For mobile X-ray units, can the exposure switch be the dead-man type?

• A. NEVER ALLOWED
• B. YES
• C. ONLY UNDER SUPERVISOR
• D. NO

Answer: (B)

On mobile X-ray units, using a dead-man exposure switch is allowed and commonly used. A dead-man switch requires continuous pressure from the radiographer to keep the exposure active; if the operator lets go, the exposure stops immediately. This design ensures the radiographer remains in direct control throughout the shot, enhances safety for the patient and staff, and provides an immediate fail-safe if the patient moves or if the operator needs to stop the procedure quickly. Other options suggesting it’s never allowed or only under supervisor don’t fit safety practice, because keeping the operator in direct, active control during exposure is a fundamental protection.