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Item EFFECTIVENESS OF THE SHIELDING MECHANISM IN ROOMS HOUSING X-RAY DIAGNOSTIC EQUIPMENTS :A CASE STUDY OF MULAGO HOSPITAL, UGANDA(International Journal of Innovative Research in Advanced Engineering (IJIRAE), 2018-02-02) Festo Kiragga; Kisolo Akisophel; Nakatudde RebeccaThe effectiveness of the shielding against ionizing radiation in controlled and supervised areas of four (4) selected imaging rooms of Mulago hospital was determined. Scattered radiation transmitted to the operator’s console, leakage through the walls and doors to the patient waiting areas was also determined. The effective doses to occupational workers were also determined. The availability and effectiveness of the lead aprons and other protective gears was also investigated. Thermoluminiscent Dosimeters (TLDs) were installed at selected points for a period of four (4) weeks. Radiation leakages to the members of the public were measured using a survey meter, scattered X-ray radiation to staff was measured using TLD badges. The mean scattered radiation in the imaging rooms varied from 1.19 mSv/month in the Computed Tomography (CT) room to 0.38 mSv/month from the Casualty Center (CC). The effective doses to occupational staff were highest in Room 4 (R4) (plain radiography) of 6.8 mSv/yr and lowest in CC at 1.4 mSv/yr. Radiation leakages through selected doors were found to be 18.1 mSv/hr at the Uganda Cancer Institute (UCI). Though there was some leakage, the available shielding was found to be generally effective.Item Calibration of Various Detectors for Commissioning of Total Body Irradiation for a New Installation in Maggiore Hospital, Trieste-Italy(FAMPO : Federation of African Medical Physics organizations, 2023-07-30) Festo Kiragga 1, Rosella Vidimari 2Calibration of detectors: Gafchromic EBT3(GAF) and Metal Oxide Semiconductor Field Effect Transistors (MOSFETs) was done under reference conditions for use in Total Body Irradiation (TBI) conditions. Three Source Axis Distances (SAD) were chosen: 5m, 4.5 m, and 4m with minimal or no backscatter from the wall. Lateral-Lateral (LL), gantry angle 90o, collimator angle 0o, and 6 MV energy were chosen with respect to the nature of the bunker. Percentage Depth Doses (PDDs) were evaluated, first with a big water phantom using calibrated dosimetry diode, P and then also with RW3 slab phantom (30 x 30 x 30 cm3) at the three positions using GAF. Afterwards, the PDDs were then compared allowing the beam to be characterized in different setups. MOSFETs calibration factors corresponding to each channel were also obtained by first measuring the average dose with a Farmer chamber under reference conditions in the same position. Then the MOSFETs were cross-calibrated against the Farmer chamber. A length of 140 cm (pediatric) was found to be in the flatness region with a dose variation of 3%. GAF, and MOSFETs were calibrated and a calibration curve was plotted for GAF while a table of calibration factors was made for the MOSFETs to be used in TBI conditions. A dose variation of less than 2% was achieved between the Farmer chamber and GAF readings at similar points in the RW3 phantom. The beam characteristics were important parameters to understand the behavior of the beam in non-reference conditions (TBI conditions). These were within the tolerance range as dose variations of up to ± 10% are allowed in TBI conditions. The doses measured with the calibrated Farmer chamber and GAF were compared with less than 2% difference and this meant that the GAF can be used in any TBI setup. Therefore, the bunker was found fit for carrying out the TBI technique, particularly for pediatrics.