SU-E-T-270: Optimized Shielding Calculations for Medical Linear Accelerators (LINACs).

Area of Science:

• Medical Physics
• Radiotherapy Engineering
• Radiation Protection

Background:

• Medical linear accelerators (LINACs) require precise radiation shielding to protect personnel and the public.
• Ensuring effective shielding is crucial for regulatory compliance and patient safety in radiotherapy centers.

Purpose of the Study:

• To design optimal radiation shielding for LINAC rooms in new radiotherapy facilities.
• To reduce effective equivalent dose from LINACs to meet regulatory standards.

Main Methods:

• Shielding calculations performed for 20 MV LINACs following NCRP 151 guidelines.
• Adherence to ALARA principle with dose limits of 0.04 mSv/week (controlled) and 0.002 mSv/week (uncontrolled).
• Comparison of planned optimized LINAC rooms with existing non-optimized designs to assess cost-effectiveness.

Main Results:

• Non-optimized room sizes (610x610 cm²) were found unsuitable for total body irradiation (TBI).
• Optimized room size (762x762 cm²) led to a 15% reduction in shielding costs despite a larger area.
• Re-evaluation of non-optimized rooms with optimized calculations indicated potential shielding cost reductions of up to 41%.

Conclusions:

• Non-optimized LINAC room designs impose financial burdens on hospitals.
• Inadequate room design can compromise the provision of essential patient healthcare facilities.
• Optimized shielding design is essential for both economic efficiency and functional radiotherapy services.