Inverted-Cone Pattern
Definition
A fire pattern with the apex at ceiling level and widening toward the floor, associated with fast-developing fires, flashover conditions, or ceiling-level ignition; unreliable for origin determination in post-flashover rooms.
- Shape
- Apex at ceiling, widening toward the floor
- Associated with
- Fast fire development, flashover, ceiling-level ignition
- Reliability
- Unreliable for origin determination post-flashover
Common questions
Why does flashover undermine origin conclusions from this pattern?+
Once a room reaches flashover, the whole compartment burns at high heat flux nearly simultaneously, and the resulting damage can mimic a ceiling-origin pattern regardless of where the fire actually started.
How does it differ from a classic V-pattern?+
A V-pattern narrows upward from a discrete origin low on a wall, while an inverted-cone widens downward from the ceiling, a geometry tied to a fire-development stage rather than a single point origin.
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