TSO X-Ray Image Interpretation 2 — Questions and Answers
Question 1: On an X-ray image, organic materials such as food and plastic typically appear in which color?
- Orange or amber (Correct answer)
- Blue or green
- Black
- White
Correct answer: Orange or amber
Organic materials have low atomic density and appear orange or amber on standard X-ray color displays.
Question 2: A bag shows a dense, irregularly shaped white mass surrounded by wiring. What is the MOST appropriate first action?
- Alarm the lane and call for a supervisor or EOD (Correct answer)
- Pass the bag through a second time
- Ask the passenger what is inside
- Clear the bag and note it for post-screening review
Correct answer: Alarm the lane and call for a supervisor or EOD
A dense mass with associated wiring is an IED indicator requiring immediate escalation to a supervisor or explosive ordnance disposal team.
Question 3: Which X-ray feature best helps distinguish a firearm from similarly shaped metal objects?
- The characteristic shape including barrel, trigger guard, and grip outline (Correct answer)
- The overall weight of the bag
- The color of the object on screen
- The position of the object within the bag
Correct answer: The characteristic shape including barrel, trigger guard, and grip outline
Firearms have distinctive outlines—barrel, trigger guard, and grip—that remain recognizable even at different orientations.
Question 4: What does the term 'superimposition' mean in the context of X-ray image interpretation?
- Multiple items overlapping, making individual objects harder to identify (Correct answer)
- An image taken from two different angles simultaneously
- The automatic enhancement of bright areas by the X-ray machine
- A deliberate concealment technique using lead-lined bags
Correct answer: Multiple items overlapping, making individual objects harder to identify
Superimposition occurs when objects stack on top of each other in the image, obscuring details and making threat identification more difficult.
Question 5: A TSO notices a laptop-sized object that displays as a solid, uniformly dark rectangle with no internal components visible. This should raise suspicion because:
- Legitimate laptops show complex internal components such as batteries and circuit boards (Correct answer)
- Dark objects always indicate explosives
- Laptops are prohibited in carry-on baggage
- Uniformly colored objects cannot be X-rayed accurately
Correct answer: Legitimate laptops show complex internal components such as batteries and circuit boards
A genuine laptop displays internal structures; a featureless dense block may indicate a concealed threat or modified device.
Question 6: Which of the following best describes the purpose of using the 'organic stripping' or color-inversion function on an X-ray machine?
- To remove organic material colors from the image and highlight inorganic or metallic items (Correct answer)
- To increase the brightness of the entire image
- To detect liquids hidden in clothing
- To print a hard copy of the image for record-keeping
Correct answer: To remove organic material colors from the image and highlight inorganic or metallic items
Organic stripping suppresses the orange organic layer, making it easier to spot metallic or inorganic threat items beneath organic clutter.
Question 7: When an X-ray image shows thin, flat rectangular metal sheets stacked together inside a bag, a TSO should consider the possibility of:
- Sheet explosives such as PETN-based flex explosive concealed within innocent-looking items (Correct answer)
- Standard aluminum food packaging
- A set of metal rulers or straightedges
- Currency wrapped in foil
Correct answer: Sheet explosives such as PETN-based flex explosive concealed within innocent-looking items
Sheet explosives like PETN flex can appear as flat, dense metallic layers and require additional screening.
