How efficient are metal-polymer and dual-metals-polymer non-lead radiation shields?

Area of Science:

• Materials Science
• Medical Physics
• Radiation Protection

Background:

• Traditional lead shields for ionizing radiation attenuation are heavy and pose recycling challenges.
• Development of lighter, recyclable, and more efficient non-lead radiation shielding materials is ongoing.
• Polymer composites incorporating metallic compounds offer a potential alternative to lead.

Purpose of the Study:

• To evaluate the radiation shielding capabilities of novel non-lead materials.
• To compare the efficacy of single and dual metallic compound-polymer composites against lead shielding.

Main Methods:

• A Monte Carlo (MC)-based BEAMnrc code modeled a Philips X-ray machine.
• The MC model was validated using IPEM Report 78 standards.
• Shielding efficiency of various metallic compound-polyvinyl chloride (PVC) composites (e.g., BaSO₄-PVC, Bi₂O₃-PVC, Sn-PVC, W-PVC, Bi₂O₃-BaSO₄-PVC, Bi₂O₃-Sn-PVC, W-Sn-PVC, W-BaSO₄-PVC) was assessed by measuring absorbed doses in a water phantom and comparing them to 0.5 mm pure lead.

Main Results:

• Bismuth oxide-barium sulfate-PVC and tungsten-barium sulfate-PVC composites demonstrated high efficiency across most tested energies.
• Bismuth oxide-tin-PVC showed effectiveness at 60 keV.
• The bismuth oxide-barium sulfate-PVC dual-metal-PVC shield outperformed pure lead in the diagnostic X-ray energy range.

Conclusions:

• Single-metal-PVC and dual-metal-PVC shields are viable alternatives to lead for radiation protection.
• Combinations of low and high atomic number metals within PVC composites enhance shielding performance.
• These non-lead materials offer improved properties for radiation protection garments.