PiMAL

Welcome

Welcome to the landing page for Pimal.

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About

The PiMAL software is intended to be coupled with Monte Carlo N-Particle (MCNP) (Pelowitz et al. 2013) to allow radiation transport simulations for estimating radiation dose to humans. The newest version (6.0) also allows dose assessments to humans from medical sources in moveable phantoms of domestic pets (cats, dogs, and horses). The MCNP code can be run natively from the PiMAL interface, or externally in the MCNP command prompt via the generated MCNP input file. Both internal and external sources can be simulated in PiMAL selecting from a drop-down menu in the user interface. The user can also select an organ in the chosen animal in which radioactive material may be placed. Internal sources are assumed to be uniformly distributed within the selected organ. For external sources, in addition to a point source, the user can select the ICRP’s standard external exposure geometries (AP, PA, LLAT, RLAT, ISO). Advanced users of MCNP can add their own simulation characteristics to the PiMAL-generated MNCP input deck prior to running the code.

Computational models of the human anthropomorphic phantom have undergone progressive evolution since initial development more than sixty years ago (Xu 2014). Computational phantoms employed by the Nuclear Regulatory Commission (NRC) were largely based on a model published in 1974, which did not account for select organs (e.g., neck, esophagus) and tissues. This was exacerbated by inaccurate organ placement within the body (e.g., thyroid). Most notably, all the computational phantoms were assumed to be in the vertical-upright position, which continues to be a trend in the development of current computational phantoms. To assess the radiation dose in different configurations when needed, the mathematical phantom had been revised to enable freely moving abilities for arms and legs. The revised phantom is called PiMAL: Phantom with Moving Arms and Legs (Akkurt and Eckerman 2007).