Characteristics of Controlled Demolition

1. Sudden Onset: In controlled demolition, the onset of the collapse is sudden. One moment, the building is perfectly motionless; the next moment, it suddenly begins to collapse.
2. Straight Down: The building comes straight down, into, or at least close to, its own footprint, so that it does not harm the other buildings.
3. Almost Free-Fall Speed: Collapse at almost free-fall speed. This can occur because the supports for the lower floors are destroyed, so that when the upper floors come down, they encounter no resistance.
4. Total Collapse:The building completely falls to ground level.
5. Sliced Steel: In controlled demolitions of steel-frame buildings, explosives are used to slice the steel columns and beams into pieces.
6. Pulverization of Concrete and Other Materials: Explosives will pulverize concrete and most other non-metallic substances into tiny particles.
7. Dust Clouds: Dust clouds result when explosions eject the dust from the building with great energy.
8. Horizontal Ejections: Horizontal ejection of other materials, besides dust.
9. Demolition Rings: A series of small explosions run rapidly around a building.
10. Sounds Produced by Explosions: The use of explosives to induce collapses produces, of course, sounds caused by the explosions.
11. Molten Steel: If explosives were used to slice the steel columns there would be molten steel in the debris.