What happens to the effective dose to the radiographer if the distance between the x-ray source and radiographer increases, assuming all other factors remain constant?

What happens to the effective dose to the radiographer if the distance between the x-ray source and radiographer increases, assuming all other factors remain constant?

• A. Decrease
• B. Increase
• C. Remain unchanged
• D. Cannot be determined

Answer: (A)

Distance governs how much radiation reaches a person because of the inverse square law. In radiography, the dose rate from the x-ray source falls off with the square of the distance, so moving farther away reduces the dose to the radiographer. Doubling the distance cuts the dose to one quarter, tripling reduces it to one ninth, and so on. With all other factors kept constant, increasing the distance therefore decreases the effective dose that the radiographer receives.

Distance governs how much radiation reaches a person because of the inverse square law. In radiography, the dose rate from the x-ray source falls off with the square of the distance, so moving farther away reduces the dose to the radiographer. Doubling the distance cuts the dose to one quarter, tripling reduces it to one ninth, and so on. With all other factors kept constant, increasing the distance therefore decreases the effective dose that the radiographer receives.