Shielding: Using materials to absorb radiation before it reaches the body. Lead is effective for gamma rays, while a few centimeters of air or a sheet of paper can stop alpha particles.
Distance: Increasing the distance from a source significantly reduces exposure due to the Inverse Square Law, where the intensity of radiation is inversely proportional to the square of the distance ().
Time: Minimizing the duration of exposure directly reduces the total dose received by the individual.
Protective Clothing: For contamination risks, wearing suits, gloves, and masks prevents radioactive dust or liquids from touching the skin or being inhaled/ingested.
Alpha Radiation: Externally, it is the least dangerous as it cannot penetrate the dead layer of skin. Internally (via inhalation or ingestion), it is the most dangerous because it is highly ionizing and causes intense localized damage to living cells.
Beta Radiation: It can penetrate skin to a depth of a few millimeters, making it a moderate hazard both externally (skin burns) and internally.
Gamma Radiation: It is highly penetrating and can pass through the body easily. It is primarily an external hazard because it can reach internal organs from a distance, though it is less ionizing than alpha or beta.
Identify the Source: Always check if the question describes a source at a distance (irradiation) or a substance that has been spilled, breathed in, or swallowed (contamination).
Internal vs. External: Remember that the 'most dangerous' type of radiation changes depending on whether the hazard is internal or external. Alpha is the 'internal villain' but the 'external weakling'.
Safety Logic: When asked how to handle a source, prioritize 'Distance' and 'Shielding' (e.g., using long-handled tongs and lead-lined boxes). When asked how to prevent contamination, prioritize 'Containment' (e.g., wearing gloves and masks).
