Which one of the following should be the minimum distance between two items going through the X-BIS ?

The X-ray Baggage Inspection System (X-BIS) is a critical security tool used at airports and high-security installations to scan luggage for prohibited items. According to standard operating procedures and training manuals for security personnel (such as those issued by the Bureau of Civil Aviation Security (BCAS) in India), a minimum distance must be maintained between two items on the conveyor belt to ensure clear imaging and prevent overlapping of X-ray shadows.

The standard prescribed minimum distance between two items going through the X-BIS is 40 cm. This spacing allows the operator sufficient time to analyze the image of each bag individually and ensures that the sensors can correctly trigger the X-ray beam for each distinct object, maintaining the integrity of the screening process.