S-190 Module 3 (Monitoring Fire Behavior)
What does "Look UP, DOWN, & AROUND" mean?
UP: Check out the WEATHER. This includes the Wind & the Atmospheric Stability DOWN: See what FUEL is there. This includes Fuel Characteristics, Fuel Moisture, & Fuel Temperature. AROUND: Se what the TOPOGRAPHY is like
One of the most common examples of, (blank), heat in a wildfire context is fire burning in a narrow canyon.
Radiating heat
What does radiating heat do?
Radiating heat preheats and dehydrates exposed fuels immediately adjacent to the fire and initiates combustion.
Even though liquid or sold fuel and oxygen may be present, heat must be added to liberate the, (blank), and initiate the combustion gases.
Fuel gases. Note: Only gases can burn without heat.
During, (blank), gases heated in a fire expand, become lighter, and rise.
Convection
Typically when trees begin torching, the fire is beginning to transition from a surface fire to a, (blank), fire.
Crown Fire
What are spot fires?
Spot fires are fires starting outside the perimeter of a main fire.
(Blank), Slopes encourage rapid ROS due to convective heating.
Steep Slopes
As identified in the IRPG, (Blank), and, (Blank), are the two most critical terrain indicators.
Steep Slopes & Chutes
Unlike a blowup, a, (blank), is of relatively short duration and does not radically change control plans.
Flare-up
What are the 5 key indicators to pay attention to when assessing fuel characteristics?
1. Continuous Fine Fuels 2. Heavy loading of dead & down fuels 3. Ladder fuels 4. Tight crowns spaces; & 5. Special Conditions: such as Firebrand sourcing or unusual fine fuels.
What are the THREE Primary methods for heat transfer?
1. Conduction 2. Convection 3. Radiation
(Blank), fire behavior is fire activity presenting a potential hazard to fire personnel if the tactics being used are not adjusted.
Problem
What are the THREE forms that fuels can come in?
1. Gas fuels (e.g. propane, butane, carbon monoxide) 2. Liquid fuels (e.g. gas, alcohol, paint); & 3. Solid fuels (e.g. dust, wood, plastic)
When assessing fuel temperatures, pay attention to THREE indicators:
1. High Temperatures (higher than 85 F) 2. High percent of fuels in direct sunlight; & 3. Increasing aspect fuel temperatures
Identify the THREE fuel factors MOST indicative of factors leading to problem or extreme fire behavior:
1. Moisture 2. Characteristics; & 3. Temperature
What do the THREE sides of the Fire Triangle consist of?
1. Oxygen sources 2. Heat sources; & 3. Fuel
What are the 4 traits that EXTREME fire behavior is characterized by?
1. Rapid Rate Of Spread 2. Intense burning 3. Spotting; & 4. Crowning
Not including the 4 fire behavior indicators about columns of smoke, what are the remaining 4 fire behavior indicators listed in the IRPG?
1. Smoldering fire picking up 2. Frequent spot fires 3. Trees torching; & 4. Small firewhirls beginning
What are the TWO most critical wind indicators?
1. Surface winds above 10 mph; & 2. Battling or Shifting Winds
What affects do surface winds have on a fire?
1. They help determine the direction of the fire spread 2. They help to carry firebrands ahead of the fire; & 3. They increase the supply of oxygen to the fire
What are TWO indicators that you should pay special attention to when dealing with a rapidly changing, wind-driven fire with intense burning?
1. Trees Torching 2. Small firewhirls beginning
A general rule of thumb is that an Relative Humidity of, (Blank), percent or lower means fire behavior will most likely increase dramatically.
25 percent
(Blank), winds change direction and then return to the original direction.
Battling Winds
A,(blank), occurs when there 's a sudden increase in ROS sufficient to prevent or rule out direct control of the fire.
Blow-up
(Blank), draw air in and create very strong upslope drafts.
Box Canyons
Fire is a, (blank), of combustion.
By-product
Chutes & Saddles allow heat to rise rapidly, creating a, (Blank), effect.
Chimney
A well-developed, (blank), of smoke is one of the three most critical fire behavior indicators to watch for.
Column
You interrupt the, (blank), process by disrupting one or more of the three required element in the fire triangle (fuel, oxygen, or heat).
Combustion Process
The amount of, (blank), required to reduce the moisture content of the fuel depends upon the physical and chemical makeup of the fuel and the percentage of atmospheric moisture.
Heat
According to the IRPG, what is the fuel temperature factor that you'll need to pay special attention to on the fireline?
High Temperatures
Hot convected gases moving up a slope can dry out fuels, lowering their, (blank).
Ignition Temperature
According to the IRPG, what is the fuel moisture factor that you should pay special attention to?
Low Relative Humidity
(Blank), Canyons increase spotting due to radiant and convective heating.
Narrow Canyons
Because fibrous materials such as plants and wood are poor, (blank), of heat, heat transfer by conduction has a limited effect on the spread of wildland fire.
Poor Conductors Note: One exception is when heat from a vehicle is conducted to the grass to cause a fire.
What are smoldering fires?
Smoldering fires are fire burning without flame and barely spreading.
Define combustion
The self-sustaining process of rapid oxidation.
A, (blank), fire is not as serious as a crown fire.
Torching Fire
(Blank), adds to the unpredictable nature of fire spread and delivers more oxygen to the fire.
Wind
(Blank), can effectively increase the amount of oxygen available to a fire and thereby increase the rate of combustion.
Wind
