ABSTRACT
The success of radiotherapy treatment is the joint responsibility of the radiation oncology team, which comprises professionals from various disciplines such as radiation oncology, medical physics, medical dosimetry, and X-ray treatment technology. Considering the very high dose rates being delivered by the treatment delivery equipment (TDE) compared to the diagnostic X-ray machines, there is great potential for overexposure to the patients or staff, and also to the general public, if proper safety and quality audit (QA) procedures are not adopted, or if the regulatory requirements in radiotherapy are not adhered to. The external beam therapy equipment containing one or more sources (e.g., teletherapy equipment, ViewRay MRI-guided cobalt radiotherapy system, GK system) must display a permanent 'radiation present' sign indicating the existence of radioactive material. For radioisotope machines, the leakage characteristics are different in machine ON and OFF conditions because the source positions are different for the two conditions, for a telecobalt head.
