Which combination of features is required for mobile X-ray exposure switches?

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

Answer: (B)

Mobile X-ray exposure controls must keep the operator in charge and provide a quick, reliable shutoff to minimize radiation dose. The first essential element is a dead-man type switch, meaning exposure only occurs while the switch is actively pressed. The second needed safety aspect is a secondary safety feature—such as a separate interlock or a two-step clearance—that prevents accidental reactivation or continuous exposure and ensures a deliberate reset before the next exposure. Together, these two features ensure that exposure starts only when the operator intentionally initiates it and stops immediately when the switch is released or the safety interlock is engaged. Without both elements, there’s a greater risk of unintended exposure or difficulty stopping exposure promptly. That’s why the combination including these two safety features is the best choice.