CCC-0761 RSAC-7.2.

1. NAME OR DESIGNATION OF PROGRAM:  RSAC-7.2

3. DESCRIPTION OF PROGRAM OR FUNCTION

The Radiological Safety Analysis Computer (RSAC) Program Version 7.2 (RSAC-7.2) is the newest version of the RSAC legacy code. RSAC-7.2 calculates the consequences of a release of radionuclides to the atmosphere. Users generate a fission product inventory from either reactor operating history or a nuclear criticality event. RSAC-7.2 models the effects of high-efficiency particulate air filters or other cleanup systems and calculates the decay and ingrowth during transport through processes, facilities, and the environment.

Doses are calculated for inhalation, air immersion, ground surface, ingestion, and cloud gamma pathways. RSAC-7.2 is used as a tool to evaluate accident conditions in emergency response scenarios, radiological sabotage events, and safety basis accident consequences. This users' manual contains the mathematical models and operating instructions for RSAC-7.2. Instructions, screens, and examples are provided to guide the user through the functions provided by RSAC-7.2. This program is designed for users who are familiar with radiological dose assessment methods.

4. METHODS

Radioactive releases from nuclear facilities may contribute to radiation exposure through a number of pathways: external exposures by direct radiation from plumes or deposited radionuclides; internal exposures from inhalation or ingestion of radioactive material. The Radiological Safety Analysis Computer (RSAC) Program Version 7.2 (RSAC-7.2) calculates the consequences of a release of radionuclides to the atmosphere. Using a personal computer, a user can generate a fission product inventory; calculate inventory decay and ingrowth; the Inventory during transport through processes, facilities, and the environment; model the downwind dispersion of the activity; and calculate doses to downwind individuals.

A fission product inventory can be calculated from reactor operating history and can be used to simulate a nuclear criticality accident. Radionuclide inventories can also be directly input into RSAC-7.2 if desired. Source term modeling allows for complete progeny ingrowth and decay during all accident phases. RSAC-7.2 release scenario modeling allows fractionation of the inventory by chemical group or element. RSAC-7.2 also models the effects of high-efficiency particulate air (HEPA) filters or other cleanup systems. RSAC-7.2's meteorological capabilities include Gaussian plume diffusion for Pasquill-Gifford, Hilsmeier-Gifford, and Markee models. RSAC-7.2 possesses the unique ability to model Class F fumigation conditions. Optionally, users can supply plume standard deviations (ss) or atmospheric diffusion (./Qs) to the code as input data. RSAC-7.2 also includes corrections for deposition (wet and dry) plume rise (jet and buoyant), resuspension, and release in a room and building wake. Doses are calculated through inhalation, immersion, ground surface, and ingestion pathways, and cloud gamma dose from semi-infinite plume model and finite plume model.

RSAC 7.2 calculates internal dose using the dose conversion factors and methodology from both ICRP 26/30 and ICRP 60/68/72. In addition to the calculation of lifetime dose, RSAC 7.2 calculates the acute 24 hour dose from radiological sabotage events.

RSAC 7.2 is a tool to evaluate accident conditions in emergency response scenarios and to evaluate of safety basis accident conditions.

5. RESTRICTIONS ON THE COMPLEXITY OF THE PROBLEM

RSAC-7.2 calculates inventories for fission products only. The nuclear data library contains selected activation products, actinides, and the daughters of actinides in addition to the fission products.

Inventories for activation products and actinides are not calculated by RSAC-7.2; however, they can be added to the inventory by using the radionuclide direct input section of the program. Subsequent sections of the program calculate the radioactive decay and doses from these additional radionuclides.

6. TYPICAL RUNNING TIME

The running time for RSAC-7.2 is dependent on the complexity of the run and the speed of the personal computer used.

- B. J. Schrader:
The Radiological Safety Analysis Computer Program (RSAC-7) User's Manual,
INL/EXT-09-15275 Rev. 1 (2010).

11. HARDWARE REQUIREMENTS

RSAC-7.2 runs on IBM compatible computers under Windows operating systems.  It was tested at RSICC on an Intel Xeon running Windows 7 and XP sp3.

13. SOFTWARE REQUIREMENTS

RSAC 7.2 is programmed in Fortran 77 using the Lahey compiler. The source files are not included in this distribution. Only binary copies of RSAC 7.2 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. RSAC 7.2 was validated for the Windows XP platform.

15. NAME AND ESTABLISHMENT OF AUTHOR

Contributed by: Radiation Safety Information Computational Center
                Oak Ridge National Laboratory
                Oak Ridge, Tennessee, USA
Developed by:   Idaho National Laboratory, Idaho Falls, Idaho, U. S. A

Executable Windows installer file: RSAC-7.2 files plus test cases
Electronic documentation