<![CDATA[A study has been conducted to determine the effect of patient table on the absorbed dose on the Co-60 NPIC-GWXJ80 machine at the Radiotherapy Installation Sanglah Hospital, Denpasar. Measurement of radiation dose is one part of the Quality Control (QC) radiotherapy machine. Measurements were carried out according to the TRS 398 IAEA protocol, using a phantom slab with a thickness 10 cm, dose 200 cGy, Source to Surface Distance (SSD) 80 cm with irradiation angles of 00 (anteroposterior position/AP) and 1800 (posteroanterior position/PA). The calculation of the absorbed radiation dose was carried out using Microsoft Excel worksheet TRS 398. The measurement results showed that the absorbed dose with the installation of the patient table was smaller than without the installation of the patient table. The deviation of the absorbed dose in the measurement of AP, PA without a table and PA with a table, respectively, is 1.24%, 1.48% and 5.04%. The deviation of the absorbed dose in the PA measurement with the table exceeds the tolerance limit set by the IAEA, which is ±5%, so it is necessary to calculate the correction factor for the patient table. The value of the patient table correction factor was 0.97 with the corrected irradiation time is1.56 minutes. The deviation of the absorbed dose based on the results of measurements and calculations using a corrected irradiation time is 2.35%, so that the output of the Co-60 machine is in accordance with the IAEA TRS 398 standard and is suitable for use.]]>
