Document: NUREG-0800
Document ID: 55e187c7-8e17-41ed-a88e-0205d1317fb6
Document Type: srp
Title: - 12.4
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1315/ML13151A475.pdf
Revision Date: 2023-06
Chapter: 12
Section ID: 12.3
CFR Part: 
CFR Title: 

Content:
s from these vital areas. Consistent with the guidance contained in RGs 8.8 and 1.143, BTP 11-3 and SECY 94198, “Review of Existing Guidance Concerning the Extended Storage of Low- Level Radioactive Waste,” SSCs that are described in the application, should be designed to control leakage and facilitate access, operation, inspection, testing, and maintenance in order to maintain radiation exposures to operating and maintenance personnel as low as is reasonably achievable. Structures housing radioactive waste processing systems or components should be classified using the guidance for potential radiation exposure to site personnel, and to members of the public, to the extent it is not covered as part of the SRP Chapter 11 review, contained in RG 1.143. 2. Shielding The staff will evaluate the shielding design in terms of the assumptions used to calculate shield thickness, the calculational methods used, and the parameters chosen. A number of acceptable shielding calculational codes are available that are effective for determining the necessary shield thickness for gamma ray and combination neutron- gamma sources. The code description file of the Radiation Safety Information Computational Center (formerly the Radiation Shielding Information Center) at Oak Ridge National Laboratory includes most of the codes used by shield designers, which means that the codes have been tested and authenticated for operation but not for reliability and accuracy. Radiation shielding codes vary in complexity and accuracy from the relatively simple point-kernel methods, to the more complex discrete ordinates methods, to the still more rigorous Monte Carlo methods. The staff may use these codes, as necessary, to calculate dose rates for given shield designs and source strengths as a confirmation of the applicant’s method. The applicant’s shielding design is acceptable if the methods are comparable to commonly accepted shielding calculations and if assumptions regarding source terms,