United States Nuclear Regulatory Commission - Protecting People and the Environment

SNAP/RADTRAD 4.0: Description of Models and Methods (NUREG/CR-7220)

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Publication Information

Manuscript Completed: March 2016
Date Published: June 2016

Prepared by:
W.C. Arcieri, D.L. Mlynarczyk, and L. Larsen

Information Systems Laboratory, Inc.
11140 Rockville Pike, Suite 650
Rockville, MD 20852-3116

Mark Blumberg, NRC Technical Monitor
John Tomon, NRC Contracting Officer's Representative

Office of Nuclear Regulatory Research
U.S. Nuclear Regulatory Commission
Washington DC 20555-0001

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This report documents the models and methods used in the Symbolic Nuclear Analysis Package/RADionuclide Transport, Removal And Dose Estimation (SNAP/RADTRAD) code, which consists of the SNAP Model Editor graphical user interface (GUI), the SNAP/RADTRAD plugin and the RADionuclide Transport, Removal And Dose Estimation analytical code (RADTRAD-AC). The SNAP/RADTRAD code was developed for the U.S. Nuclear Regulatory Commission (NRC) Office of Nuclear Regulatory Research to estimate transport and removal of radionuclides and dose at selected receptors. The SNAP/RADTRAD code is used to estimate the radionuclide release from the containment using either the NRC TID-14844 or NUREG-1465 source terms and assumptions, or a user-specified table. In addition, the code can account for a reduction in the quantity of radioactive material released due to containment sprays, naturaldeposition, filters, and other engineered safety features. The code uses a combination of tables and numerical models of source term reduction phenomena to determine the time-dependent dose at user-specified locations for a given accident scenario. SNAP/RADTRAD can also be used to assess occupational radiation exposures, typically in the control room; to estimate site boundary doses; and to estimate dose attenuation due to modification of a facility or accident sequence.

Page Last Reviewed/Updated Friday, June 10, 2016