in terms of materials, encapsulation, and safety testing. Unsealed sources are exploited in contexts such as radioactive tracers in chemical, biological, or physical systems to monitor evolution and processes. Description of Sealed and Unsealed Sources Radiological Quantities (units and quantities): Radiological quantities are essential for radioprotection, as they allow us to quantify exposure to ionizing radiation, assessing risks and ensuring the safety of people and environments. Let's explore each of the main concepts and units mentioned in more detail: