Firefighter Refresher:Fuel Types and Suppression

Tactics

Objective

• Provide wildland firefighters with information on fuel types and tactics that apply to Virginia. Providing local information on fuel types and tactics will result in a safer work environment for firefighters.

Major Fuel Types

• Brush with Grass Understory

• Pine Plantations

• Grass

• Cutover

• Pine/Hardwood

• Southern Rough

Brush and Grass Understory

• Importance of Fuel Moisture, Relative Humidity, Weather

• 10 HR Fuel Moisture less than 7%

• Relative Humidity less than 15%

• Direct Attack Impossible

• Indirect with good anchor point using dozers

• Expect rapid rate of spread

• Using Engines if conditions permit

• Foam or wet water

• Water source or tender nearby

• Use 2 Engines in tandem

• Adequate resources if going direct

• Rough terrain slow progress

• Threat of reburn

• 2 points to remember with weather– Watch wind for change in speed/direction– Watch relative humidity reaching critical

threshold limits

• Grass primary fire carrier

• Brush adds to mop-up difficulty

• Brush component varies: cedar, young pine, hardwood, reeds, vines

Pine Plantations

• Tactics vary depending on– Weather– Environmental conditions– Height of plantation trees

• Effects rate of spread (ROS), intensity, crowning, control problems

• Use of LCES, Standard Fire Orders, 18 Watch Out Situations

Plantation Trees Less Than Four Feet

• Grass primary carrier• Rate of spread high• Intensity low to medium• Wind speed less than 8 mph-Direct Attack• Wind speed 8-12 mph-Parallel Flank Attack• Wind speed greater than 12 mph-Indirect Attack• Fire Weather thresholds

– 20 foot winds 8-10 mph or higher– RH 30% or less

PLANTATION TREES 4-10 FEET

• Rate of spread high• Intensity medium to high• Resistance to control medium to high• Torching/crowning medium to high• Spotting a problem• Wind speed less than 8 mph-Direct Attack• Wind speed 8-12 mph-Parallel Flank Attack• Wind speed greater than 12 mph-Indirect Attack• Fire Weather Thresholds

– 20 foot wind 8-10 mph or higher– RH 30% or less

PLANTATION TREES 10-30 FEET

• Rate of spread medium-normally• Intensity medium to high• Resistance to control high• Crowning medium to high• Frequent spotting (control problem)• Presence of ladder fuels• Fire creates it’s own wind• Extremely dangerous fuels

• Indirect Attack during extreme burning conditions• Fire Weather Thresholds

– 20 foot winds 8-10 mph or higher– RH 30% or less

PLANTATION TREES 30 FEET OR GREATER

• Fire behavior in the Timber Group• Rate of spread medium-normally• Intensity medium to high• Resistance to control low to medium• Torching/crowning possible • Wind speed will determine-Direct, Parallel Flank

or Indirect Head Attack• Fire Weather Thresholds

– 20 foot wind 8-10 mph or higher– RH 30% or less

Grass Fuel Types

• Flat to rolling terrain

• Using Engines in tandem

• Pinching the head of fire

• Use of Dozers

• Weather Conditions for Grass Fires– Depends on Fuel Moisture and RH– RH less than 30% grass burns readily– RH less than 20% grass burns extremely well

Safety Concerns

• Grass fires can produce extreme flame lengths (FL) and rate of spread (ROS)

• Flank can become head with wind change

• Best to anchor and flank the fire

Cutover and Slash

• Primarily logging in pine stands

• Drought causes intensity and control problems

Tactics• Use of existing roads and skid trails• Slow line construction rate with dozer• Thorough mop-up• Use of Engines for mop-up, if possible• Spotting a problem

Pine/Hardwood Fuels

• Under story of vines and heavy needle drape• Canopy height of 60 feet or less• Fires usually fuel driven• Topography a problem in many areas (East &

West)• Active fire behavior when RH in lower 40%

range• Extreme fire behavior when RH below 20%

– Live fuel moisture in Mountain Laurel below 120%

Tactics

• Hand tools possible when fire behavior minimal and fire small• Engines limited by access• Tractor plows used for direct attack when low to moderate fire

behavior• Use roads and burning out with low RH

Southern Rough Fuels

• Usually found in South East Texas

• Can create explosive conditions

• Tractor plows used mostly

• Limited use of Engines

• Burn out line as go

Weather concerns for Southern Rough

– Can burn with RH 60% or greater– Crown fires possible in severe drought– Fire Behavior Thresholds

• 20 foot wind 8-10 mph or greater• RH 30% or less

Predictive Service Areas

KBDI

Weather Thresholds- RH 30% or Less, 20 foot wind speed 10 mph or more

Thresholds

• Dead Fuel Moisture• Fire Weather-Wind-speed, Humidity• NFDRS-ERC, BI • KBDI• Live Fuel Moisture

Weather Thresholds- RH 30% or Less, 20 foot wind speed 10 mph or more

Pocket Cards

• Fire Danger Area

• ERC-90th Percentile

• ERC-Years to Remember

• What Fire DangerTells You

• Past Experience

What does all this mean?

• Can we apply it to the “ real world”?

Look on Page 76 of yourIncident Response Pocket Guide

12-MAR-05: Fire Weather Forecast from WIMS @ 1700 Mountain Time ***** Texas ***** Elev Lat Long Mdl Tmp RH Wind PPT ERC BI SC KBDI HUN THOU TEN STL ADJ 410202 CADDO 619 33.7 95.9 7L 78 28 26 .00 5 55 118 109 10 21 5 5 V 410401 CLARKSVILLE 480 33.0 95.0 8D 77 26 18 .00 48 104 46 102 11 21 7 5 V 410501 TEXARKANA 200 33.3 94.0 8D 76 27 16 .00 48 96 39 149 14 23 7 5 V 411102 LINDEN 500 33.0 94.0 8D 76 27 16 .00 49 100 41 117 12 21 7 5 V 411401 GILMER 500 32.7 94.9 8D 77 27 17 .00 49 102 44 104 11 21 7 5 V 411901 CADDO LAKE NWR 200 32.6 94.1 8D 76 28 16 .00 50 100 41 80 13 22 7 4 H 412101 ATHENS 480 32.2 95.7 8D 78 31 26 .00 56 144 81 72 9 20 5 5 V 412202 HENDERSON 500 32.0 94.0 8D 76 28 17 .00 51 105 45 76 10 21 7 5 V Relative

Humidity (RH) will be between 15% and 30% in Gilmer today…

10-Hour Fuels will be between 5% and 7% in Gilmer today…

Adjective Fire Danger for

Gilmer today…VERY HIGH

Energy Release Component (ERC) will be above the 75th Percentile in Gilmer today…

20 foot Wind will be above 10 MPH in Gilmer today…

An Average Flame Length will be over 10 feet in Gilmer today…

12-MAR-05: Fire Weather Forecast from WIMS @ 1700 Mountain Time ***** Texas ***** Elev Lat Long Mdl Tmp RH Wind PPT ERC BI SC KBDI HUN THOU TEN STL ADJ 410202 CADDO 619 33.7 95.9 7L 78 28 26 .00 5 55 118 109 10 21 5 5 V 410401 CLARKSVILLE 480 33.0 95.0 8D 77 26 18 .00 48 104 46 102 11 21 7 5 V 410501 TEXARKANA 200 33.3 94.0 8D 76 27 16 .00 48 96 39 149 14 23 7 5 V 411102 LINDEN 500 33.0 94.0 8D 76 27 16 .00 49 100 41 117 12 21 7 5 V 411401 GILMER 500 32.7 94.9 8D 77 27 17 .00 49 102 44 104 11 21 7 5 V 411901 CADDO LAKE NWR 200 32.6 94.1 8D 76 28 16 .00 50 100 41 80 13 22 7 4 H 412101 ATHENS 480 32.2 95.7 8D 78 31 26 .00 56 144 81 72 9 20 5 5 V 412202 HENDERSON 500 32.0 94.0 8D 76 28 17 .00 51 105 45 76 10 21 7 5 V Relative

Humidity (RH) will be between 15% and 30% in Gilmer today…

10-Hour Fuels will be between 5% and 7% in Gilmer today…

Now look at the “Relative ease of chance ignition and spotting; general burning conditions” column on page 76 of the Incident Response Pocet Guide.

The colored dots on this map depict streamflow conditions as a percentile of normal, which is computed from the period of record for the current day of the year. Only stations with at least 30 years of record are used.Green = 25-75%Orange =10-24%Maroon = <10%Red = very little flow if any