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page title goes here Risk Assessment

BDCC What's New

The What's New section keeps users informed of toxicity value changes, exposure parameter changes, chemical-specific parameter changes, and any equation format changes. Please check this site frequently to be advised of any recent changes.

November 2020

  • A units conversion discrepancy was corrected for the submersion dose coefficients.

May 2018

  • While running the user provided option in site-specific mode, the calculator was showing duplicate records for C, H, Hg, I, Ni, Ru, S, and Te elemental isotopes. These duplicate records have been removed.

July 2017

  • When the secular equilibrium BDCC output option is selected, the BDCC Calculator now gives the option to show the individual progeny contributions for the BDCC (and dose) output.

May 2017

  • The +D and +E isotopes have been removed from the selection list. Now, a user may select the 'Assume secular equilibrium' to see PRG output for the entire chain.

January 2017

September 2015

  • New dose coefficients (DCFs) have been derived following FGR 12 and 13 and using the updated isotope list from ICRP 107. DCFs used are provided by the Center for Radiation Protection Knowledge. The main report is Calculations of Slope Factors and Dose Coefficients, and the tables of DCFs are in a separate appendix.
  • A forward dose assessment option was added to the calculator page. By selecting this option, the user is asked for media concentrations, and the dose is returned using BDCC equation inputs.
  • The radionuclide decay chains, provided in the calculator output, have been updated to reflect new decay information from ICRP 107. In addition to tabular results, a visual diagram depicts the branching fractions.
  • Updated FSURF values were added that account for multiple source depths (ground plane, 1cm, 5cm, 15cm, and infinite depth) and multiple building materials (wood, glass, concrete, drywall, and adobe mud brick were analyzed as well as 2 composite scenarios). Composite 1 is a drywall room with a glass window, wooden doors, and drywall walls. The floors for composite 1 are concrete, and the ceiling is drywall. Composite 2 is a concrete room with wooden doors, a drywall ceiling, and a concrete floor. Both composite cases used a homogeneous mix of material for the walls to represent the window and door mixed in with the wall. Finklea 2015 presents the analysis. See Section 4.3.10 of the User Guide for more details.

September 2014

March 2011

New generic tables are now available that address the issues listed in the previous entry.

August 2010

Many updates were performed to establish consistency with other calculators. These updates are mainly in appearance and in functionality. Area Correction Factor defaults have changed slightly, and new generic tables will be available soon.