TY JOUR TI Problems of Ensuring Radiation Safety of Personnel when Operating Proton Therapeutic Accelerators Using an Example of the Proton Therapy Center in Dimitrograd KW therapeutic proton accelerators KW high-energy ionizing radiation KW secondary radiation KW radiation safety JO Medical Radiology and radiation safety AU Tsoviyanov, A.G. AU Gantsovskii, P.P. AU Shandala, N.K. AU Shinkarev, S.M. AU Romanov, V.V. PY 2019 IS 64 PB Federal Medical Biological Agency of Russia