To ensure consistency of radiographic quality from one exposure to the next, what device may be used?

• A. Electronic timer
• B. Automatic collimation
• C. Automatic exposure control
• D. Falling load generator

Answer: (C)

Consistent radiographic quality is achieved by automatically regulating the exposure so the image receptor receives the same amount of radiation each time. Automatic Exposure Control does this by using detectors under the patient to monitor the x‑ray exposure in real time. When the detectors reach the pre-set exposure level, the system automatically terminates the exposure. This feedback mechanism accounts for variations in patient size, position, and tissue density, helping produce uniform image density across exams.

Without this control, a technician would have to guess the exposure time or factors, which leads to variable density and more repeats. Other options don’t adjust exposure based on the actual amount reaching the detector: a timer only times the exposure; automatic collimation changes beam size; and a falling-load generator optimizes generator performance but doesn’t directly ensure consistent IR exposure from one exposure to the next.