SU-E-T-266: Shielding Measurements for a Proton Therapy Facility.

Area of Science:

• Medical Physics
• Radiation Oncology
• Health Physics

Background:

• Proton therapy centers require precise radiation dose calculations for safety.
• Analytical methods offer a way to predict radiation levels.
• Previous work by Avery, et al. established analytical calculations for the Roberts Proton Therapy Center.

Purpose of the Study:

• To empirically validate the precision of analytical radiation dose calculations.
• To compare predicted doses with measured doses at specific points within a proton therapy facility.

Main Methods:

• Neutrak dosimeters were deployed at key locations within the facility.
• Dose measurements were collected over one to two months.
• Measured doses were compared against analytical predictions from Avery, et al.

Main Results:

• Two measurement points demonstrated less than 10% deviation from calculated doses.
• Points shielded by concrete and pre-cast blocks showed lower precision.
• Areas shielded by concrete and the facility's cyclotron also exhibited reduced precision.

Conclusions:

• The analytical method is precise for predicting doses behind concrete shielding.
• Further investigation is needed for shielding composed of materials other than concrete, such as cyclotron components.
• Follow-up calculations using the same analytical method are recommended for complex shielding scenarios.