S-190 Questions and Correct Answers
Origin Ans: The area where the fire started. It is also the point
from which the fire spreads, depending on the fuels present and
the effects of the wind slope.
Head Ans: - The part of a wildland fire with the greatest forward
rate of spread (ROS).
- The head of the fire often burns intensely and may move with
alarming speed.
Fingers Ans: Long, narrow strips of fire that extend from the
main body of a fire.
They form:
-When a fire burns into mixed fuels; slowing in heavy fuel, but
spreading quickly in light fuels
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-Due to variations in terrain or wind direction
-When the head is split by natural features such as fields, water, or
rock outcroppings
Pocket Ans: The unburned area between the main fire and any
fingers.
Perimeter Ans: The outer boundary- or the distance around the
outside edge. Also commonly called the fire edge.
Rear Ans: Also known as the heel of the wildland fire is the end
opposite of the head. The back of the fire. Relatively closer to the
origin of the fire.
Flanks Ans: The sides of a wildland fire, roughly parallel to the
main direction of fire spread. Flanks are identified as either left or
right as you are looking from the heel of a fire toward the head.
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Islands Ans: Unburned areas inside the fire perimeter. Because
they are unburned potential fuels, patrol them frequently and
check for spot fires.
Spot Fire Ans: Fire ignited outside the perimeter of the main fire
by a firebrand.
Slopover Ans: Fire edge that crosses a control line. Also called
Breakover.
Green Ans: Area that is not burnt.
Black Ans: The burn area
Rate of Spread (ROS) Ans: - How fast the fire is moving. Measured
in chains or acres per hour.
- 1 ft. (0.3M)/minute = 1 chain/hour
- 10ft.(3m)/minute = 10 chains/hour
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Flaming Front Ans: Also known as "Fire Front" is the part of the
fire within which continuous flaming combustion is taking place.
The leading edge of the fire perimeter.
Smoldering FIre Ans: Is one that burns without flame and is
barely spreading
Creeping Fire Ans: Burns with a low flame and spreads slowly
Running Fire Ans: Fire spreading rapidly with a well defined head
Backing Fire Ans: Fire that moves away from the head, downhill
or against the wind.
Crowning Ans: When the fire advances across the tops of trees or
shrubs more or less independent of the surface fire
Blowup Ans: - When there is a sudden increase in ROS sufficient
to prevent or rule out direct control of the fire.
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