Radiation Levels Measurement at Workplace of Cyclotron-PET/CT Facilities in Karachi using TLD Dosimeters.

A ‘Cyclotron’ is a proton particle accelerator, broadly used for short-lived isotopes (like F-18) production for imaging in radiation oncology. In Pakistan, Fluorine (F-18) is being produced by the cyclotrons installed in various hospitals. F-18 emits two gamma photons through the annihilation phenomenon, having 511 keV energy each. F-18 has converted into (18F) Fluorodeoxyglucose (FDG) through the synthesis process. This high-intensity gamma photon may be dangerous to radiation workers if radiation safety regulations are not followed. A study was conducted for the measurement of ambient radiation levels in the controlled areas and supervised areas of cyclotron facilities using Thermoluminescent Dosimeters (TLDs). The results obtained from TLDs were formulated and evaluated. All measured values were meeting the criteria of classification of areas i.e., the radiation doses will receive greater than 6mSv/year in a Controlled area and the radiation dose will receive greater than 1mSv/year in a Supervised area as mentioned in Pakistan Nuclear Regulatory Authority (PNRA’s) Regulations on Radiation Protection (PAK/904). It is concluded that all workers received radiation doses within limits and the facilities had implemented clause 26 of PNRA Regulations through effective shielding in the design of the cyclotron facilities, and dose monitoring. The effective implementation of PNRA regulations is verified through regulatory oversight and through such type of cross-verification in the country. [ABSTRACT FROM AUTHOR]