AbstractID: 8614 Title: A Computer Program for Nuclear Medicine Room Shielding
Calculations
As part of the process of designing a new clinical building that will house a large
Nuclear Medicine department including PET, a computer program was written in the
Java programming language to streamline the determination of the radiation shielding
requirements in the department.
The program takes as input a JPEG-formatted image of the floor plan or elevation
and calibrates its dimensions. The user specifies radioactive point sources by nuclide,
location, average activity, and the fraction of the work week that they are present. The
program calculates the exposure field over the entire area of the image, with and without
shielding. Shielding barriers are specified as straight line segments composed of a
thickness of lead or concrete. Zones having specific exposure limits may be specified.
Color-coded displays of the exposure field are displayed. The parameters of a particular
pixel in the exposure field image, including unshielded and shielded exposures, the most
restrictive constraint imposed by the exposure limitation zones, and a table of the
contributions to the exposure at that point by each source can be viewed. Tables of the
sources, shielding and exposure zones may be saved for incorporation into the
documentation of the design.
With this tool, a preliminary estimate of the required shielding for a project takes
only an hour. One can then modify shielding components and source characteristics to
interactively refine the estimate. Performing these estimates by hand consumes more time
and may not yield so thorough an analysis of the exposure field.