Regulatory Guide 3.9
| 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
GUIDE DIRECOoAT
OF REGULATORY
SANDARDS REGULATORY
GUIDE 3.9 CONCRETE RADIATION
SHIELDS
A. INTRODUCTION
Section 20.101 of 10 CFR Part 20, "Exposure of Individuals to Radiation in Restricted Areas," states that no licensee shall possess, use, or transfer licensed material in such a manner as to cause any individual in a restricted area to receive a dose in excess of the limits specified therein. Paragraph (c) of § 20.1 provides that licensees, in addition to complying with the requirements set forth in Part 20, make every reasonable effort to maintain radiation exposures as far below the limits specified in this part as practicable.
Concrete radiation shields can be installed in nuclear facilities such as hot laboratories, radiochemical plants, experimental facilities, and nuclear fuel fabrication plants to provide a barrier between personnel and radiation sources for the purpose cf reducing doses of ionizing radiation received by personnel to as low as practicable levels. This guide describes practices for the construction of concrete radiation shielding structures for such nuclear facilities, which are acceptable to the Regulatory staff as methods of complying, in part, with Commission regulations with regard to reducing radiation exposures.
Much of the information included may be applicable to shielding structures for reactors and other nuclear and nonnuclear facilities which require concrete radiation shields.
B. DISCUSSION
Subcommittee ANS-li, Radioactive Materials Handling Facilities and Specialized Equipment.
of the American Nuclear Society has developed a standard presenting requirements and recommended practices for the construction of concrete radiation shielding structures and for certain elements of design that relate to problems unique to this type of structure.
This standard was approved by the American National Standards Committee NIOi. Atomic Industry Facility Design. Construction and Operation Criteria.
and it was subsequently approved by the American National Standards Institute- (ANSI) on December 22. IPQ2.and designated ANSI N101.6-1972.
The standard discusses aggregateo.
design of concrete mixtures and forms, placement of concrete, design and installation of penetrations.
embedments.
metal liners, and penetration plugs and outlines testing and quality assurance provisions needed to verify that the desired quality of design and construction has been achieved.
The standard does not include detailed treatments of structural design or determination of shield thickness.
C. REGULATORY
POSITION The requirements and recommended practices contained in ANSI N101.6.1972, "Concrete Radiation Shields,"'
are acceptable for the construction of radiation shielding structures for hot laboratories.
radiochemical plants, experimental facilities, and nuclear fuel fabrication plants subject to the following:
I. Section 2 of ANSI NI01.6-1972 lists applicable documents which are intended to supplement this standard.
The specific applicability or acceptability of these listed documents has been or will be covered separately in other regulatory guides or in Commission regulations.
where appropriate.
2. Section 4.8 of ANSI N101.6-1972 delineates special precautions to be observed in the construction of concrete radiation shields. Where steel or other metals are used as aggregate t,. increase the density of the concrete, the metal should be of such type that it will not cause hydrogen or other explosive gases to be generated by reaction with the cement.'Copies may be obtained from the American Nuclear Society. 244 East Ogden Avenue. Hinsdale, Illinois 6052
1. USAEC REGULATORY
GUIDES Coe Of pubished 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 owtong specific 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.
D.C. evaluating spec:fic ioblems 4; postulated eaecklnts.
or to pro-ide guidance to Atlefstion:
Chief. Public Staff.Ii**cnts.
ReapulgO ry Guides 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 ill b4 acceptable if they porovde b at for this findings 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.
Helth Publi'shad guides will be revised eiw.odimi.
w appropriate, to acornmndsa
4.
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 how some of" the variables which are used in the equations for bending moment and tensile stress are to be determined.
Therefore this section should not be used as a substitute for detailed thermal stress analysis in the desip of temperature reinforcement for control of cracking in specific concrete radiation shields.4. Section 8.7.1 of ANSI Ni0i.6-1972 states, in part.that reinforcing steel or other means. be provided for transferring shear forces through a construction joini.This requirement is not sufficient.
Provision should be made for adequate means of transferring shear and other forces through the joint.N'3.9-2