01:2023 Application of dose constraints for shielding of rooms for x-ray imaging

Technical report, Nordic Working Group on Medical Applications


Dose constraints were introduced into the ICRP radiation protection system as a tool to optimise radiation protection. Dose constraints have been adopted in international radiation protection standards as well as the European Radiation Protection Directive necessitating implementation into national legislation in EU countries. In some countries, the concept of dose constraints is included in the legal requirements, for example for structural radiation shielding. Knowledge of the application of dose constraints is important both for the national authorities and for the facilities that apply them. This report concerns the application of dose constraints and more specifically when used in the assessment of shielding for dental intraoral radiography facilities. A lack of consistency in the current recommendations of lead equivalencies was identified and a new joint assessment was performed. The application of dose constraints in the legal framework differs between Nordic countries, some do not apply dose constraints as such but do apply similar concepts. In some cases, dose constraints have been set for the general public and other constraints for workers working in the facilities. This makes it difficult to give common Nordic recommendations on radiation shielding. However, a general framework for the application of dose constraints was derived. Different input parameters used for shielding calculations and how these affected the need for shielding for dental intraoral radiography facilities were also studied.