The Future of Radiological Protection


Impact of New Developments in the Commissioning of Operational Radiation Protección in Compact Proton Therapy Centers (CPTC)

Author(s): Gonzalo García-Fernández 1, Eduardo Gallego 1, José M Gómez-Ros 2, Héctor R Vega-Carrillo 3, Karen A. Guzmán-García 3, Lenin E. Cevallos-Robalino 4, Marisa Ogando 5, Alejandro Carabe-Fernández 6, Alejandro Bertolet-Reina 7
( 1 Universidad Politécnica de Madrid, Spain; 2 Ciemat, Spain; 3 Universidad Autónoma de Zacatecas, México; 4 Universidad Politécnica Salesiana, Ecuador; 5 Bioterra, SL, Spain; 6 Hampton University Proton Therapy Institute, United States; 7 Massachusetts General Hospital, United States)



Proton therapy is in continuous ever evolving to improve its performance. Some prominent current trends involve cutting-edge delivery methods or building compact proton centers. New developments have a direct impact in radiation protection of proton facilities and actions should be developed continuously with the aim that new centers meet all the requirements. The study of radiological protection in multi-room centers has been widely studied elsewhere, however, compact centers have specific features that pose a challenge in radiation protection, and the present work suggest different contributions to the body of knowledge in these compact facilities. Compact Proton Therapy Centers (CPTC) act out latest advances in particles: Usually have one single room, small footprint and a standard configuration, higher radiation density (Sv/m2), using the most advanced equipment and machinery to reduce their size, the delivery mode of protons is Pencil Beam Scanning (PBS), and there is a mix of professional exposed workers (clinical and technical staff) in these centers.

The present work is framed into the project Contributions to operational radiation protection and neutron dosimetry in compact proton therapy centers (CPTC), which is focused on assessing the impact of these innovations on the operational radiation protection and commissioning of the compact facilities. Thus, several tasks have been carried out over the last three years, as checking and evaluation of shielding, comparing ambient dose equivalent of several CPTC, analyzing activation with different types of concrete, and activation in machinery, air and water of the facility, characterizing wide range rem-meters and neutron area monitors to measure neutron fields, studying new proton delivery techniques and their neutron fields, or assessing personal dosemeters, among others. The aim of the work is to present outcomes achieved in the aforementioned areas. As a result, a commissioning process of the operational radiation protection in compact centers will be suggested, lined up with the requirements by the Spanish Regulatory Body.

Considering topics as new methods of application of dose in development (proton arc therapy, flash-therapy with protons), new materials for barriers and shielding or recent radiation monitoring equipment, future works must be carried out to study their impact on operational radiation protection and recommendations such as ICRP Publication 127, Radiological Protection in Ion Beam Radiotherapy, should be updated periodically taking into account the new methods and technologies developed.

Keywords: Compact proton therapy centers (CPTC); Proton new delivery modes; Operational radiation protection; ICRP Publication 127