RSICC Home Page RSAC-6.2

RSICC CODE PACKAGE CCC-125

1.         NAME AND TITLE

RSAC-6.2: Radiological Safety Analysis Code System.

AUXILIARY ROUTINES

WINRP 2.0, a windows based overlay to RSAC-6.2, assists users in creating, running and viewing RSAC-6.2 input files. WINRP 2.0 is written in Visual Basic and runs on any personal computer that supports the RSAC-6.2 code. With WINRP 2.0 a user can modify input files easily. It also allows the user to insert, edit, add, copy, move, or delete sets of instructions for RSAC-6.2. WINRP 2.0 stores each problem set in a separate file. WINRP 2.0 checks all fields to ensure that data are in an appropriate range for the variable and that there is consistency in an input series.

2.         CONTRIBUTOR

Idaho National Laboratory, Idaho Falls, Idaho.

3.         CODING LANGUAGE AND COMPUTER

Fortran 77; PC 586 (C00125/PC586/03).

4.         NATURE OF PROBLEM SOLVED

RSAC-6.2 can be used to model complex accidents and radiological consequences to individuals from the release of radionuclides to the atmosphere. A user can generate a fission product inventory; decay and ingrow the inventory during transport through processes, facilities, and the environment; model the downwind dispersion of the activity; and calculate doses to downwind individuals. Doses are calculated through the inhalation, immersion, ground surface and ingestion pathways. New to RSAC-6.2 are the abilities to calculate inhalation from release to a room, inhalation from resuspension of activities, and a new model for dry deposition. Doses can now be calculated as close as 10 meters from the release point. RSAC-6.2 has been subjected to extensive independent verification and validation for use in performing safety-related dose calculations to support safety analysis reports. WinRP 2.0, a windows based overlay to RSAC-6.2, assists users in creating and running RSAC-6.2 input files. RSAC-6, Rev. 6.2 (03/11/02) corrects an earlier issue with RSAC-6, compiled with F77L-EM/32 Fortran 77 Version 5.10, which would not allow the executable to run with XP or VISTA Windows operating systems. Because this version is still in use at some facilities, it is being released through RSICC in addition to the new RSAC 7 (CCC-761).

5.         METHOD OF SOLUTION

A fission product inventory can be calculated from the reactor operating history or to simulate a nuclear criticality accident. Radionuclide inventories can also be directly input into RSAC if desired. Source term modeling allows for complete progeny ingrowth and decay during all accident phases. Release scenario modeling allows fractionation of the inventory by chemical group or element. The effects of high-efficiency particulate air (HEPA) filters or other cleanup systems can be modeled. RSAC6 calculates meteorological dispersion in the atmosphere using Gaussian plume diffusion for Pasquill‑Gifford, Hilmeier‑Gifford and Markee models. A unique capability is the ability to model Class F fumigation conditions, the meteorological condition that causes the highest ground level concentrations from an elevated release. Doses may be calculated for various pathways including inhalation, ingestion, ground surface, air immersion, and water immersion pathways. Dose calculations may be made for either acute or chronic releases. Internal doses (inhalation and ingestion) are calculated using the ICRP-30 model with dose conversion factors from Federal Guidance Report No. 11 (EPA 1988). External factors are calculated from Federal Guidance Report No. 12 (EPA 1993). This is a significant move from the factors that were used in RSAC5. See page 13 of the user’s manual for more information on changes in RSAC-6.

6.         RESTRICTIONS OR LIMITATIONS

RSAC-6.2 does not calculate inventories for activation products or actinides. A maximum of eight downwind distances and fifteen crosswind distances may be selected for dose calculations on a single run. Plume standard deviations are calculated only for the range of 1.E+1 to 1.E+5 m. Users are cautioned to use the finite plume model for cloud gamma calculations rather than air immersion model when semi-infinite conditions do not exist.

7.         TYPICAL RUNNING TIME

The running time for RSAC-6.2 is dependent on the complexity of the run and the speed of the personal computer used. 

8.         COMPUTER HARDWARE REQUIREMENTS

RSAC-6.2 runs on Pentium computers under Windows operating systems. It was tested at RSICC on a Pentium 4 running Windows XP.

9.         COMPUTER SOFTWARE REQUIREMENTS

RSAC-6.2 is programmed in Fortran 77 using the LAHEY compiler and Visual Basic 6.2. The source files are not included in this distribution. Only binary copies of RSAC-6.2 and its libraries are issued to users to prevent user changes to the program that would invalidate the extensive validation and verification. Each page of output contains the program version number, the program serial number, and the date and time the run was made. This release was validated for Windows XP.

10.        REFERENCES

a)   Included in document:

B. J. Schrader, RSAC 6.2 with WinRP 2.0 User Manual, INL/EXT-05-00642 (2005).

b)   Included in distribution in PDF directory:

D. R. Wenzel and B. J. Schrader, The Radiological Safety Analysis Computer Program (RSAC 6) User's Manual, INEEL/EXT-01-00540 (2001).

c)   Background information:

Verification and Validation of RSAC-6, INEEL report (2001).

11.        CONTENTS OF CODE PACKAGE

Included are the referenced document in 10.a and a CD with a compressed Windows zip file. The CD contains RSAC-6.2 Windows executable files plus test cases and documentation.

12.        DATE OF ABSTRACT

August 1971; revised December 1984, May 1994, October 2001, February 2008, December 2009.

KEYWORDS:     AIRBORNE; FISSION PRODUCT INVENTORY; INTERNAL DOSE; RADIOLOGICAL SAFETY; KERNEL; FISSION PRODUCTS; MICROCOMPUTER