Measuring visual abilities and visual knowledge of aviation security screeners

Abstract- A central aspect of airport security is reliable detection of forbidden objects in passenger bags using X-ray screening equipment. Human recognition involves visual processing of the X-ray image and matching items with object representations stored in visual memory. Thus, without knowing which objects are forbidden and what they look like, prohibited items are difficult to recognize (aspect of visual knowledge). In order to measure whether a screener has acquired the necessary visual knowledge, we have applied the prohibited items test (PIT). This test contains different forbidden items according to international prohibited items lists. The items are placed in X-ray images of passenger bags so that the object shapes can be seen relatively well. Since all images can be inspected for 10 seconds, failing to recognize a threat ite