Which are the three fundamental principles of radiation protection?

• A. Inverse Square Law, Time, Shielding
• B. Time, Distance, Shielding
• C. Distance, Shielding, Dose Optimization
• D. Time, Shielding, Distance

Answer: (B)

Time, distance, and shielding are the three fundamental principles because they directly control how much radiation can affect you. Reducing the time you spend near the source lowers the total dose since exposure accumulates with time. Increasing your distance from the source makes a big difference because radiation intensity drops rapidly with distance—the farther you are, the less you receive. Shielding adds a barrier that attenuates or absorbs radiation before it reaches you, providing protection even if some exposure time can’t be avoided. These three controls form the core approach to keeping doses as low as reasonably achievable. Other ideas like dose optimization are important, but the three foundational elements are time, distance, and shielding.