regulatory Guides document collection of the NRC's Electronic Reading Room at​reading-rm/​doc-collections/​. Electronic copies are also available in the NRC's Agencywide Documents Access and Management System (ADAMS) at​reading-rm/​adams.html, under Accession No. ML043170314. Note, however, that the NRC has temporarily suspended public access to ADAMS so that the agency can complete security reviews of publicly available documents and remove potentially sensitive information. Please check the NRC's Web site for updates concerning the resumption of public access to ADAMS.

In addition, regulatory guides are available for inspection at the NRC's Public Document Room (PDR), which is located at 11555 Rockville Pike, Rockville, Maryland; 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) 397-4205, by fax at (301) 415-3548; and by email to Requests for single copies of draft or final guides (which may be reproduced) or for placement on an automatic distribution list for single copies of future draft guides in specific divisions should be made in writing to the U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, Attention: Reproduction and Distribution Services Section; by email to; or by fax to (301) 415-2289. Telephone requests cannot be accommodated. Regulatory guides are not copyrighted, and Commission approval is not required to reproduce them.

(5 U.S.C. 552(a)).

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Dated at Rockville, Maryland, this 9th day of December, 2004.

For the Nuclear Regulatory Commission.

Michael E. Mayfield,

Director, Division of Engineering Technology, Office of Nuclear Regulatory Research.

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1.  IEEE publications may be purchased from the IEEE Service Center, 445 Hoes Lane, Piscataway, NJ 08854.

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[FR Doc. 04-27493 Filed 12-15-04; 8:45 am]