538
ST 6.3 –
Protección radiológica del público y el ambiente
METHODOLOGY FOR DETERMINATION OF SHIELDINGS OF
VETERINARY FACILITIES
Lava, Deise Diana*; da Silva Borges, Diogo;
Moreira, Maria de Lourdes; Ferreira Guimarães, Antonio Cesar
Instituto de Engenharia Nuclear. Brasil
* Responsible author, email: deisedy@gmail.com
In determining an effective method for shielding of rooms veterinary, was used in this study
methods of shielding commonly used in units that working with X-ray and radiation techniques.
The whole calculation procedure is based on traditional variables of transmission used for the
calculation of shielding in hospital units. The thickness of the materials used for primary and
secondary barrier room are obtained in order to respect the limits set by the National Nuclear
Energy Commission (CNEN). Calculations were arranged in an algorithm, allowing to use it as a
practical tool for quick and effective determination of materials and their thicknesses for
shielding veterinary facilities. The algorithm is characterized by determine transmission values
of the barriers and compare them with data obtained from "maps" of transmission given by
NCRP-148 Report ("Radiation Protection in Veterinary Medicine"). These "maps" were added to
the algorithm by means of interpolation techniques curves of materials that can be used for
shielding. Each interpolation generates about 100,000 points which are then used to plot a new
curve. The new curve is subjected to non-linear regression techniques, which makes possible to
obtain polynomials of degree nine and exponential equations. These equations, whose
variables consist of transmission of values, enable to trace all the points of this curves with high
precision. The data obtained from the algorithm are satisfactory to official data provided by the
NCRP and can contribute as a practical tool to verify the shielding of veterinary facilities that use
radiotherapy techniques and production of X-rays.