Why is beam alignment checked during QA?

• A. To verify receptor color quality.
• B. To check the room lighting level.
• C. To ensure the X-ray beam is directed correctly relative to the receptor and patient; it reduces distortion.
• D. To measure the darkness of the viewing monitor.

Answer: (C)

Beam alignment in QA is about getting the exposure geometry right. When the X-ray beam is directed so it is properly centered and perpendicular to the image receptor and aligned with the patient, the resulting image shows the correct size, shape, and positioning of structures with minimal distortion. Proper alignment also helps ensure the entire area of interest is captured without edge cutoffs and supports consistent imaging across exams, which reduces repeats and patient dose. If the beam is off-target or tilted, structures can appear distorted or magnified incorrectly, and important details may be missed.

Receptor color quality, room lighting, and monitor darkness affect viewing or detector performance or ambient conditions, not the actual geometric alignment of the beam, so they aren’t the reason beam alignment is checked.