Chapter 17 Flashcards
(24 cards)
Wildland fires are
most often starts by lightning
Wildland fires are affected by
the rate of fire spread and fire intensity
Rate of fire spread
is dynamic and complex. Fire spread is affected by
types of fuel burning
the slope or aspect at which the fire is burning
water conditions
Fire intensity
describes how hot a fire is burning.
Forest fire
occurs in area containing heavy fuels and higher levels of vegation such as timbers
Brush fire
occurs primarily in mid level vegetation
Groundcover fire
fire primarily involves low level vegetation ( grasses and other light fuels)
Fire in high level vegetation may
initially burn relatively slowly, they produce much more heat than the other two types of wildland fires.
Forest fires: Information should include the areas
Wind speed and directions
Air temperature and probable or expected changes
Humidity
Approaching or expected weather fronts or conditions
Crown fires
fire works it way up to and rapidly spread across the treetops
Timbers
is another high level vegetation fire hazard
Snag
Trees that have fallen but are hung up in other trees
(Brush fires) mid-level vegetation fires
grow and travel faster but the do no generate the high temps that forest fires do.
Brush fires also tend to occur in
more closely to wildland urban interface areas
The primary hazard of brush fire
is the weather
The next hazard of brush fire
is fire spread
Every fire fighter must be aware of and understand how the weather affects the firefighting effort at brush fire
Wind speed and direction
temperature
Humidity
Expected weather changes
Groundcover fires are the
Fastes growing and moving type of wild land fire, but they produce the least amount of heat.
Every fire fighter must consider the area’s in ground cover fire
Weather conditions Fire spread Extinguishing methods and agents Accountability Condition of personnel.
The decision as to who will do the evacuating
is often dictated by the fire.
Probably the most important issue regarding an evacuation is
when to order it
Wildland fire extinguishment operations should begin
by working up the flanks from with in the burned area, and then working towards the head.
The head of a wildland fire is
the fast growing and moving part of the fire.
When water is available and accessible
crews should saturate a perimeter that extends at least 50 ft.