Radiation surveillance during cyclotron commissioning and pilot-scale FDG production at the Institute of Nuclear Medical Physics.

Abstract

The commissioning of medical cyclotrons necessitates a thorough assessment of radioactive waste management systems, operational protocols, and radiological safety. Significant neutron and gamma radiation is generated during cyclotron operation for radionuclide production, which are frequently employed in positron emission tomography (PET) for clinical diagnosis and biological research. This study assesses waste management procedures and radiation risks at the Institute of Nuclear Medical Physics' recently commissioned cyclotron facility. Neutron and gamma dose rates were measured at multiple locations under single-beam (80 μA) and dual-beam (160 μA) operational modes. Calibrated radiation survey meters were used to obtain reliable dose measurements during routine cyclotron operation. While gaseous radionuclides were temporarily housed in the air compression station (ACS) prior to controlled emission through the ventilation stack, liquid radioactive waste was kept in lead-shielded decay tanks to allow controlled radioactive decay prior to disposal. Gamma radiation and stack airflow were continuously monitored to guarantee adherence to workplace safety regulations. Neutron and gamma dose rates within the cyclotron vault increased with beam current, ranging from 45.7 ± 4.2 to 49.0 ± 4.5 mSv h-1 and 50.24 ± 2.56 to 95.51 ± 4.87 mSv h-1, respectively. Effective shielding had been verified by the extremely low radiation levels (≤0.7 μSv h-1) at the vault entrance, console room, and nearby locations. The findings demonstrate that the GE PETtrace Cyclotron facility operates reliably under both single-beam and dual-beam configurations, thereby ensuring robust radiological protection for personnel and the surrounding environment.