Which practice most effectively reduces exposure to radiation?

• A. Increase time near the source
• B. Move away from the source
• C. Increase shielding thickness
• D. Wear a different dosimeter

Answer: (B)

Distance from the source reduces exposure most effectively, because the dose rate falls off rapidly as you increase distance (the inverse square law). Doubling your distance cuts the exposure to about one quarter, so stepping back or using remote handling dramatically lowers what you receive. Shielding can help, but its impact depends on the material and thickness and isn’t as universally powerful as simply putting more space between you and the source. Increasing time near the source increases dose, so that choice would raise exposure. Wearing a different dosimeter doesn’t change how much radiation you actually receive; it only changes what is recorded. In practice, moving away from the source is the best way to minimize exposure.