Which of the following basic principles can be used to reduce radiation dose?

• A. Time
• B. Distance
• C. Shielding
• D. All of the above

Answer: (D)

Reducing radiation dose relies on three protective strategies: limit exposure time, maximize distance from the source, and use shielding. Shorter exposure times directly reduce the amount of radiation delivered and also help avoid repeats. Increasing distance from the source leverages the inverse square effect: doubling the distance reduces dose to roughly one quarter, so staying back or using remote controls makes a big difference. Shielding physically blocks or attenuates photons, so protective barriers and personal shielding absorb energy and lower the dose to exposed tissues. Because each approach lowers dose, using all three provides the greatest protection, making using all of these strategies the best choice.