Regulatory Guide 2.4

Review of Experiments for Research Reactors

ML12220A074
Person / Time
Issue date:	07/31/1976
From:	Office of Nuclear Regulatory Research, NRC/OSD
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References
RG-2.004
Download: ML12220A074 (4)

U.S. NUCLEAR REGULATORY COMMISSIONJuly 19 764* REGULATORY GUIDEOFFICE OF STANDARDS DEVELOPMENTREGULATORY GUIDE 2.4REVIEW OF EXPERIMENTS FOR RESEARCH REACTORS

A. INTRODUCTION

Section 50.36, "Technical Specifications," of 10 CFR Part 50,"Licensing of Production and Utilization Facilities," requires that eachapplicant for a license authorizing operation of a production or utiliza-tion facility include in his application proposed technical specifica-tions. If acceptable, these technical specifications, along with anyother such specifications that the Commission finds appropriate, are in-corporated into the facility license that is issued by the Commissionand are conditions of the license.Paragraph (c)(5), "Administrative controls," of § 50.36 of 10 CFRPart 50 requires that technical specifications for nuclear reactors in-.clude provisions relating to the organization and management procedures,recordkeeping, review and audit, and reporting necessary to ensureoperation of the facility in a safe manner. Section 50.59, "Changes,tests and experiments," of 10 CFR Part 50 permits each holder of a licenseauthorizing operation of a production or utilization facility to makechanges in the facility and procedures as described in the safety analysisreport (SAR) and to conduct tests or experiments not described in the SAR,without prior Commission approval, unless the proposed change, test, orexperiment involves a change in the technical specification incorporatedin the license or an unreviewed safety question.This guide describes procedures acceptable to the NRC staff for thelicensee's review and approval of experiments performed at research reactorfacilities.

B. DISCUSSION

Standard ANSI N401-1974 (ANS-15.6), "Review of Experiments forResearch Reactors,"* was prepared by Work Group ANS-15.6 and sponsored byCopies may be obtained from the American Nuclear Society, 244 East OgdenAvenue, Hinsdale, Illinois 60521.USNRC REGULATORY GUIDES Comments should be sent to the Secretary of the Commission. U.S. NuclearRegulatory Guide, are issued to describe and make available to the public Regulatory Commission. Washington. D.C. 20556. Attention. Docketing andmethods acceptable to the NRC staff of implementing specific parts of the Service Section.Commission's regulations, to delineate techniques used by the staff in evalu The guides are issued in the following ten broad divisionssting specific problems or postulated accidents. or to provide guidance to applicents. Regulatory Guides are not substitutes for regulations, and compliance 1. Power Reactors 6. Productswith them is not required. Methods and solutions different from those set out in 2. Research and Test Reactors 7. Transportationthe guides will be acceptable if they provide a basis for the findings requisite to 3. Fuels and Materials Facilities B. Occupational Healththe issuance or continuance of a permit or license by the Commission 4. Environmental and Siting 9. Antitrust ReviewComments and suggestions for improvements in these guides are encouraged 5. Materials and Plant Protection 10. Generalat all times, and guides will be revised, as appropriate, to accommodate comments and to reflect new information or experience. However. cummnenls on Copies of published guides may be obtained by written request indicating thethis guide. if received within about two months after its issuance will ho pat divisions desired to the U.S. Nuclear Regulatory Commission Washington. 0 C.ticularly useful in evaluating the need for an early revision 205665. Attention: Director. Office of Standards Development Subcommittee ANS-15 (Research Reactors) of the American Nuclear Society(ANS). This standard was approved by the American National StandardsCommittee N17, Research Reactors, Reactor Physics and Radiation Shielding,and its Secretariat in March 1974. It was subsequently approved anddesignated ANSI N401-1974 by the American National Standards Institute(ANSI) on November 19, 1974. The standard provides guidance for thelicensee's review and approval of experiments performed at research reactorfacilities by identifying substantive areas for each experiment that shouldbe reviewed to provide assurance that the experiment (1) falls within thelimits delineated in the technical specifications, (2) does not present anunreviewed safety question as defined in §50.59, "Changes, tests andexperiments," of 10 CFR Part 50, (3) does not constitute a threat to thehealth and safety of any individuals, and (4) does not constitute a hazardto the reactor facility or other equipment. In addition, this standardrecommends a system for classifying experiments to establish levels oflicensee review and approval commensurate with the level of risk inherentin the experiment. Both the requirements and the recommendations of thestandard have been evaluated by the staff in evaluating the acceptabilityof this standard.

C. REGULATORY POSITION

The requirements and recommendations provided in ANSI N401-1974,"Review of Experiments for Research Reactors," are generally acceptable tothe NRC staff. The guidance provides an adequate basis for the review andapproval of research reactor experiments performed in accordance with§§50.36 and 50.59 of 10 CFR Part 50, subject to the following:1. The last sentence of the paragraph -defining, "shall, should andmay," as given in Section 3, "Definitions," of ANSI N401-1974 should bemodified to read as follows: "To conform to this standard, experimentreview shall be performed in accordance with the standard's requirementsand recommendations."2. The definition of non-secured experiment, as given in Section 3,"Definitions," should be modified to read as follows: "Any eXteriment,experimental facility, or component of an experiment is considered to beunsecured when it is not secured as defined under secured experiment inSection 3."3. Subsection 4.1, "Classification System," should be modified byadding the following sentence: "The experiment classification system todetermine level of approval for the experiments should be reviewed andapproved by the Reactor Safety Committee designated in the TechnicalSpecifications."4. In addition to the experiment plan (Section 5, "The ExperimentalPlan"), there should also exist detailed procedures for carrying out an2.4-2 experiment, and these procedures should be reviewed as required by thefacility's technical specifications. A single experimental procedure maybe used for more than one exposure or more than one identical experiment,but such a procedure should expire after a specified interval.5. Subsection 6.1, "Review Procedure," should be modified by addingthe following sentence: "The experiment review procedure should bereviewed and approved by the Reactor Safety Committee designated in theTechnical Specifications."6. Paragraph (3) of Subsection 6.2, "Considerations," should bereplaced with the following: "Does the experiment meet all criteriaregarding reactivity effects? These criteria include assurance that (1)the potential reactivity worth of each secured experiment would be lessthan that value of reactivity which, if introduced as a positive stepchange, could result in a transient that would be likely to lead to dosesin any restricted or unrestricted area in excess of the limits set forthin 10 CFR Part 20; (2) the magnitude of the potential reactivity worth ofeach non-secured experiment would be less than that value which, if intro-duced as a positive step change in reactivity, would cause a violation ofa safety limit or of the minimum shutdown margin; and (3) the rate ofchange and magnitude of reactivity of any moveable experiment, moveableparts of experiments, or any combination of such experiments introducedby intentionally setting the experiments in motion relative to the reactorwould not exceed the capacity of the control system to providecompensation."7. In Subsection 6.3, "Review Personnel," the last paragraph shouldbe replaced with the following: "Members of the Committee should dis-qualify themselves from the review of experiments in which they aredirectly involved. They may act as consultants to the review group butshould not be involved with the final decision for approval or disapprovalof the experiment."8. The specific applicability or acceptability of items 1, 3, 4, and5 of Section 9, "References," of ANSI N401-1974 will be covered separatelyin other regulatory guides, where appropriate.

D. IMPLEMENTATION

The purpose of this section is to provide guidance to applicantsregarding the NRC staff's plans for using this regulatory guide in thereview of research reactor facility applications. The staff will use thisguide in evaluating applications submitted after the date shown below.However, all or part of this guide may be used by the staff to the extentreasonable and practicable for evaluating prior applications. Such use isusually reflected in the staff review questions and subsequent evaluations2.4-3 for specific cases. Backfitting action, if required, will be consideredseparately pursuant to Section 50.109 of 10 CFR PArt 50.Except in those cases in which the applicant proposes an acceptablealternative method for complying with specified portions of the Commission'sregulations, the method described herein will be used by the staff inevaluating applications in connection with research reactor facility con-struction permits, operating licenses, or proposed amendments theretosubmitted for approval after March 1, 1977.UNITED STATESNUCLEAR REGULATORY COMMISSIONWASHINGTON, D. C. 20555 POSTAGE AND FEES PAIDUNITED STATES NUCLEAROFFICIAL BUSINESS $300T O MPENALTY FOR PRIVATE USE, $300 EUARYCMISO2.4-4