Ignition Techniques (adapted from FL DOF)
Interagency Prescribed Fire
Training/
Fire Ecology and
Management, University of
Florida
Objectives
Characterize basic fire types
Link fire types to ignition patterns
Identify safety concerns
Describe when to use what
Methods of pile/windrow burning
Develop an ignition plan (you will do this later
in your Burn Plan)
Two situations requiring knowledge of
ignition techniques
Prescribed Fire: “Fire applied in a
knowledgeable manner to forest fuels on a
specific land area under selected weather
conditions to accomplish predetermined, welldefined management objectives”
Suppression burning is the use of prescribed
fire in a wildland fire situation
2 types of suppression burning

Counter Fire

Burn-out
Counter Fire
Fire applied to stop the forward spread of
uncontrolled fire
 GENERALLY NOT USED IN I.A.
 NEED AT LEAST 2 CREW MEMBERS
 ONLY IN CERTAIN FUEL TYPES ( not blowy leaf!)
 ONLY BY EXPERIENCED firefighters
 HIGH RISK
 TIME CRITICAL
Burn-out: when?
Often times on
wildfires, control lines
are established some
distance from fire edge
 Pockets
 Inaccessible areas
 Pre-existing control lines
 Areas of lesser fuel
concentrations
OBJECTIVES
Learn the Basic Fire Types- Related to Wind
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Characterize basic fire types
1. Backing
2. Head
3. Flanking
Link fire types to ignition patterns
Identify safety concerns
Describe when to use what
Methods of pile/windrow burning
Develop an ignition plan (you will do this later in
your Burn Plan)
What are the FACTORS TO DETERMINE FIRING
TECHNIQUES?
OBJECTIVES
WIND SPEED & DIRECTION
SMOKE SENSITIVE AREAS IN CLOSE
PROXIMITY?
CREW EXPERIENCE/KNOWLEDGE
1. Backing Fire
Used to establish baseline
Generally safest
Longer residence times
Slowest R.O.S.’s (1-3 ch/hr)
 ROS determined by Fuel Moisture
Excellent for heavy fuel loads
Used to burn around values
Generally not the primary technique
 Why not???
1. Backing Fire
1. Backing Fire
BURNS INTO THE WIND
Backing, Flanking Fire- video
1. Backing Fire- wind is important
1. Backing Fire
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When backfire is the primary technique,
consider:
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Windspeeds & fuel moistures
Establishing additional baselines
Orienting burn blocks
WIND
2. Strip-Head Fire
Most frequently used technique
Fastest method
Can manipulate intensity with strip width and time
interval
Consider:
 Width of strips
 Changing weather conditions
 Changing fuel conditions
 Using spots where necessary
 Spotting potential
 Convection activity
 “Closing the door” too soon
2. Strip-Head Fire
STAY BEHIND
DOWNWIND
IGNITOR!
2. Strip-Head Fire
• Intensity is controlled by line spacing and timing
• Spread rate is sensitive to windspeed
Fire- video
3. Flank Fire
REMAIN IN
SIGHT
MAINTAIN
PACE
3. Flank Fire
Can be an excellent tool, burn large areas with less
effort
Uniform fire intensities
Minimal spotting
Good in diverse fuel types
Consider:
 Winds (Dir. & Speed.)- must be steady!
 Number & experience of igniters- must be experienced!
 Communications & visibility (in unit)
 Conducive burn block orientation
 Using spot ignitions within the flanks
 Varying the flank ignition speed to control intensity
3. Flank Fire
FIRE BURNS 90°
TO WIND
FLANK FIRE
WALK INTO WIND
WIND
3. Flank Firepace of ignition
affects fire
behavior
4. Point Source (Spot) Fire
4. Point Source (Spot) Fire
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Excellent for large areas (aerial ignition)
Best technique for controlling intensities in
various weather conditions
Can be used in conjunction with strip head &
flank technique
Effective in heavy fuels
Burn manager can control where convection
occurs
Quickest way to complete ignition
Point Source (Spot) Fire
When spot firing, burn managers should consid
how to change fire intensity:
Width between spots
Width between strips
Changes in weather & fuels
Location of spots
Spotting potential
Difficulty in maintaining grid
Grid orientation to wind
Fast burn, high convection (why?)
Point Source (Spot) Fire, initiation
Point Source (Spot) Fire- growth
5. Ring Fire
5. Ring Fire
Traditionally used for site-prep
Minimizes short range spotting
Quick & easy
Early “point-of-no-return”
Traps wildlife, high intensity
High convective heat transfer
When using ring ignition, consider:
Access
Objectives (overstory, smoke plume,
speed)
Where to start
Crew experience
Begin with center point ignition
5. Ring Fire
How it’s really done:
 USE A VARIETY OF TECHNIQUES
OVER A RANGE OF WEATHER
CONDITIONS FOR MOSAIC BURN
PATTERNS
SECUREING A BASE LINE…
LINE WIDTH?
>2X FLAME LENGTH
DO NOT “CLOSE THE DOOR”!
CAN CAUSE FIRE WHIRLS (VORTICES)
USE CAUTION WALKING DOWNWIND!
USE CAUTION IN HEAVY FUELS
USE CAUTION ON SLOPES
USE CAUTION WHEN FIRES CONVERGE
ALWAYS WATCH WHAT YOUR FIRE IS DOING
FIRE GENERATED WINDS
KNOW LOCATIONS OF
PERSONNEL & EQUIPMENT
Ignition steps
1. Evaluate conditions, resources, and
objectives to determine desired fire
behavior.
2. Test burn and evaluation
3. Black line
4. Ignition techniques
5. Contingency plans
SAFETY should always be on your mind
L.C.E.S.
LOOKOUTS
COMMUNICATIONS
ESCAPE ROUTES
SAFETY ZONES