A peer-reviewed journal published by K. N. Toosi University of Technology

Impact of polymer shielding layer on absorbed dose distribution in an 18 MeV LINAC treatment room: A FLUKA simulation study

Document Type : Research Article

Authors

1 Department of Nuclear Physics, Faculty of Basic Science, University of Mazandaran, P.O. Box 47415-416, Babolsar, Iran

2 Department of Physics, Faculty of Science, Ferdowsi University of Mashhad, P.O. Box 91775-1436, Mashhad, Iran

Abstract
In this study, using the FLUKA code (version 2011.2c.6), a 2300C/D linear accelerator head manufactured by Varian (18 MeV) were simulated within a radiation therapy room. Electron source and transporting particles using the FLUKA code from the source in each calculation replaced by an alternative photon which is an important aspect of the work. After verifying this alternative source, a composite shielding layer was considered as the interior covering of the treatment room, and the effect of six polymer-based shielding materials with different compositions on the photon and neutron doses at different locations was calculated. As a general conclusion from this research, using a polymer shielding layer of material including 32.5 wt% elastomer +60 wt% tungsten +7.5 wt% boron carbide on the interior of the roof, floor, and concrete walls of the treatment room is recommended, except for the second wall at the maze entrance. Additionally, we found that a 2 cm thickness of this shield is almost equivalent to 3 mm of pure lead. The optimized thickness depends on the specifications of the LINAC, its energy, the dimensions of the treatment room, and the thickness of the concrete walls which can be calculated based on these specifications.

Highlights

  • A 2300C/D linac head manufactured by Varian were simulated within a radiation therapy room.
  • An alternative photon source was utilized, instead of starting all the calculations from the primary electron beam.
  • Designing of a multilayer shield for the walls of treatment rooms, as the interior covering of the treatment room.
  • Using a polymer shielding layer significantly reduces photon and neutron absorbed dose.

Keywords


 

Copyright
RPE is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License (CC BY-NC 4.0).

Conflict of Interest

‎The authors declare no potential conflict of interest regarding the publication of this work‎.

Funding

‎The authors declare that no funds‎, ‎grants‎, ‎or other financial support were received during the preparation of this manuscript‎.

 

 
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Volume 6, Issue 4
Autumn 2025
Pages 1-16

  • Receive Date 14 January 2025
  • Revise Date 04 March 2025
  • Accept Date 13 March 2025