D9.106 – Guidelines for implementing the workplace geometry and the radiation field map in the dosimetry application: Part 1: Workplace geometry

This document provides guidelines on how to characterize the radiation field for either interventional radiology workplaces: C-arm, protective shields; and mixed gamma-neutron workplaces. As regards interventional radiology workplaces the required information and the foreseen data sources have been identified. In particular, for the calculations the most reliable way to gather the required information is the RDSR report. This information is of interest for the two dosimetric approaches considered in the project. The PODIUM application up-loads the information from the RDSR and transforms it to be used as input for the dose calculation. A sensitivity analysis on the impact of different parameters on the operator dose has been carried out to optimize the size of the radiation field lookup table. For neutrons, the real time Monte Carlo method is not feasible due to the time constrains being unrealistic for such computationally intensive simulations, as well as problems with the calculation method itself. Therefore, a lookup method is used where the workplace simulations must be performed before the application of the proposed real time dosimetry system. The workplace characterization will result in lookup tables defined on grids with locational- and directional- (the facing direction of the individual) dependent effective dose conversion coefficients. This system will depend on a monitor to scale the lookup value with the instrument’s reading. The lookup table is highly dependent on the workplace and the neutron sources, but can be calculated in advance using the Monte Carlo method without the time constrains of a real-time system. For these calculations to be performed detailed knowledge of the sources and workplace environment are needed.