What colour light indicates an X-ray machine is on?

What colour light indicates an X-ray machine is on?

• A. Red
• B. Green
• C. Blue
• D. Amber

Answer: (A)

In radiography, the indicator color tells you when the X-ray beam could be emitted, which is a safety-critical cue. A red light means the machine is energized and capable of producing radiation, so exposure could occur and people should be behind shielding or out of the beam path. Red is used because it universally signals danger and grabs attention quickly. Other colors (green, blue, amber) are not standard signals for an active X-ray beam and may indicate other non-exposure statuses, so they don’t reliably warn of potential radiation exposure.

In radiography, the indicator color tells you when the X-ray beam could be emitted, which is a safety-critical cue. A red light means the machine is energized and capable of producing radiation, so exposure could occur and people should be behind shielding or out of the beam path. Red is used because it universally signals danger and grabs attention quickly. Other colors (green, blue, amber) are not standard signals for an active X-ray beam and may indicate other non-exposure statuses, so they don’t reliably warn of potential radiation exposure.