Assessment of the structural shielding integrity of some selected computed tomography facilities in the Greater Accra Region of Ghana

The structural shielding integrity was assessed for four of the CT facilities at Trust Hospital, Korle-Bu Teaching Hospital, the 37 Military Hospital and Medical Imaging Ghana Ltd. in the Greater Accra Region of Ghana. From the shielding calculations, the concrete wall thickness computed are 120, 145, 140 and 155mm, for Medical Imaging Ghana Ltd. 37 Military, Trust Hospital and Korle-Bu Teaching Hospital respectively using Default DLP values. The wall thickness using Derived DLP values are 110, 110, 120 and 168mm for Medical Imaging Ghana Ltd, 37 Military Hospital, Trust Hospital and Korle-Bu Teaching Hospital respectively. These values are within the accepted standard concrete thickness of 102- 152mm prescribed by the National Council of Radiological Protection and measurement. The ultrasonic pulse testing indicated that all the sandcrete walls are of good quality and free of voids since pulse velocities estimated were approximately equal to 3.45km/s. an average dose rate measurement for supervised areas is 3.4 μSv/wk and controlled areas is 18.0 μSv/wk. These dose rates were below the acceptable levels of 100 μSv per week for the occupationally exposed and 20 μSv per week for members of the public provided by the ICRU. The results mean that the structural shielding thickness are adequate to protect members of the public and occupationally exposed workers (au).