copyright fhfi 2006 fire investigations fire investigations fred herrera, cfi san diego, ca (760)...

Copyright FHFI 2006Copyright FHFI 2006

FIRE INVESTIGATIONSFIRE INVESTIGATIONSFred Herrera, CFIFred Herrera, CFI

San Diego, CASan Diego, CA

(760) 805-3842(760) 805-3842

www.fredherrera.com www.fredherrera.com [email protected]@fredherrera.com


NATIONWIDE STATSNATIONWIDE STATS

2 million fires reported2 million fires reported 9.4 billion dollars damage9.4 billion dollars damage 5,000 fatalities5,000 fatalities 100 firefighter fatalities100 firefighter fatalities 25,500 injuries25,500 injuries #1 cause of fires: cooking#1 cause of fires: cooking #1 cause of fire deaths: smoking#1 cause of fire deaths: smoking


BASIC FIRE SCIENCEBASIC FIRE SCIENCE


Fire Triangle / TetrahedronFire Triangle / Tetrahedron


COMBUSTIONCOMBUSTION

HeatHeat FuelFuel OxygenOxygen Uninhibited chemical chain reactionUninhibited chemical chain reaction

FOR FIRE SCENARIOFOR FIRE SCENARIO HEAT, FUEL, OXYGEN & EVENTHEAT, FUEL, OXYGEN & EVENT


HEAT TRANSFERHEAT TRANSFER


IGNITION OF SOLIDSIGNITION OF SOLIDS

Material must be pyrolyzed, or chemically Material must be pyrolyzed, or chemically decomposed, by the application of heat.decomposed, by the application of heat.

Density and surface area affect Density and surface area affect ignitability.ignitability.

Heat source must have ability to transfer Heat source must have ability to transfer sufficient heat, for sufficient duration, to sufficient heat, for sufficient duration, to fuel source.fuel source.


IGNITION OF LIQUIDSIGNITION OF LIQUIDS

Flammable / Flammable / CombustibleCombustible

Flash point below 100 FFlash point below 100 F Flammable liquidFlammable liquid Gasoline, -44 FGasoline, -44 F

Flash point 100 F or Flash point 100 F or aboveabove Combustible liquidCombustible liquid Kerosene, 100 FKerosene, 100 F

Vapors burn, not Vapors burn, not liquidliquid

Fuel / air mixtureFuel / air mixture LEL – Too leanLEL – Too lean UEL – Too richUEL – Too rich Explosive range – Explosive range –

Bingo!Bingo!


FIRE ORIGIN DETERMINATIONFIRE ORIGIN DETERMINATION

EXTERIOR EXAMINATIONEXTERIOR EXAMINATION INTERIOR EXAMINATIONINTERIOR EXAMINATION

Least damage to worstLeast damage to worst Identify area of originIdentify area of origin

RECONSTRUCTIONRECONSTRUCTION FIRE-SPREAD SCENARIOFIRE-SPREAD SCENARIO


FIRE CAUSE DETERMINATIONFIRE CAUSE DETERMINATION

AccidentalAccidental Appliance failureAppliance failure

NaturalNatural LightningLightning

IncendiaryIncendiary FraudFraud

UndeterminedUndetermined Black holesBlack holes

Examine indicatorsExamine indicators Identify possible Identify possible

causescauses Identify heat, fuel & Identify heat, fuel &

eventevent Rule out other causesRule out other causes Determine causeDetermine cause

Render opinionRender opinion


SYSTEMATIC APPROACHSYSTEMATIC APPROACHSCIENTIFIC METHODSCIENTIFIC METHOD

Recognize the needRecognize the need Define the problemDefine the problem Collect dataCollect data Analyze the dataAnalyze the data Develop a hypothesisDevelop a hypothesis Test the hypothesisTest the hypothesis Select final hypothesis (determine Select final hypothesis (determine

cause)cause)


Resistance heating of a plug


ARSON MOTIVESARSON MOTIVES

Crime concealmentCrime concealment Spite / revengeSpite / revenge Fraud / ProfitFraud / Profit ExcitementExcitement ExtremistExtremist VandalismVandalism PyromaniaPyromania


FIRE BOMBSFIRE BOMBS


DRUG LABSDRUG LABS


LAST CHANCE TO ASK!LAST CHANCE TO ASK!

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THE END!

copyright fhfi 2006 fire investigations fire investigations fred herrera, cfi san diego, ca (760)...

Documents

cause slide

copyright fhfi

heat transfer slide

smoking slide

plug slide

science slide

oxygen event slide

scenario heat