Dose Measurements at Provision Proton Therapy Center

Proton therapy is an advanced method for treating cancerous tumors, and its adoption has expanded significantly in recent years. The production of high-energy protons, however, may result in the creation of secondary neutrons and gamma rays. Hence, ensuring radiation safety at proton therapy centers is crucial, with shielding playing a vital role. This study aimed to evaluate the efficacy of the shielding implemented at the Provision Proton Therapy center in Knoxville, TN, USA. For this purpose, we measured and compared gamma ray radiation levels within the treatment room and the facility's roof. These measurements were conducted using a NaI(Tl) scintillator detector. The PHITS Monte Carlo code was used to deconvolute the incident spectrum using detector response functions. Findings reveal that the facility's shielding effectively protects the general public from gamma ray radiation, with the effective dose within the treatment room being minimal and dose on the roof was comparable to background radiation levels. However, it is important to note that this study did not address the issue of secondary neutron radiation field, which is an important aspect of dose and radiation safety in proton therapy centers.