RadShield: semiautomated shielding design using a floor plan driven graphical user interface

Abstract

The purpose of this study was to introduce and describe the development of RadShield, a Java‐based graphical user interface (GUI), which provides a base design that uniquely performs thorough, spatially distributed calculations at many points and reports the maximum air‐kerma rate and barrier thickness for each barrier pursuant to NCRP Report 147 methodology. Semiautomated shielding design calculations are validated by two approaches: a geometry‐based approach and a manual approach. A series of geometry‐based equations were derived giving the maximum air‐kerma rate magnitude and location through a first derivative root finding approach. The second approach consisted of comparing RadShield results with those found by manual shielding design by an American Board of Radiology (ABR)‐certified medical physicist for two clinical room situations: two adjacent catheterization labs, and a radiographic and fluoroscopic (R&F) exam room. RadShield's efficacy in finding the maximum air‐kerma rate was compared against the geometry‐based approach and the overall shielding recommendations by RadShield were compared against the medical physicist's shielding results. Percentage errors between the geometry‐based approach and RadShield's approach in finding the magnitude and location of the maximum air‐kerma rate was within 0.00124% and 14 mm. RadShield's barrier thickness calculations were found to be within 0.156 mm lead (Pb) and 0.150 mm lead (Pb) for the adjacent catheterization labs and R&F room examples, respectively. However, within the R&F room example, differences in locating the most sensitive calculation point on the floor plan for one of the barriers was not considered in the medical physicist's calculation and was revealed by the RadShield calculations. RadShield is shown to accurately find the maximum values of air‐kerma rate and barrier thickness using NCRP Report 147 methodology. Visual inspection alone of the 2D X‐ray exam distribution by a medical physicist may not be sufficient to accurately select the point of maximum air‐kerma rate or barrier thickness.PACS number(s): 87.55.N, 87.52.‐g, 87.59.Bh, 87.57.‐s

Shielding Adequacy of Conventional X-ray Facilities in Kano Metropolis, Nigeria using RadShield Software

“…In the current study, as seen in Table 2A and 2B, the existing barrier thickness in all the rooms studied was less than the calculated barrier thickness with a ratio of less than 1, indicating that the shielding barrier thickness at different positions was enough to attenuate the primary and secondary radiation to design goal of 0.1 mGy/wk and 0.02 mGy/wk for the controlled and uncontrolled areas respectively. The findings are in agreement with the studies conducted by [4,5,6]. The Possible reasons for the similarity might be because of the involvement of experts during the construction of the x-ray room or overestimation of the shielding calculations.…”

Comparison of computed tomography shielding design methods using RadShield

“…When all required information has been entered, the user presses a button to calculate air kerma per week and barrier thickness at spatially sampled points along the separation lines and within regions of interest. The points at which the maximum value for air kerma and barrier thickness are found and displayed to the user and their corresponding values appear in a results window beneath the drawing workspace [6].…”

“…where B is the transmission factor, and θ is the x-ray angle of incidence, as employed in our previous paper, and described in the literature [6,12,13].…”

“…Alternatively, medical physicists can use vendor provided scatter isodose maps to calculate air kerma and barrier thicknesses [2,4,5]. This paper presents a thorough comparison of available shielding design methods through RadShield, a floor plan based graphical user interface (GUI) which performs spatially distributed calculations of air kerma and barrier thickness beyond user drawn barriers [6].…”

“…In our previous work, RadShield accurately performed radiation shielding design for radiographic and fluoroscopic exam rooms pursuant to NCRP Report 147 [6]. RadShield has been shown to produce precise shielding design results by rigorously sampling points beyond all barriers on an uploaded floor plan and reporting the maximum values for each barrier.…”