Designing out terrorism: human factors issues in airport baggage inspection

All air passenger baggage is screened at airports by means of 2-D X-ray imaging which results in a computer display of each luggage item that is then visually searched by an operator (screener) for the presence of potential threat items (e.g. knifes, guns, improvised explosive devices [IED]). Despite improvements in screener training and available technology (e.g. image enhancement functions, threat image projection, 3-D X-ray imaging) the performance of screeners is variable which leads to the potential for terrorist threat to aircraft and passengers. A new training scheme to improve performance in baggage screening is under development (EPAULETS: Enhanced Perceptual Anti-terrorism Universal Luggage Examination Training System) and some of the initial human factors issues that underlie variable screener performance are considered.