Name three common collapse patterns you should recognize during structural SAR.

• A. T-topple, inverted pyramid, and cone collapse
• B. Split collapse, wedge collapse, column shift
• C. V-shaped collapse, pancake collapse, and lean-to/umbrella collapse.
• D. Spiral collapse, dome collapse, arch collapse

Answer: (C)

Recognizing how collapse shapes form helps you predict debris movement, identify potential voids, and plan safe access during structure SAR. V-shaped collapse occurs when the upper portion gives way and walls spread outward, producing two debris legs that form a V. This pattern often points to a central location where a void or survivor could be trapped near the apex and suggests careful probing between the legs. Pancake collapse happens when floors fail and settle almost flat, creating a stacked, slab-like debris configuration; it usually results in multiple levels with limited vertical room, so anticipate potential entrapment between floors and watch for secondary collapse between layers. Lean-to or umbrella collapse describes a scenario where one side remains supported while the opposite side drops away, causing a sloping, canopy-like debris over the intact edge; this implies hazards from overhangs and a possible path beneath the supported side, but with risk of sudden shifts if the remaining supports fail. These patterns are the most commonly observed in structural SAR, giving practical cues for locating victims and maintaining safety.