ASSESSMENT OF DESIGN AND SHIELDING IN SOME SELECTED CONVENTIONAL X-RAY AND COMPUTED TOMOGRAPHY (CT) FACILITIES IN BURKINA FASO

ABSTRACT The main objective of this work is to assess the integrity of structural shielding to validate the protection of the staff and the public for two selected general radiography and CT facilities. The assessment for general radiography was based on 729 examinations for facility A and 706 examinations for facility B. For computed tomography (CT) rooms, a total of 293 body and 190 head procedures were used for facility A, and 195 body and 160 head procedures for facility B. For general radiography, the workload distribution and the normalized workload per patient have been determined for each room type (floor and chest-bucky). For facility A, the normalized workload per patient was 0.96 mA min patient-1 for the floor and 1.25 mA min patient-1 for the chest-bucky, the unshielded primary air-kerma per patient for the floor was 2.56 mGy patient-1 and 3.4 mGy patient-1 for the chest-bucky in the general radiography room. The average DLP were 1830 610 mGy cm and 859 438 mGy cm for head and body respectively in the CT room. For facility B, the normalized workload per patient was 1.14 mA min patient-1 for the floor and 0.53 mA min patient-1 for the chest-bucky, the unshielded primary air-kerma per patient was 3.13 for the floor and 1.9 for the chest-bucky in general radiography room. The average DLP were 806 346 mGy cm and 305 154 mGy cm for head and body respectively in the CT room. For both of these facilities, the calculated barrier thicknesses are smaller than the existing barrier thicknesses. Dose rate measurements confirmed that the different barriers thicknesses are enough to maintain the dose received by workers and the public below the recommended dose limits.