In radiography low-energy x-ray do not contribute to the quality formation of an x-ray image; but instead exposes the body to unwanted radiation. The process of removing this low-energy x-ray from the x-ray beam is known as filtration. Filtrations also increase the average energy (quality) of the x-ray beam. Evaluation of total filtration of xray tube is one of the radiological tests that determine the adequacy of filtration and it also reflects the penetration power of the beam. This research evaluate the Half Value Layer (HVL) of the X-ray in the radiology unit of some Hospitals in Zaria, Kaduna State and determined their homogeneity factor (HF)( whether it is polychromatic or monoenergetic in nature). Series of Aluminum sheets of different thickness in conjunction with ion chambser used to detect and indicate the integrate exposure to be read directly on the internal calibrated scale were used. It was found that some of the hospitals beam homogeneity factors is one (1) while some showed less than one (1). The HVL Aluminum sheet, homogeneity factor for all the hospitals showed little or no variance from the standard recommendations. The calculated first HVL of the hospitals A-E were found to be 0.032, 0.0119, 0.0045, 0.016 and 0.024 respectively. And, the HF 1, 0.98, 1.05, 0.53 and 1 respectively.
