Exposure to radiation is affected by three important factors. Which set correctly lists those factors?

Exposure to radiation is affected by three important factors. Which set correctly lists those factors?

• A. Time, distance, temperature
• B. Time, energy, shielding
• C. Distance, shielding, humidity
• D. Time, distance, shielding

Answer: (D)

Exposure to radiation is determined by three primary factors: how long you are exposed, how far you are from the source, and what material is between you and the source. The distance factor matters because radiation spreads out as it travels; moving farther away reduces the dose rate—roughly, doubling the distance cuts the exposure to about one quarter. Time matters because the total dose you receive is the dose rate multiplied by the time you spend near the source, so shortening exposure directly lowers your accumulated dose. Shielding matters because appropriate barriers absorb or scatter radiation, decreasing the amount that reaches you. Temperature and humidity don’t directly change the amount of radiation you receive, and while the energy of the radiation influences how easily it penetrates materials, the three practical factors emphasized for minimizing exposure are time, distance, and shielding. Therefore, the set that lists Time, Distance, Shielding is the correct one.

Exposure to radiation is determined by three primary factors: how long you are exposed, how far you are from the source, and what material is between you and the source. The distance factor matters because radiation spreads out as it travels; moving farther away reduces the dose rate—roughly, doubling the distance cuts the exposure to about one quarter. Time matters because the total dose you receive is the dose rate multiplied by the time you spend near the source, so shortening exposure directly lowers your accumulated dose. Shielding matters because appropriate barriers absorb or scatter radiation, decreasing the amount that reaches you.

Temperature and humidity don’t directly change the amount of radiation you receive, and while the energy of the radiation influences how easily it penetrates materials, the three practical factors emphasized for minimizing exposure are time, distance, and shielding. Therefore, the set that lists Time, Distance, Shielding is the correct one.