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Radiological Assessment System for Consequence AnaLysis (RASCAL) Overview

The RASCAL code is a tool used by the Protective Measures Team in the U.S. Nuclear Regulatory Commission's (NRC's) Operations Center for making independent dose and consequence projections during radiological incidents and emergencies. RASCAL was developed by NRC over 25 years ago to provide a tool for the rapid assessment of an incident or accident at an NRC-licensed facility and aid decision-making such as whether the public should evacuate or shelter in place. RASCAL evaluates atmospheric releases from nuclear power plants, spent fuel storage pools and casks, fuel cycle facilities, and radioactive material handling facilities. Its data is not the only criterion used by the local authorities during an accident, but certainly an important one.


RASCAL has been continually upgraded and improved upon to include updated source term models, atmospheric transport models, nuclear power plant site-specific data and updated computer calculation methods.

  • RASCAL version 4.3.2, which was released in July 2016, is an update to RASCAL 4.3.1 that resolves coding issues identified by user feedback. Specifically, the update resolves RASCAL 4.3.1 coding issues with the UF6 and coolant release source terms for various fuel cycle and nuclear power plant scenarios. Additionally, this update resolved issues with the MetFetch Tool’s ability to retrieve and process meteorological data (observations and forecasts) due to changes in the security settings of new servers at the NWS.
    • RASCAL version 4.3.1, which was released in December 2014, is an update to RASCAL v4.3 that resolves coding issues identified by user feedback. Specifically, the update resolves RASCAL v4.3 coding issues with the generation of source terms for various nuclear power plant scenarios. Additionally, clarifying information was incorporated into the Spent Fuel Pool STDose module, Source-Term Import, Export and Merge Functions, and Meteorological Data Handling modules to assist the user with these RASCAL 4.3 functions.
      • RASCAL version 4.3, which was issued in September 2013, incorporated the NRC Near Term Task Force's lessons learned on the Fukushima Daiichi nuclear power plant accident in Japan. Some of these include updates to the atmospheric transport, dispersion and dose calculation (ATD) model to increase the RASCAL 4.3 domain from a 50 mile radius to a 100 mile radius, changes to the Source Term to Dose (STDose) models to include the option for long term station blackout (LTSBO) and 96 hour duration for the accident and the addition of Source Term Merge/Export option which allows users to assess the consequences from a multi-reactor event.
        • RASCAL version 4.2, which was issued in October 31, 2011, provided for large and small updates and fixes to the RASCAL 4.0 code. Some of these include updates to the dose conversion factors (DCFs), Source Term to Dose (STDose) models and the Field Measurement to Dose (FMDose) models and the addition of approved facility power-uprates to the facility database.
        RASCAL User Interface
        RASCAL Release Pathway Calculations
        RASCAL PWR Dry Containment - Leakage/Failure
        RASCAL Release Pathways
        RASCAL BWR Mk1 - Dry Well Direct
        RASCAL External Gamma + Beta Exposure Rate
        RASCAL 1st year Intermediate Phase TED