In CT with radiation, which statement best describes occupational exposure?

In CT with radiation, which statement best describes occupational exposure?

• A. Low occupational doses; collimated beam; only secondary radiation in the room
• B. High occupational doses; uncollimated beam; primary radiation in the room
• C. Moderate occupational doses; wide beam; primary radiation leakage
• D. No occupational exposure due to shielding

Answer: (A)

In CT, the main thing affecting how much staff are exposed to radiation is the source of that exposure. The useful or primary beam is shaped by collimation to stay within the patient, and protective shielding and barriers prevent it from reaching the room and its occupants. As a result, occupational exposure comes mainly from secondary radiation—scatter from the patient and any leakage from the x-ray tube—which is why the dose to personnel is typically low when proper shielding and collimation are used. The description that matches this reality states that occupational doses are low, the beam is collimated, and only secondary radiation is present in the room. Descriptions that imply exposure to the primary beam in the room, wide or uncollimated beams, or the idea that shielding eliminates all exposure do not reflect how CT setups actually protect operators.

In CT, the main thing affecting how much staff are exposed to radiation is the source of that exposure. The useful or primary beam is shaped by collimation to stay within the patient, and protective shielding and barriers prevent it from reaching the room and its occupants. As a result, occupational exposure comes mainly from secondary radiation—scatter from the patient and any leakage from the x-ray tube—which is why the dose to personnel is typically low when proper shielding and collimation are used. The description that matches this reality states that occupational doses are low, the beam is collimated, and only secondary radiation is present in the room. Descriptions that imply exposure to the primary beam in the room, wide or uncollimated beams, or the idea that shielding eliminates all exposure do not reflect how CT setups actually protect operators.