Regulatory Guide 3.9

Concrete Radiation Shields

ML12220A059
Person / Time
Issue date:	06/30/1973
From:	Office of Nuclear Regulatory Research, US Atomic Energy Commission (AEC)
To:
References
RG-3.009
Download: ML12220A059 (2)

U.S. ATOMIC ENERGY COMMISSION June 1973 REGULATORY

DIRECOoAT OF REGULATORY SANDARDS

GUIDE

REGULATORY GUIDE 3.9 CONCRETE RADIATION SHIELDS

A. INTRODUCTION

Design. Construction and Operation Criteria. and it was subsequently approved by the American National Section 20.101 of 10 CFR Part 20, "Exposure of Standards Institute- (ANSI) on December 22. IPQ2.

Individuals to Radiation in Restricted Areas," states that and designated ANSI N101.6-1972. The standard no licensee shall possess, use, or transfer licensed discusses aggregateo. design of concrete mixtures and material in such a manner as to cause any individual in a forms, placement of concrete, design and installation of restricted area to receive a dose in excess of the limits penetrations. embedments. metal liners, and penetration specified therein. Paragraph (c) of § 20.1 provides that plugs and outlines testing and quality assurance licensees, in addition to complying with the provisions needed to verify that the desired quality of requirements set forth in Part 20, make every reasonable design and construction has been achieved. The standard effort to maintain radiation exposures as far below the does not include detailed treatments of structural design limits specified in this part as practicable. or determination of shield thickness.

Concrete radiation shields can be installed in nuclear facilities such as hot laboratories, radiochemical plants,

C. REGULATORY POSITION

experimental facilities, and nuclear fuel fabrication plants to provide a barrier between personnel and The requirements and recommended practices radiation sources for the purpose cf reducing doses of contained in ANSI N101.6.1972, "Concrete Radiation ionizing radiation received by personnel to as low as Shields,"' are acceptable for the construction of practicable levels. This guide describes practices for the radiation shielding structures for hot laboratories.

construction of concrete radiation shielding structures radiochemical plants, experimental facilities, and nuclear for such nuclear facilities, which are acceptable to the fuel fabrication plants subject to the following:

Regulatory staff as methods of complying, in part, with Commission regulations with regard to reducing I. Section 2 of ANSI NI01.6-1972 lists applicable radiation exposures. Much of the information included documents which are intended to supplement this may be applicable to shielding structures for reactors standard. The specific applicability or acceptability of and other nuclear and nonnuclear facilities which require these listed documents has been or will be covered concrete radiation shields. separately in other regulatory guides or in Commission regulations. where appropriate.

B. DISCUSSION

2. Section 4.8 of ANSI N101.6-1972 delineates special Subcommittee ANS-li, Radioactive Materials precautions to be observed in the construction of Handling Facilities and Specialized Equipment. of the concrete radiation shields. Where steel or other metals American Nuclear Society has developed a standard are used as aggregate t,. increase the density of the presenting requirements and recommended practices for concrete, the metal should be of such type that it will the construction of concrete radiation shielding not cause hydrogen or other explosive gases to be structures and for certain elements of design that relate generated by reaction with the cement.

to problems unique to this type of structure. This standard was approved by the American National 'Copies may be obtained from the American Nuclear Standards Committee NIOi. Atomic Industry Facility Society. 244 East Ogden Avenue. Hinsdale, Illinois 60521.

USAEC REGULATORY GUIDES Coe Ofpubished guide may be obtaned by requem indca.ing the divisions desrIsd to the US. Atomic Erurgv Commission. Washington, D.C. 2054S.

Regulatory Guides or ISS*ed to describe ed mke lvwoiill4 to the public Atitenteio Director Of Regulatory Standards. Comnments and sol 1tions for menhods accepatmle to she AEC Regulatory staff of Imifes owtongspecific parts of inovernwts in these guides oe encouraged and should be sent to the Secretary the Comone.on5 - egat.:at1Os. CdP'isefe te-hrouee used by the seff in of the Commoonso. US. Atomic Energy Commssion. Washington. D.C. 206*4.

evaluating spec:fic ioblems 4; postulated eaecklnts. or to pro-ide guidance to Atlefstion: Chief. Public P.o*mengp Staff.

Ii*cnts. ReapulgO ry Guides *e not substitutes fw regulations end cooslaei s with them . not required. Methods and iolutions differenit from thoe at out in The guides ae issue in the following ten broad divisions:

the gu*id ill b4 acceptable if they porovde b at for this findings relu*iste to the resuano or continuance of a permit or Oicene by the Commisson. 1. Power Reactors

6. Produacts

2 Reseach end Test Reac ors

7. Transoortation

3. Fuels an Mt erials Facilities a. OccupefIO*l Helth Publi'shad guides will be revised eiw.odimi. w appropriate, to acornmndsa 4. Envrossmensl*ard siting g. Antitrust Review eninnent, and to reflect now informa~tion or eUperleis 5. Matarials end Plant Protection 1

0. General

3. Section 6.4 of ANSI NIOi.6-1972 does not explain 4. Section 8.7.1 of ANSI Ni0i.6-1972 states, in part.

how some of" the variables which are used in the that reinforcing steel or other means. be provided for N'

equations for bending moment and tensile stress are to transferring shear forces through a construction joini.

be determined. Therefore this section should not be used This requirement is not sufficient. Provision should be as a substitute for detailed thermal stress analysis in the made for adequate means of transferring shear and other desip of temperature reinforcement for control of forces through the joint.

cracking in specific concrete radiation shields.

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