Dose calculation for skin contamination
VARSKIN+ is used to calculate occupational dose to the skin resulting from exposure to radiation emitted from hot particles or other contamination on or near the skin. These assessments are required by Title 10 of the Code of Federal Regulations (10 CFR) 20.1201(c), which states that the assigned shallow dose equivalent is to the part of the body receiving the highest exposure over a contiguous 10 cm2 of skin at a tissue depth of 0.007 centimeters (7 mg/cm2).
As in previous versions, predefined source configurations are available in VARSKIN+ to allow simulations of point, disk, cylinder, sphere, slab, and syringe sources. Improvements to earlier versions include enhanced photon and electron dosimetry models, as well as models to account for airgap and cover materials. Both ICRP 38, “Radionuclide Transformations – Energy and Intensity of Emissions” (1983), and ICRP 107, “Nuclear Decay Data for Dosimetry Calculations” (2008), nuclide libraries are available at the user’s option and contain data on gamma rays, X rays, beta particles, internal conversion electrons, and Auger electrons.
With the release of VARSKIN+ three new physics modules are introduced: (1) wound dosimetry; (2) neutron dosimetry; and (3) eye dosimetry. Skin and wound dosimetry implement a new alpha dosimetry model for shallow skin assessments. VARSKIN+ can be used to perform wound dose assessments if the metabolic modeling and dosimetry methods are consistent with NRC regulations (e.g., use of 10 cm2 averaging area for skin dose assessments and tissue or organ weighting factors as defined in 10 CFR 20.1003).