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Forest Layers - Iverson Forest · The element is heated and warms the pot which boils the water....

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S100A Recertification Test information “It is every person’s legal obligation to immediately report an open fire that is burning on, or within 1km of forest land or grass land and appears to be burning unattended or uncontrolled.” Forest Layers A wildland fire consists of plant community dominated by trees growing on a forest floor. Forest Fuels any substance that will ignite and combust (burn) is a fuel. There are three types of fuel: Ariel Fuel: combustible material higher than one meter (39 inches) above ground level; Surface Fuel: includes all combustible less than one meter above ground level and one years litter accumulation; and Ground Fuel: includes all combustibles substances bellow the surface little of the duff.
Transcript

S100A Recertification

Test information

“It is every person’s legal obligation to immediately report an open fire that is burning on, or within 1km of forest land or grass land and appears to be burning unattended or uncontrolled.”

Forest Layers

A wildland fire consists of plant community dominated by trees growing on a forest floor. Forest Fuels any substance that will ignite and combust (burn) is a fuel. There are three types of fuel:

Ariel Fuel: combustible material higher than one meter (39 inches) above ground level;

Surface Fuel: includes all combustible less than one meter above ground level and one years litter accumulation; and

Ground Fuel: includes all combustibles substances bellow the surface little of the duff.

The Fire Triangle

Three elements: fuel, oxygen and heat must be present to start and maintain a fire. In a forest fire: Fuel is the forest. Air provides the oxygen. Lightning or people introduce heat into the environment.

The fire triangle’s elements are linked; if one of the three elements is removed then the fire will be extinguished.

Heat Transfer Process Radiation: Is the transfer of heat from warm surfaces to cooler surroundings. Example heat from a fire place, or a campfire.

Convection: Is when heated molecules pass form one place to another. Example As warmer air rises cooler air rushes in creating a circular current.

Conduction: The transfer of heat through another object or mass. Example boiling water on the stove. The element is heated and warms the pot which boils the water.

Factors Influencing Fire Behaviour

Fuel Weather Topography Moisture Wind Slope

Size Precipitation Terrain Spacing Relative Humidity Aspect

Fuel Elevation

Fuel

Fuel Moisture: Fuel moisture is the most important fuel related factor affecting fire behaviour. Fire will ignite easier and spread faster in fuels with lower fuel moisture. How to determine fuel Moisture:

The amount of precipitation: Snow, rain. These are weather related factors that have a direct relationship with fuel moisture.

Type and condition of fuel: If the fuel is alive, it will not burn as fast

as if it was dead. As well as the type of fuel (logs, grass, and brush) all have different burn rates.

Heavy fuels: Can be categorized as slow burning fuels. These are things such as logs, stumps, deep duff, and large trees. These are harder to ignite, and burn longer and burn slower. Light Fuels: Can be categorized as fast burning fuels. These are grasses, small brush and trees, dead material, and needles. This fuel type has fast ignition time, and fast burn rate, but burns for a short duration. The Moisture content change due to weather has a faster affect on Light fuels than heavy fuels. Heavy fuels take longer to change moisture content. Since it has a larger surface area, and volume.

Relative Humidity:

Relative humidity influences fire behaviour by affecting fuel moisture. Relative humidity is calculated by the percentage of water to air (the mount of water vapour present in the air.).

Low Relative Humidity; tend to dry out forest fuels faster. High Relative Humidity tends to make forest fuels wetter, and

heavier. Relative humidity will decrease during the day (dry out) and increase at night. Fire Types

1. Ground fires: are fires that are contained to the ground, usually less

intense fires, and are the first stages of the fire.

2. Surface fires: are more active fires, that spread over a larger area, and have open and active flames.

3. Crown Fire (Intermittent): Large active fires spreading from the

ground into the crown. It’s a fully involved fire and should be re-asesed as it can be unpredictable at times.

4. Crown Fire: Fully involved fire, and can leap from one are to

another are. As well it is unpredictable and must use all safety precautions when working around such an active fire.

Major Factors affecting fire Behaviour Topography: There are three main topographaical factors that have the greatest influence on fire behaviour.

1. Slope a. Aspect

2. Terrain 3. Elevation

Slope: Is the single most important factor in the topographical effects on fire behaviour.

Slope make flames closer to the fuel source (uphill side). Convection heat rises upslope drying out the fuel source ahead of

the fire. Fire can be swept up slope from the draw of the convection heating

from the fire itself. Creating spot fires ahead of the fire itself (uphill, due to the draw of the convection heating.).

Burning debris and ambers can roll down hill igniting fire down slope and making the fire dangerous to fight.

Cooling at night causes the winds to change directions, moving the fire down slope, and warms during the day increasing the convection effect.

Aspect: Is a very important part of the slope factor. Aspect is the direction for which the slope faces. Southeast aspect, Northwest aspect.

Southeast slopes get the most sun, and dry out faster than any other slope. This gives southeast facing slopes higher temperatures and dryer fuels.

Terrain: Affects fire behavour by affecting the pattern and flow of the wind. Terrain and change the wind directional and speed.

Terrain creates eddies or turbulence, on leeward sides, from wind blowing across high features, such as ridges, cliffs, and other like features.

Wind speed increases as it come into tight valleys and knolls. This can help spread the fire faster upslope and through valley’s.

Steep sided gullies can create the “chimney effect” which raises the uphill wind speed dramatically.

Elevation: The higher the elevation the cooler the temperature. Certain atmospheric conditions a rise certain Thermal Belt, this is a layer of warm dry air trapped between the cooler higher elevation air and the warm moist air the valley bottoms. Here is where the moister and air temperature can create extreme fire conditions when least expected. Safety Note: Use extreme caution when fighting fire in higher elevations and steep ground. Make sure all safety resources are properly communicated, and that all fire fighters know the evacuation routes and procedures.

Fire Intensity Ranking System: Rank

1. No open flame, white smoke, smouldering ground fire.(below)

2. Visible open flame, surface fire only Unorganized flame front, little or no spread. (below)

3. Organized surface fire

Moderate rate of spread Vigorous surface fire. (below)

4. Organized surface flame front, disorganized crown involvement. Moderate to fast rate of spread on the ground Short range spotting Grey to black smoke

5. Organized crown fire front Moderate to long range spotting Independent spot fire growth Copper to black smoke

6. Organized crown fire front Moderate to long range spotting Independent spot fire growth Presence of fire balls and fire whirls

LCES LCES stands for lookout(s), communication(s), escape routes and safety zone(s). These are the same items stressed in the FIRE ORDERS and “Watchout” Situations. I prefer to look at them from a “systems” point of view, that is, as being interconnected and dependent on each other. It is not only important to evaluate each one of these items individually but also together they must be evaluated as a system. For example, the best safety zone is of no value if your escape route does not offer you timely access when needed. A key concept – the LCES system is identified to each firefighter prior to when it must be used. The nature of wildland fire suppression dictates continuously evaluating and, when necessary, re-establishing LCES as time and fire growth progress. I want to take a minute and briefly review each component and its interconnection with the others. Lookout(s) or scouts (roving lookouts) need to be in a position where both the objective hazard and the firefighter (s) can be seen. Lookouts must be trained to observe the wildland fire environment and to recognize and anticipate wildland fire behavior changes. Each situation determines the number of lookouts that are needed. Because of terrain, cover and fire size one lookout is normally not sufficient. The whole idea is when the objective hazard becomes a danger the lookout relays the information to the firefighter so they can reposition to the safety zone. Actually, each firefighter has the authority to warn others when they notice an objective hazard which becomes a threat to safety. Communications(s) is the vehicle which delivers the message to the firefighters, alerting of the approaching hazard. As is stated in current training, communications must be prompt and clear. Radios are limited and at some point the warning is delivered by word of mouth. Although more difficult, it is important to maintain promptness and clearness when communication is by word of mouth. Incident intelligence (regarding wildland fire environment, fire behavior and suppression operations) both to and from Incident Management (i.e. Command & General Staff) is of utmost importance. But I don’t view this type of communication a normal component of the LCES system. Entrapment occurs on a fairly site-specific level. Incident intelligence is really used to alert of hazards

(e.g.. “Watchout” situations) or to select strategical operations. LCES is primarily a Division function: responsibility should be here. Escape Routes are the path the firefighter takes from their current locations, exposed to the danger, to an area free from danger. Notice that escape routes is used instead of escape route(s). Unlike the other components, there always must be more than one escape route available to the firefighter. Battlement Creek 1976 is a good example of why another route is needed between the firefighter’s location and a safety zone. Escape routes are probably the most elusive component of LCES. Their effectiveness changes continuously. As the firefighter works along the fire perimeter, fatigue and spatial separation increases the time required to reach the safety zone. The most common escape route (or part of an escape route) is the fireline. On indirect or parallel fireline, situations become compounded. Unless safety zones have been identified ahead, as well as behind, firefighters retreat may not be possible. Safety Zone(s) are locations where the threatened firefighter may find refuge from the danger. Unfortunately shelter deployment sites have been incorrectly called safety zones. Safety zones should be conceptualized and planned as a location where no shelter is needed. This does not intend for the firefighter to hesitate to deploy their shelter if needed, just if a shelter is deployed the location is not a true safety zone. Fireline intensity and safety zone topographic location determine safety zone effectiveness. Again, a key concept – the LCES system is identified prior to when it must be used. That is lookouts must be posted with communications to each firefighter, and a minimum of two escape routes form the firefighter’s work location to a safety zone (not a shelter deployment site) every time the firefighter is working around an objective hazard. Safety and tactics should not be considered as separate entities. As with any task safety and technique necessarily should be integrated. The LCES system should be automatic in any tactical operation where an objective hazard is or could be present.

Command

ICS: Incident Command Systemfor wildland fire crews. Only Crew leaderspart of briefing, and debriefing meetings. is given to MOF reps, as well as that all Crew Leaders play an integral role in the communications safety hazards, danger trees, or other in's with the assigned MOF rep. other team members must relay any that information to the senior, or MOF Rep. Example of an ICS system:

MOF Rep

Crew

leader

ICS Admin

Command Structure for Fire Fighters

System is used to create a structured communicationsOnly Crew leaders can talk to MOF representative

part of briefing, and debriefing meetings. Crew Leaders are to make sure all is given to MOF reps, as well as that all information is relayed to their crews

integral role in the communications system; they must report any safety hazards, danger trees, or other information such as positions, duties and check

MOF rep. Only crew leaders can communicate with MOF Reps, other team members must relay any information to the crew leader who will

nior, or MOF Rep.

of an ICS system:

ICS

Comander

MOF Rep

Crew

leader

MOF Rep

Crew

leader

MOF Rep

ICS AdminICS

Operations

communications system representatives, and take

are to make sure all information crews.

they must report any , duties and check

leaders can communicate with MOF Reps, who will in turn relay

MOF Rep

Crew

leader

Operations

Hose pressure in wild fire operations

“ Rule of thumb is 2 psi per foot in elevation There are several lines to be used when fighting forest fires. Lines hohose, mini hoses, 1inch and 1 important to know your pressurepressure will be at the end of the line. can blow a line. The rule of thumb method is an average that can be used in areas where hoes type, and or elevation is unknown at Lined hoses you can lose on Unlined hoses can be from 1.0 Elevation: you lose 2 PSI every foot in

We have to have 35 PSI t the know what type of hose we are laying out, but as well as the type of ground we are going to.

Hose pressure in wild fire operations

Rule of thumb is 2 psi per foot in elevation ”. What dose this mean?

There are several lines to be used when fighting forest fires. Lines hose, or unlined hose, mini hoses, 1inch and 1 ¼ inch hoses. All have different pressure

pressure loss when fire fighting, so you can calculate how much pressure will be at the end of the line. Too little and you will ineffective, to much and you

The rule of thumb method is an average that can be used in areas where hoes type, and at the time of deployment.

Lined hoses you can lose on average 0.5 psi to 1.0 psi per foot of hose.from 1.0 to 5.0 PSI depending on the hose.

Elevation: you lose 2 PSI every foot in elevation.

t the nozzle for Ministry of Forest standards. Tknow what type of hose we are laying out, but as well as the type of ground we are going

Hose Elevation

What dose this mean?

se, or unlined pressure loss. It is

loss when fire fighting, so you can calculate how much and you will ineffective, to much and you

The rule of thumb method is an average that can be used in areas where hoes type, and

0.5 psi to 1.0 psi per foot of hose.

This requires us to know what type of hose we are laying out, but as well as the type of ground we are going

Source of Water and PSI: The source of water is very important, in determining PSI, if the source is very far away, and you’re on a moderate slope, you will have high friction and a drop in PSI, if your source is close, but steep you will have a large drop in PSI, at the nozzle. Source of water and distance are key factors in determining PSI.

Safety and Danger Trees Any and all Danger trees must be reported as soon as possible, flagged, and mapped for ICS (incident Command System). Once a danger tree is assessed by a certified danger tree assessor, they can deem the area unsafe, to work in, or request a faller to fall the tree, to remove the safety hazard. Only certified danger assessor can deem the work area is safe. Crew leaders must communicate with ICS, to ensure all safety strategies are meet. A danger tree assessor can be any one on the crew, which has been certified in Wildfire danger tree assessment. Only those qualified individuals can clear the areas of danger tree hazards.


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