Which safety practices protect people from external ionizing radiation hazards?

• A. Personal Protective Equipment Only
• B. Time, Distance, and Shielding
• C. Vaccination Programs
• D. Regular Hand Washing

Answer: (B)

External ionizing radiation safety relies on three practical controls: reducing exposure time, increasing distance from the source, and using shielding. Spending less time near the source cuts the total dose since exposure accumulates with time. Moving away from the source significantly lowers dose due to the inverse-square relationship between distance and radiation intensity—the farther you are, the less exposure you receive. Shielding provides a barrier that attenuates or blocks the radiation before it reaches the body, further reducing dose. Personal protective equipment alone isn’t sufficient for external exposure, and vaccination or regular hand washing do not address ionizing radiation hazards. Thus, Time, Distance, and Shielding together offer the most effective protection.