Minimum source-to-skin distance for mobile radiography must be:

Minimum source-to-skin distance for mobile radiography must be:

• A. 15 inches
• B. 12 inches
• C. 36 inches
• D. 55 inches

Answer: (A)

Maintaining a minimum source-to-skin distance in mobile radiography is about limiting the dose delivered to the patient’s skin while allowing for safe positioning and shielding. The minimum distance of 15 inches helps reduce skin exposure through the inverse-square relationship between distance and beam intensity, while still giving enough clearance for proper tube placement and protective measures. Distances much shorter than this would increase skin dose, and distances much longer would make it difficult to achieve a usable image and would complicate handling and shielding on a portable system. Hence, 15 inches represents the safe, practical lower bound used in this context.

Maintaining a minimum source-to-skin distance in mobile radiography is about limiting the dose delivered to the patient’s skin while allowing for safe positioning and shielding. The minimum distance of 15 inches helps reduce skin exposure through the inverse-square relationship between distance and beam intensity, while still giving enough clearance for proper tube placement and protective measures. Distances much shorter than this would increase skin dose, and distances much longer would make it difficult to achieve a usable image and would complicate handling and shielding on a portable system. Hence, 15 inches represents the safe, practical lower bound used in this context.