Which tool is commonly used to locate voids or air pockets in a collapsed structure?

Which tool is commonly used to locate voids or air pockets in a collapsed structure?

• A. Thermal imaging camera only.
• B. Standard stethoscope for field use.
• C. Acoustic listening devices (listening tools) or search cameras.
• D. Infrared markers placed on walls.

Answer: (C)

When searching a collapsed structure, you need tools that can both sense what’s inside the rubble and let you see into tight spaces. Acoustic listening devices and search cameras fit that need perfectly. Acoustic listening tools use sensitive microphones and sensors to pick up faint sounds through dense material—breathing, shifting rubble, or movement—that point to a possible void or pocket where a victim could be located. Search cameras, on the other hand, can be threaded into cracks or small openings to provide a visual look inside those spaces, confirming the presence of a void and showing you the interior layout to guide your next steps.

Other options don’t align as well with locating hidden spaces: thermal imaging can miss voids once dust and debris obstruct heat signatures, stethoscope-type devices aren’t practical for field rubble conditions and lack the range needed, and infrared markers on walls don’t help uncover hidden cavities at all.