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S 190 INTRODUCTION TO WILDLAND FIRE
BEHAVIOR EXAM 2024 | ALL QUESTIONS
AND CORRECT ANSWERS (ALREADY
GRADED A+) | VERIFIED ANSWERS |
LATEST VERSION
This aspect of a slope generally has lighter and sparser fuels, higher temperatures, lower humidity, lower fuel moisture. ------CORRECT ANSWER---------------South and Southwest This aspect of a slope will have less fire activity than a south facing slope -- ----CORRECT ANSWER---------------North Aspect This aspect of a slope has more shade, which causes heavier fuels, lower temperatures, higher humidity, higher fuel moisture. ------CORRECT ANSWER---------------North Aspect Expected fire behavior of a fire within a box canyon. ------CORRECT ANSWER---------------Very Dangerous extreme fire behavior. May react similar to fire in a wood burning stove or fireplace. Air will be drawn in from the canyon bottom creating very strong upslope drafts. These upslope drafts create rapid fire spread in the canyon. A fire in this type of canyon will create a chimney effect. ------CORRECT ANSWER---------------Box Canyon
Fire spread in this type of canyon can easily spread to fuels on the opposite side by radiation and spotting. ------CORRECT ANSWER---------------Narrow Canyon Dangerous fire conditions that can develop when a fire is burning in a narrow canyon. ------CORRECT ANSWER---------------PreHeating Spotting Rolling Material Increased Rate of Spread Wind Influences The direction of this type of canyon can alter the direction of prevailing winds. ------CORRECT ANSWER---------------Wide Canyons Fire spread across this type of canyon is not common. Strong differences in fire behavior will occur on north and south aspects. ------CORRECT ANSWER---------------Wide Canyons Natural Barriers to fire spread. ------CORRECT ANSWER---------------Rivers Lakes Rock Slides Man-Made Barriers to fire spread ------CORRECT ANSWER--------------- Roads Highways Reservoirs Fireline constructed by fire resources
Expressed as a percentage. ------CORRECT ANSWER---------------Relative Humidity When is relative humidity the lowest during the day? ------CORRECT ANSWER---------------Mid-Afternoon The degree of hotness or coldness of a substance ------CORRECT ANSWER---------------Temperature As temperature increases, relative humidity ____________. ------ CORRECT ANSWER---------------Decreases. Temperature and Relative Humidity have an inverse relationship. As temperature decreases, relative humidity ____________. ------ CORRECT ANSWER---------------Increases. Temperature and Relative Humidity have an inverse relationship. The precise location where a competent ignition source came into contact with the material first ignited and sustained combustion occurred. ------ CORRECT ANSWER---------------Point of Origin The side of the fire having the fastest rate of spread ------CORRECT ANSWER---------------Head of a fire
The part of a fire's perimeter that is roughly parallel to the main direction of fire spread. ------CORRECT ANSWER---------------Flank of a fire That portion of a fire edge opposite the head. ------CORRECT ANSWER---- -----------Rear of the fire That portion of a fire spreading directly into the wind or down slope. ------ CORRECT ANSWER---------------Rear of the fire The slowest spreading portion of a fire edge. Also called the heel of a fire. - -----CORRECT ANSWER---------------Rear of the fire The entire outer edge or boundary of the fire ------CORRECT ANSWER----- ----------Fire Perimeter The long narrow extensions of a fire projecting from the main body ------ CORRECT ANSWER---------------Fingers of fire Unburned indentations in the fire edge formed by fingers or slow burning areas ------CORRECT ANSWER---------------Pockets of a fire Area of unburned fuel inside the fire perimeter ------CORRECT ANSWER--- ------------Island
Spinning vortex column of ascending hot air and gases rising from a fire and carrying aloft smoke, debris, and flame. These range in size from less than one foot to over 500 feet in diameter. Have the intensity of a small tornado. ------CORRECT ANSWER---------------Firewhirl That portion of the fire with slower rates of fire spread and lower intensity, normally moving into the wind and/or down slope. ------CORRECT ANSWER---------------Backing fire That zone of a moving fire where combustion is primarily flaming. Is shallower in light fuels and deeper in heavy fuels ------CORRECT ANSWER---------------Flaming Front An advantageous location, usually a barrier to fire spread, from which to start constructing a fireline. this location is used to minimize the chance of being flanked by the fire while the line is being constructed ------CORRECT ANSWER---------------Anchor point An inclusive term for all constructed or natural barriers and treated fire edges used to contain a fire ------CORRECT ANSWER---------------Control Line The part of a containment or control line that is scraped or dug to mineral soil. ------CORRECT ANSWER---------------Fireline
Extinguishing or removing the burning material near control lines, felling snags, and trenching logs to prevent rolling after an area has burned, to make a fire safe, or to reduce residual smoke. ------CORRECT ANSWER--- ------------Mop-Up The status of a wildfire suppression action signifying that a control line has been completed around the fire, and any associated spot fires, which can reasonably be expected to stop a fire's spread. ------CORRECT ANSWER---------------Contained The completion of a control line around a fire, any spot fires, and any interior islands to be saved. Burnout any unburned area adjacent to the fire side of the control lines. Cool down all hot spots that are immediate threats to the control line, until the lines can reasonably be expected to hold under the foreseeable conditions. ------CORRECT ANSWER--------------- Controlled Difference between Contained and Controlled ------CORRECT ANSWER--- ------------Contained- Perimeter control line in place and expected to stop fire's spread Controlled- Perimeter control line in place and expected to hold fire's spread A unit of measure in land survey, equal to 66 feet (20 M) ------CORRECT ANSWER---------------Chain How many chains equal one mile? ------CORRECT ANSWER--------------- 80
This fire weather element is directly related to temperature distributions within the atmosphere. ------CORRECT ANSWER---------------Atmospheric Stability This type of atmosphere is one that resists upward motion. ------CORRECT ANSWER---------------A Stable Atmosphere Visual indicators of a Stable Atmosphere ------CORRECT ANSWER---------- -----1) Clouds in Layers
- Stratus type Clouds
- Smoke Column drifts apart after limited rise
- Poor visibility due to smoke or haze
- Fog Layers
- Steady winds The usual temperature stratification in the lower atmosphere. ------ CORRECT ANSWER---------------Characterized by a decrease in temperature with altitude. Condition where temperature increases with altitude. ------CORRECT ANSWER---------------Inversion Warm air over cold air= ___________. ------CORRECT ANSWER------------- --Inversion Stable or Unstable Atmosphere?
Inversion ------CORRECT ANSWER---------------Stable Fuel moisture content is usually higher. Updrafts created by fire are usually weak. Stable or Unstable Atmosphere? Clouds grow vertically & smoke rises to great heights ------CORRECT ANSWER---------------Unstable Stable or Unstable Atmosphere? Clouds in layers ------CORRECT ANSWER---------------Stable Stable or Unstable Atmosphere? Stratus Type Clouds ------CORRECT ANSWER---------------Stable Stable or Unstable Atmosphere? Cumulus Clouds ------CORRECT ANSWER---------------Unstable Stable or Unstable Atmosphere? Good Visibility ------CORRECT ANSWER---------------Unstable Stable or Unstable Atmosphere?
Indicators of a breaking inversion layer ------CORRECT ANSWER------------- --1) Increase in temperature
- Decrease in relative humidity
- Increase and/or Wind shift The most common inversions in a fire environment ------CORRECT ANSWER---------------Nighttime and Subsidence A region of warmer air typically found on the middle third of the slope ------ CORRECT ANSWER---------------Thermal Belt This region is characterized by the highest minimum temperature and the lowest night time relative humidity. ------CORRECT ANSWER--------------- Thermal Belt Fire behavior and activity expected within a thermal belt ------CORRECT ANSWER---------------"Rather" active. The large-scale sinking of air associated with high pressure systems. ------ CORRECT ANSWER---------------Subsidence Inversion An Atmosphere that encourages upward motion ------CORRECT ANSWER- --------------Unstable Atmosphere
Cold Air OVER Warm Air Represents _____________. ------CORRECT ANSWER---------------An unstable Condition 5 Visual Indicators of an unstable atmosphere ------CORRECT ANSWER--- ------------1) Clouds grow vertically and smoke rises to great heights
- Cumulus Clouds
- Good Visibility
- Gusty Winds
- Dust Devils and Fire Whirls A layer of air where temperature increases with altitude ------CORRECT ANSWER---------------Inversion This type of atmosphere encourages upward vertical motion ------ CORRECT ANSWER---------------Unstable Atmosphere This type of atmosphere resists upward motion ------CORRECT ANSWER-- -------------Stable Atmosphere The most critical fire weather element affecting fire behavior. ------ CORRECT ANSWER---------------Wind The most difficult fire weather element to predict ------CORRECT ANSWER---------------Wind
When does the greatest upslope wind speed occur? ------CORRECT ANSWER---------------Mid Afternoon Reasons for downslope winds ------CORRECT ANSWER---------------The air along the mountain slope at night cools faster than the air in the valley. The cool air sinks, producing the downslope wind. When can the greatest flow of downslope wind be expected? ------ CORRECT ANSWER---------------After midnight. Higher Elevation Effects on Temperatures and Relative Humidity ------ CORRECT ANSWER---------------Temperatures Decrease as elevation increases as Temperature decreases, RH increases. Lower Elevation Effects on Temperatures and Relative Humidity ------ CORRECT ANSWER---------------Temperatures Increase as elevation decreases. As Temperature increases RH decreases. A daytime breeze in which cooler air from high pressure over the coastal waters moves onshore to replace heated air rising above the warmer land mass. ------CORRECT ANSWER---------------Sea Breeze
A light nighttime breeze which originates over the relatively cool land, flows out over the warmer coastal waters. ------CORRECT ANSWER--------------- Land Breeze Land breezes usually occur during the _________. ------CORRECT ANSWER---------------Night Time Sea Breezes usually occur during the _________. ------CORRECT ANSWER---------------Day Time Examples of local winds ------CORRECT ANSWER---------------Up/down Slope winds Up/Down Valley winds Sea Breeze Land Breeze 5 Critical Fire Weather Conditions ------CORRECT ANSWER---------------1) Strong and Shifting Wind
- Very Low Relative Humidity
- High Temperatures
- Unstable Atmosphere
- Dry Lightning The boundary line between two different air masses, with cooler air behind and warmer air ahead. ------CORRECT ANSWER---------------Cold Front
Thunderstorm Dangers to firefighters ------CORRECT ANSWER---------------
- Erratic wind directions and speeds
- Heat rising from a fire can result in a convective column that can produce thunderstorms.
- Produce dangerous downdrafts
- Lightning that creates new fire starts This fire weather element is the most common indicator of unstable air ------ CORRECT ANSWER---------------Dust Devil Weather factors that can produce rapid fire spread ------CORRECT ANSWER---------------Thunderstorms Frontal Passages Fire Whirls Dust Devils Foehn Winds Indicators of Extreme Fire Behavior ------CORRECT ANSWER---------------
- Rapid Rate of Spread
- Intense Burning
- Spotting
- Crowning 7 Fire Environment Factors of Look Up, Down, & Around ------CORRECT ANSWER---------------1) Fuel Characteristics
- Fuel Moisture
- Fuel Temperature
- Topography (Terrain)
- Wind
- Atmospheric Stability
- Fire Behavior Look Up, Down, & Around Main Fuel Characteristics Factor Indicator ------CORRECT ANSWER------ ---------Continuous Fine Fuels Look Up, Down, & Around Main Fuel Moisture Factor Indicator ------CORRECT ANSWER--------------- Low RH (<25%) Look Up, Down, & Around Main Fuel Temperature Factor Indicator ------CORRECT ANSWER--------- ------High Temps >85 degrees F Look Up, Down, & Around Main Topography Factor Indicator(s) ------CORRECT ANSWER------------- --Steep Slopes (>50%) & Chutes Chimneys Look Up, Down, & Around Main Wind Factor Indicator ------CORRECT ANSWER--------------- Surface Winds above 10 mph
