S-290 Intermediate Wildland Fire Behavior
S-290 Final Exam B with 100% complete
solution
List 3 methods of mass transport of firebrands on wild land fires? - ANS Conduction, wind,
and gravity
In an instable atmosphere: - ANS Smoke will continue to rise as long as it remains warmer
than the surrounding atmosphere and air parcels both rise and sink
Describe how convection influences transport of firebrands - ANS Rising heat produced from
fires can lift firebrands within the column. These firebrands can then be deposited ahead of the
fire as they fall out of the column.
The primary factors that affect rate of spread are: - ANS Changes in fuel type, wind speed,
and steepness of slope.
Which of the following changes would be expected to produce the largest change in ROS? -
ANS A slope reversal with a 6 mph wind blowing at one slope
The 4 fuel factors that affect the ignition of wild land fires are: - ANS Size and shape of fuels,
compactness or arrangement of fuels, fuel moisture, and fuel temperature.
Define fuel moisture content: - ANS The amount of water in fuel expressed as a percent of
the oven dry weight of that fuel.
The fire weather planning forecast, spot forecasts, red flag warnings, and smoke management
forecasts are products issued by: - ANS The National Weather Service
Which one or more of the following statements are correct regarding wind driven and plume
dominated fires: - ANS Wind driven fires are easier to predict the direction of spread
Plume dominated fires have similar hazards to thunderstorms
Plume dominated fires the convected column dictates the fire activity
List the 3 methods used in the field to determine slope percent: - ANS Clinometer/abney,
measurement using a stick propped into slope and percent slope formula, slope meter estimate
Upslope winds are typically weakest on what aspect: - ANS North
, The 3 stages of crown fire development include: - ANS Passive, active, and dependent
Slope effects fuel availability to burn because: - ANS Fuels are preheated upslope through
radiation and convection
Rolling firebrands ignite fuels below
Which of the following topographic variations in wind speed would expect on a sunny summer
afternoon: - ANS Highest wind speeds on upper windward slopes
Lowest wind speeds on downwind slopes
Inputs used to determine fine dead fuel moisture content are: - ANS Time of day, month of
year, dry bulb temp, RH, aspect, percent slope, and shading of surface fuels
General winds are: - ANS Large scale winds caused by the pressure gradients associated
with highs and lows.
If the wet bulb is not read at it's lowest point on a psychrometer - ANS The calculated Rh
would be too high
Branches above the fire are receiving heat by: - ANS Radiation and convection
RH is: - ANS The ratio of the amount of water vapor in the air to the amount of water vapor
the air can hold when saturated at the same temperature.
Select the correct statement regarding the shape of the country and it's effect on wild land fire
behavior: - ANS The shape of the country can influence the curing of the fuels as well as the
intensity and spread of fires.
Select the statement that best describes the affect of slope on fuels: - ANS A fire starting at
the base of a slope has more fuel available for spread
Fuel beds on S and SW aspects are usually drier
Of the 3 methods for obtaining live fuel moistures, the following produces the most accurate
results: - ANS Collecting samples, weighing them, drying them and then weighing them
again.
List in order the 3 main fuel types from slowest to fastest rate of spread: - ANS Litter, crown,
grass
7 day significant fire potential, monthly fire weather/fire danger outlooks, and seasonal
assessments, are all products produced by what organization. - ANS Land Management
Predictive Services
S-290 Final Exam B with 100% complete
solution
List 3 methods of mass transport of firebrands on wild land fires? - ANS Conduction, wind,
and gravity
In an instable atmosphere: - ANS Smoke will continue to rise as long as it remains warmer
than the surrounding atmosphere and air parcels both rise and sink
Describe how convection influences transport of firebrands - ANS Rising heat produced from
fires can lift firebrands within the column. These firebrands can then be deposited ahead of the
fire as they fall out of the column.
The primary factors that affect rate of spread are: - ANS Changes in fuel type, wind speed,
and steepness of slope.
Which of the following changes would be expected to produce the largest change in ROS? -
ANS A slope reversal with a 6 mph wind blowing at one slope
The 4 fuel factors that affect the ignition of wild land fires are: - ANS Size and shape of fuels,
compactness or arrangement of fuels, fuel moisture, and fuel temperature.
Define fuel moisture content: - ANS The amount of water in fuel expressed as a percent of
the oven dry weight of that fuel.
The fire weather planning forecast, spot forecasts, red flag warnings, and smoke management
forecasts are products issued by: - ANS The National Weather Service
Which one or more of the following statements are correct regarding wind driven and plume
dominated fires: - ANS Wind driven fires are easier to predict the direction of spread
Plume dominated fires have similar hazards to thunderstorms
Plume dominated fires the convected column dictates the fire activity
List the 3 methods used in the field to determine slope percent: - ANS Clinometer/abney,
measurement using a stick propped into slope and percent slope formula, slope meter estimate
Upslope winds are typically weakest on what aspect: - ANS North
, The 3 stages of crown fire development include: - ANS Passive, active, and dependent
Slope effects fuel availability to burn because: - ANS Fuels are preheated upslope through
radiation and convection
Rolling firebrands ignite fuels below
Which of the following topographic variations in wind speed would expect on a sunny summer
afternoon: - ANS Highest wind speeds on upper windward slopes
Lowest wind speeds on downwind slopes
Inputs used to determine fine dead fuel moisture content are: - ANS Time of day, month of
year, dry bulb temp, RH, aspect, percent slope, and shading of surface fuels
General winds are: - ANS Large scale winds caused by the pressure gradients associated
with highs and lows.
If the wet bulb is not read at it's lowest point on a psychrometer - ANS The calculated Rh
would be too high
Branches above the fire are receiving heat by: - ANS Radiation and convection
RH is: - ANS The ratio of the amount of water vapor in the air to the amount of water vapor
the air can hold when saturated at the same temperature.
Select the correct statement regarding the shape of the country and it's effect on wild land fire
behavior: - ANS The shape of the country can influence the curing of the fuels as well as the
intensity and spread of fires.
Select the statement that best describes the affect of slope on fuels: - ANS A fire starting at
the base of a slope has more fuel available for spread
Fuel beds on S and SW aspects are usually drier
Of the 3 methods for obtaining live fuel moistures, the following produces the most accurate
results: - ANS Collecting samples, weighing them, drying them and then weighing them
again.
List in order the 3 main fuel types from slowest to fastest rate of spread: - ANS Litter, crown,
grass
7 day significant fire potential, monthly fire weather/fire danger outlooks, and seasonal
assessments, are all products produced by what organization. - ANS Land Management
Predictive Services
