Basics of radioprotection

Abstract

With an increasing use of ionizing radiation in medicine and an increasing variety of radiopharmaceuticals for diagnostic or therapeutic purposes, radiation protection plays an important role in the whole process. The role of radiation protection is to prevent deterministic effects and to limit the probability of stochastic effects to a considered acceptable level. The principles of radiation protection and safety are based on recommendations from ICRP. The detailed formulation of the principles can be found in ICRP publications and they cannot easily be paraphrased without losing their essence. However, a brief, although simplified, summary of the principles is given in this article. In nuclear medicine unsealed radioactive sources are used, so in addition to external irradiation where time, distance and shielding apply, also contamination, inhalation and ingestion must be considered. Collectively the systematic efforts to reduce external and internal radiation exposure are known as the ALARA radiation safety principles. ALARA is an acronym used in radiation safety for “As Low As Reasonably Achievable.” These ALARA principles are applied to the patient, staff, members of public, caregivers and comforters of the patient to minimize the radiation doses and limit the release of radioactive material into the environment by employing all reasonable methods. This article discusses the mentioned groups of people, the routes of irradiation and the optimization of radiation protection. Useful references, important issues of the optimization of nuclear medicine procedures, and diagnostic reference level are also described.