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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
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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)
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
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
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