Which factors can be directly influenced by x-ray personnel during day-to-day use of x-ray equipment?

• A. 1 and 2
• B. 2 and 3
• C. 1, 2, and 3
• D. 1 and 3

Answer: (C)

Technologists directly control three areas that determine both patient dose and image quality: exposure factors, beam restriction, and positioning. Adjusting exposure factors—kVp, mA, and exposure time—decides how many photons and what energy reach the patient, which in turn affects image contrast and radiation dose. Tight beam restriction through collimation (and using filtration and shielding) limits the irradiated tissue, reduces scatter, and lowers patient dose while improving image quality. Proper positioning and centering, along with maintaining appropriate distance, ensure the anatomy of interest is irradiated efficiently; this minimizes repeats and leverages the inverse square law to control dose.

Since each of these three controllable aspects can be adjusted in day-to-day practice, all are factors you can influence, making the option that includes all three the best choice.