Char Depth Gradient
Definition
The depth of charred wood measured at multiple points; deeper char means longer exposure, so the gradient reveals the direction of fire travel.
- Measured across
- Multiple points on charred wood
- Relationship
- Deeper char = longer exposure
- Reveals
- Direction of fire travel
- Field tool
- Char-depth probe
Common questions
How does a gradient differ from a single char-depth reading?+
One reading only tells you how long that specific spot burned, while a gradient across several points lets an investigator compare relative exposure times and infer which direction the fire was moving as it progressed through the structure.
Can char depth alone reliably fix fire duration?+
Not precisely on its own, because char rate depends on wood species, ventilation, and fuel load, so investigators treat char depth readings as comparative and directional evidence rather than an exact clock of burn time.
Related terms
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