Development and Application of Diagnostic Reference Levels for Adult Patients in Diagnostic Radiology

Radiation protection of patients is based on the principles of justification and optimization. The principle of optimization, the most important and effective one, relies on the system of diagnostic reference levels (DRLs) that have been successfully used in global practice and are officially introduced in Basic Sanitary Rules for Radiation Safety-99/2010. The guidelines establish diagnostic reference levels for adult X ray imaging in medical settings and determine their application to balance radiation protection of patients and the provision of high-quality diagnostic information. The guidelines relate to medical X-ray diagnostic and radiological examinations and are intended for the staff and management of medical facilities, agencies that are responsible for radiation control in medical facilities, and can also be used by expert institutions and agencies for health security and disease control. The guidelines consider and compare various methods to determine the DRLs based on measured and/or calculated dosimetric parameters, such as the dose-area product, entrance dose, mean glandular dose, activity, and effective dose. Furthermore, they propose a scheme to determine the standard dose values depending on the type of X-ray diagnostic device used; present the steps to apply the DRLs in practice; establish measures in case the standard doses exceed the DRLs; and define the levels to perform optimization.