Regulatory Guide 5.28

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Evaluation of Shipper-Receiver Differences in Transfer of Special Nuclear Materials
ML003740063
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Issue date: 06/30/1974
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Office of Nuclear Regulatory Research
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RG-5.28
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June 1974 U.S. ATOMIC ENERGY COMMISSION

REGULATORY GUIDE

DIRECTORATE OF REGULATORY STANDARDS

REGULATORY GUIDE 5.28 EVALUATION OF SHIPPER-RECEIVER DIFFERENCES

IN THE TRANSFER OF

SPECIAL NUCLEAR MATERIALS

A. INTRODUCTION

receiver difference generally occurs because of errors introduced by sampling bulk materials and measuring Paragraph (g) of proposed § 70.58 of 10 CFR Part 70 weights or volumes and SNM concentrations. Additio.

(38FR3077) would require certain AEC licensees ally, a shipper-receiver difference could be the result of a authorized to possess special nuclear material to estab diversion, theft, unmeasured loss of SNM, or recording lish, maintain, and follow procedures for reviewing and mistake.

evaluating shipper-receiver differences. This guide identi fies concepts, principles, and methods that are accept The identification and evaluation of shipper-receiver able to the Regulatory staff for determining significant differences is one of the means of detecting diversion.

shipper-receiver differences. theft, loss, or misstatements of the amount of SNM

transferred. Additionally, such evaluation and subse

B. DISCUSSION

quent resolution will tend to limit the amount of material unaccounted for (MUF) transferred from one Statistical controls are required as an integral part of facility of another.

special nuclear materials control and accounting systems to assure that licensees of fuel processing and fuel Subcommittee N15-3 of the American National fabrication facilities effectively account for the special Standards Institute (ANSI) Standards Committee NI 5.

nuclear material they possess and identify losses when Methods of Nuclear Materials Control, has developed a they occur. An important statistical indicator of control standard that provides concepts and principles for the is an observed shipper-receiver difference, which results statistical evaluation of shipper-receiver differences in from comparing two independent determinations of the transfer of special nuclear materials. This standard.

transferred material. A shipper-receiver difference is the to be designated ANSI NI 5.17, "Concepts and Principles difference between the amount stated by the shipper as for the Statistical Evaluation of Shipper-Receiver Differ having been shipped and the amount stated by the ences in the Transfer of Special Nuclear Materials," has receiver as having been received.

been reviewed by Subcommittee NI 5-3.

Essential to a comprehensive evaluation of the signifi cance of this indicator are statistical techniques using This standard references the standard ANSI NI 5.16.

associated limits of error for testing whether detected "Limit of Error Concepts and Principles of Calculation differences may be attributable to measurement error. in Nuclear Materials Control," which defines limit of The power or discernibility of such significance tests error as twice the standard deviation of the estimates.

depends on the quality and amount of data evaluated. This is not always consistent with 10 CFR Part 70 and Regulatory Guide 5.3, "Statistical Terminology and The shipper and receiver of transferred material Notation for Nuclear Materials Management. which should make independent measurements to determine define limit of error as the uncertainty component used the amount of SNM in a shipment. A non-zero shipper- in constructing a 95% confidence interval.

USAEC REGULATORY GUIDES Copies of published guides may be obtained by request indocatng thr dvs~ons desired to the U.S. Atomic Energy Commission. Washington. D.C. 20545.

Regulatory Guidee Ms issued to describe end make available to the public Attention: Director of Regulatory Standards. Comments and suggestions for methods acceptable to the AEC Regultory staff of implementing specific parts of improvemants in these guides are encouraged and should be sent to the Secretary the Commission's regulations, to delinteete techniques .- ed by the staff in of the Commission. U.S. Atomic Energy Commission. Washington. D.C. 20545.

evltueting apecific problems or postulated accidents, or to provide guidance to Attention: Chief. Public Proceedings Staff.

appliceints. Regulatory Guides are not subetitutes for regulations and compliance with themr is not required. Melhods end solutions different from those set out in The guides are issued in the following ten broad divisions.

the guides will be acceptable if they provide a basis for the findings requisite to of a permit or license by the Commlssion. 2. Research and Test Reactors 7. Transportation the isuance or continuaers

3. Fuels and Materials Facilities 8. Occupational Heekh Published guides will be revised periodically, as appropriate, to accommodate 4. Environmental and Siting 9. Antitrust Review S. Materials end Plant P-otec'ion 10 General comments and to reflect new informaltion or experience.

C. REGULATORY POSITION

c. Replicate weighing data, The recommendations contained in the proposed d. Sampling scheme used and replicate sampling ANSI Standard N15.17, "Concepts and Principles for information, the Statistical Evaluation of Shipper-Receiver Differ ences in the Transfer of Special Nuclear Materials," e. Replicate analysis waaa.

Draft 5, dated April 10, 1974,1 are generally acceptable to the Regulatory staff for use in nuclear material f. Number of samples and elemental analyses going control and accounting procedures, except that in into each average value reported, section 4.6 of the standard the variances used in the evaluation of shipper-receiver differences should be g. Sampling errors and basis for the error estimates, considered as defined in Regulatory Guide 5.18, "Limit of Error Concepts and Principles of Calculation in h. Random and systematic errors for the elemental Nuclear Materials Control," which provides two clarifica analyses and basis for the error estimates, tions with regard to ANSI Standard N15.16-1974 having the same title. i. Sampling scheme for isotopic analyses, j. Number of isotopic analyses per lot, and In addition, the following should be done:

k. Random and systematic errors of the isotopic

1. Shipper-receiver differences should be reviewed and analyses and basis for the error estimates.

evaluated on an individual container, material batch, and shipment basis and on a transfer series of like-type 3. In regard to principle 4.3 of the standard, the material. Appropriate investigative and corrective action receiver's measurements, including sampling, should be should be taken to reconcile shipper-receiver differences made independent of the shipper's.

that are statistically significant at the 95% confidence level. 4. In regard to principles 4.2 and 4.4 of the standard, the procedure for evaluating shipper and receiver data

2. A statistically significant shipper-receiver difference should provide the capability to localize any detected warrants investigation to decide whether corrective diversion to specific transfer material batches and either action, e.g., reconciliation, is necessary or, more impor to a specific container or a specific group of containers.

tant, whether diversion or theft has occurred. The following measurement information should be available 5. Paragraphs 1.1 and 1.2 of the standard purposely in order to perform an adequate investigation: limit the scope of the standard. The detection of missing material and, in turn, the uncovering of diversion or a. Number of measurements of weight for each lot theft should be timely. Receipts should be piece and container. counted and item-identified for comparison with the shipment bill of lading as soon as possible, but in no case later than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after receipt. Also within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, b. Random and systematic errors for weighings and the integrity of tamper-safing devices should be verified, basis for the error estimates.

and receipts should be measured by weighing and, to the extent practical, by nondestructive analysis (NDA) for comparison with shipper's value

s. More accurate and

'Copies may be obtained from the Institute of Nuclear Materials precise measurements for completing AEC Form 741 Management, 505 King Avenue, Columbus, Ohio 43201, Attn: and for further data evaluation should be made as soon Mr. H. L. Toy. as practicable.

5.28-2