Structural Shielding Evaluation: A Case Study of the Radiography Room of a Rural Hospital in Jos, Nigeria

Introduction: Most Nigerian rural hospitals constructed before the publication of the 2005 National Council on Radiation Protection and Measurements Report No. 147 did not undergo a performance assessment at the time of construction. To avoid overexposure to ionizing radiation and to ensure adequate protection of patients, workers, and the public, the shielding barriers need to be evaluated to ascertain that they conform to this standard. Methods: This study evaluates the shielding barriers for the general radiography room in a rural hospital in Jos, Nigeria. The workload information, generator voltage waveform, anode material, filtration, and anode angle with XRAYBARR calculation model were used to estimate the thickness of lead, concrete, gypsum, steel, plate glass, and wood required to shield the X-ray facility installed in the hospital. The design dose limit was compared to the estimated shielded dose, and the calculated shielded barrier thickness to the design shielded barrier thickness was also compared. Results: The unshielded radiation doses inside the X-ray room were high, indicating that the radiological department of the study area is not minimizing radiation doses to patients. The calculated doses beyond the barriers were greater than the design dose limit, indicating that the shielded barriers in place were not adequate and did not comply with the international standard. Discussion: Hospitals must understand the type of shielding materials that can provide adequate protection and to what extent they can protect their radiography rooms. Management and radiation protection agencies need to ascertain whether these barriers are still adequate or require reinforcement through regular quality assurance testing. Due to an increase in workload associated with an increase in population and urbanization, proper policies are needed more than ever in this and other rural hospitals in Nigeria. Conclusion: The tested X-ray rooms did not comply with international recommendations for shielding thickness. Except for the door, console, and changing room, a 0.5 mm-thick lead reinforcement is required. It is also recommended that quality assurance testing occur on an annual basis.