Transcript FIRE SUPPRESSION - Natural Resource Ecology and Management

Updates
Paper – draft due: Nov. 9
Group presentation: Nov. 18
FIRE SUPPRESSION
NREM 390 – 2 November 2010
Wildland Fire
 Categories of wildland fire
 Wildfire
 A fire that is unwanted (from an anthropocentric
point of view) with various means of ignition
 Prescribed Fire (human-ignited, natural-ignited)
 A fire that is wanted for management goals, and thus
promoted
 Escaped fire
 A term to describe a fire in transition to wildfire
What is Fire Suppression?
 The elimination or management of one or
more parts of the fire triangle to prevent
unwanted fire ignition and/or spread
 FUEL
 Separate fuel from other fuel (fireline)
 Eliminate by burning or mechanical removal
 HEAT
 Reduce heat with water, dirt, foam
 Inhibit combustion process by adding chemical retardants
 OXYGEN
 Smother the fire to remove oxygen
 Only special cases where this is possible
Strategies for Fire Suppression:
Direct and Indirect Attack
 Direct Attack
 Attempt at immediate fire suppression; should be done
by experienced personnel given enhanced risks
 Indirect Attack
 More typical, involves build-up of resources and
planning for fire suppression
 May use other techniques
Strategies for Fire Suppression:
Control, contain, confine
 Control
 Use of all resources to completely put the fire out
(federal government approach, e.g., old “10:00 AM rule”)
 Contain
 Using suppression methods to maintain a fire within
defined areas
 Confine
 Allowing a fire to burn without active suppression as long
as it remains within defined areas
Where would a prescribed fire operation typically fall?
Methods of Fire Suppression: Direct Control,
Perimeter Control, Prescription Control
DIRECT CONTROL
 Immediate & complete extinguishment of fire
(removal of one or more parts of the fire triangle)
 Typically used on small, isolated incidents (local
actions) or smaller parts of large fire complexes
 Examples?
 What concept was a famous means of direct
control?
Methods of Fire Suppression:
Perimeter control
 Encirclement of a fire, confinement of active parts
of a fire to prevent further fire spread
 Most common means of fire control in most
situations
 Hotspotting
 selectively attacking active potions through direct control
 When would the fire be contained? Or controlled?
 Contained: fire surrounded by a complete break in fuels
 Controlled: fireline strengthened such that flareups can
not cross the fire break
Methods of Fire Suppression:
Prescription Control
 Fire considered to be under prescription control as
long as it meets certain criteria, e.g., geographic
boundaries, fire behavior, weather conditions (=
“the prescription” of a fire management plan)
 Suppression actions may be take to confine the fire
(= “confinement” or a “confined fire”)
 Many of the same tactics utilized as with perimeter
control
Parts of a Fire
 Origin
 Point of ignition at which fire
began
 Flank
 Sides of the fire or burning area
 Heading fire (Head Fire)
 Leading edge of the fire as
determined by wind, slope, fuels
 Backing fire
 Fire that is moving against
prevailing abiotic factors
Parts of a Fire
 Spot Fires
 New fires or bodies of fire ignited by




embers transported away from main
body into receptive fuels
Pockets
 Unburned “peninsula” of fuel
Finger
 Fire that has split off from main body
and begun moving in its own (parallel)
direction
Island
 Unburned fuel within a fire area
Black
 Area within the perimeter of a fire
already burned out
Tactics for Fire Suppression: Firelines
 Handline = built by crew using handtools (mineral soils)
 Wetline = created by inundating fuels with water
 Plowline, catline, tractor line = created by heavy equipment





(mineral soil)
Mowed line = fuel cut & removed
Retardant line – lines made with chemicals
Foam line – lines made with chemical foams
Hotline – Fireline constructed in direct attack
Blackline = burning out area to eliminate fuels
Building
firelines
 Handline built by crew
using handtools
(mineral soils)
Blackline:
Burning out an
area to
eliminate fuels
Hotline: Fireline
constructed
under direct
attack
Tactics: Firing Operations
 Burning out
 cleaning out pockets of fuel by burning (parallel method of attack)
 Backfiring (“counterfiring”, “suppression firing”)
 Fire used as part of indirect
attack
 Burning large amounts of fuel in
advance of the main fire (usually
into the wind; not always)
 Replaces a fire over which
direct control is impossible with a
fire for which some control is
likely
Photo Example
Burning out
Backfiring
Functional Model for Fire Suppression
 Report/Dispatch
 Initial report & response to a new fire (wildfire) or
report to dispatch of new fire (prescribed)
 Size-up
 Taking stock of what the fire is doing upon arrival
 Matching the available suppression resources with the
character of the fire
 Initial Attack
 First resources on scene begin to address incident after
sizing-up incident
 “Smokechasing”
Functional Model for Fire Suppression
 Extended Attack
 When fire has grown too large to be managed strictly
on I-A and more resources are needed over a longer
period of time
 Mop-up
 Completely extinguishing all flame and burning fuels
within a burn area
 Demobilization
 Breaking down of a fire operation: I-A resources leave
scene, reverse of build-up
 Rehabilitation
 If needed, rehabilitation of burned area: removal of
equipment, repairing line, replanting if needed
Cerro Grande Fire
 Fire Management Plan (10 years)
 Phase 1 – grasslands in upper portion of unit
 Phase 2 – forested area on east and west sides
 Phase 3 – central wetter area
 Prescribed Fire – 2000
 Only Phase 1
 Escaped fire  wildfire  fire suppression
 Threatened the towns of Los Alamos and White Rock (18,000
residents)
 Threatened the Los Alamos National Laboratory
Bandelier National Monument:
Cerro Grande Prescribed Fire
Scenarios
 1) Slopover of main fire into the Sante Fe National Forest
 Direct attack, hotspotting, direct control, mop-up
 2) Slopover of main fire into the Sante Fe National Forest
 Burning out, coldtrailing, coldtrail, safety zone
 3) Spotting from main fire into the Phase III burn unit
 Smokechasing, prescription control, fireline, confinement
 4) Spotting from main fire into the Phase III burn unit, wind
from the north increasing in speed
 Anchor point, backfiring, perimeter control, extended attack,
escape route
Scenarios
 5) Spotting from main fire into the SE Phase II burn unit,
wind shift so that it is gusting from the west
 Sizeup, Fireline (explain what kind), perimeter control,
backfiring, anchor point
 6) Change in wind direction: originally from the N, now
coming from the NE and becoming gusty, causing fire to
spread into Baca Ranch
 Hotline, Contain, fireline (explain what kind), counterfiring,
backing fire, lookout