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A f FiAnatomy of a FireDouglas Nadeau, MSFPE,
PE, CFPS, LEED APChristopher Crivello, MSFPE, PE
President of RAN Fire Protection Engineering, PC
Fire Protection Project Engineer at RAN Fire Protection Engineering, PC
Vice President of truVUE Inspection Technology
Agenda
IntroductionIntroductionShort History of Fire ProtectionFi D iFire DynamicsFire Protection SystemsEgressCase Study - Blessings Tavern FireCase Study Blessings Tavern Fire
Today’s Goal
Provide the basics of fire dynamicsProvide the basics of fire dynamicsGive reason to – “Fire protection means more than the Code”more than the CodeLook at buildings different tomorrowLearn how fire protection can save your life
Goals of Fire Protection
The goal of fire protection is:The goal of fire protection is:Protection of Life
Protection of Property
Continuity of Business OperationsContinuity of Business Operations
Rules of Thumb
Rules of Thumb – a procedure or ruleRules of Thumb a procedure or rule based on experience of practice
An example is:Loss of 5 psi in water pressure per story of a buildingIf it leaves ash behind it may be a Class A fire
Rules of Thumb
Rules of Thumb can and do lead to:Rules of Thumb can and do lead to:Myths
Misapplications
Bad DecisionsBad Decisions
Fire Protection Designs
Rules of ThumbRules of Thumb
The typical FPE answer
“It depends…”
Depends
Fire Protection Designs depends on:Fire Protection Designs depends on: The buildingTh fiThe fireThe occupantsThe fire departmentThe fire protection systemsThe fire protection systemsEtc…..
Depends
Rules of Thumb cannot substitute for:Rules of Thumb cannot substitute for:Knowledge of the codeS i tifi f tScientific factsGood design decisionsKnowing the reason for an action
We want to avoid “we always did it this way.”
Depends leads to
CommunicationCommunication … Building OwnerA hit tArchitectEngineerCode Enforcement OfficialsThe PublicThe Public
How Fire Protection is Perceived
There are 3 main classifications of thoughtThere are 3 main classifications of thought in relation to fire protection
Code BasedCode Based
Statistics Based
Performance Based
Agenda
IntroductionIntroductionShort History of Fire ProtectionFi D iFire DynamicsFire Protection SystemsEgressCase Study - Blessings Tavern FireCase Study Blessings Tavern Fire
Fire Protection Engineering History
To understand the practice of fireTo understand the practice of fire protection engineering it is essential to understand its historyunderstand its history.
A d d i i t d hA condensed version is presented here
Derivation of FPE
Codes, regulations, and fire departments beganCodes, regulations, and fire departments began after major fires:
1835 New York1861 London1871 Chicago1872 Boston1906 San Francisco
Rules initially from experience of fire fighters, builders architects & engineersbuilders, architects, & engineersLittle understanding of fire dynamics, structural behavior and human behaviorbehavior, and human behavior
Brief History of Fire Protection
Fire protection is one of the youngestFire protection is one of the youngest engineering trades
Great London Fire of 1666 - first building regulationsGreat London Fire of 1666 - first building regulations 1st professional fire brigade – 1824 (London)Patent for an automatic sprinkler was awarded toPatent for an automatic sprinkler was awarded to Henry S. Parmelee in 1874
Fire Protection 1850 - 1940
Building separation distances –Building separation distances conflagrations CompartmentationCompartmentationEgress travel distancesActive systems – sprinkler systemsPassive systems – fire resistance ratingsy g
Brief History of Fire Protection
1896 NFPA formed1896 NFPA formed
Di i li f fi i i d iDiscipline of fire engineering emerged in the early 20th century as a distinct di i li i t fidiscipline, in response to new fire problems posed by the Industrial R l tiRevolution
Fires of the 1960s
Issues with smoke managementIssues with smoke managementIssues with material selectionSt t l blStructural problemsLimited FPE knowledge but more complex buildingsFalse sense of security with codesyCodes slow progress of innovation
Today’s Codes & Standards
Construction is advancing much faster than theConstruction is advancing much faster than the codes
Construction methods,Size and complexity,Technology, ect…
Innovation advancing faster than educating engineers ability to use codes & standardsPerformance Based Designs
Agenda
IntroductionIntroductionShort History of Fire ProtectionFi D iFire DynamicsFire Protection SystemsEgressCase Study - Blessings Tavern FireCase Study Blessings Tavern Fire
Combustion Process
FIRE TRIANGLE FIRE TETRAHEDRON
http://svfd.net/SVFD%20Files/Articles/Foam/1B1_QR_Fire_Behavior.html. Retrieved November 30, 2015.
Fires can be prevented or suppressed b remo ing an one of theseby removing any one of these.
Chemical Reaction
A little more on the chemical reaction:To have combustion a chemical reaction between heat, fuel and oxygen
Foundation of how fires beging
Link
Suppressing the Fire Tetrahedron
Fuel – remove or shut off a supplyFuel remove or shut off a supplyOxygen – lower the amount within a compartmentcompartmentHeat – cool by applying a suppression
tagentChemical Reaction – use chemical suppressants or salts
What is a fire?
Uncontrolled exothermic reactionUncontrolled exothermic reaction
C b ti h i l tiCombustion – a chemical reaction involving fuel, heat, and an oxidizer
Types of Flames
Diffusion flamesDiffusion flames
P i d flPremixed flames
Link
Diffusion Flames
Fick’s Law –combustion where fuelcombustion where fuel gas and oxygen are transported to atransported to a reaction zoneN t l fl i fiNatural flaming fires are diffusion flames
Link
Premixed Flames
Mixing of fuel gas and oxygen prior to ignitionMixing of fuel gas and oxygen prior to ignition
Controlled example - Bunsen burnerUncontrolled example – confined space methane leak
Link
Fire Growth
A fire grows in a self-sustaining mannerA fire grows in a self sustaining manner
H t l d f fi i t f d tHeat released from a fire is transferred to other nearby fuel packages
Fire growth can be predicted – within g preason
Heat Transfer
Combustion gives off heat which can igniteCombustion gives off heat which can ignite nearby fuelsHeat energy always flows from hotter toHeat energy always flows from hotter to colder3 th d f h t t f3 methods of heat transfer
ConductionConvectionRadiation
Conduction
Heat transfer from direct contactHeat transfer from direct contact
Convection
Heat transfer through a fluid such as air orHeat transfer through a fluid such as air or liquid
Radiation
Transfer of heat in the form of an invisibleTransfer of heat in the form of an invisible energy wave
Becomes highly significant at higher t ttemperatures
Stages of Fire Growth
IgnitionIgnitionEstablished BurningG thGrowthFlashoverFull Room Involvement (FRI)Post FRIPost FRI
Stages of Fire Growth
Ignition – incipient phase, does not heat up theIgnition incipient phase, does not heat up the roomGrowth (Established Burning) –( g)
Waste basket type fire that is self sustaining Demarcation between prevention and building fire design
Fully Developed – enough fuel and oxygen il blavailable
Decay – occurs when all fuel is consumed
Fire Growth Curves
Q=t2
Fire Growth Curve
Beginbrand Groeifase Volontwikkeld Doven
°C
1000FULL ROOM INVOLVEMENT1000
800
FIRE GROWTH
INVOLVEMENT
POST FULL ROOM INVOLVEMENT
800FlashoverESTABLISHED
BURNING
600
400
200TIME
Terminology
1 Smoke – airborne products of1. Smoke airborne products of combustion in the air
2 Plume column of hot gases flames2. Plume – column of hot gases, flames, and smoke rising above a fire
3 C ili J t fl f k d th3. Ceiling Jet - a flow of smoke under the ceiling
Compartment Fire
Compartment Fire
Growth Stage – room heats up and ceilingGrowth Stage room heats up and ceiling layer development
Compartment Fire
Ceiling Layer Development – smokeCeiling Layer Development smoke increases, room heats up, negative pressure in room two layerspressure in room, two layers
Flashover
Temperature is about 600 C (1100 F)Temperature is about 600 C (1100 F)All materials spontaneously combustO l l t f d f th t itiOnly lasts a few seconds for the transition
Flashover
Rollover (Flameover)
Similar to FlashoverSimilar to FlashoverUsually in large roomsFi th b t f l k llFire growth between fuel package usually is not because of the upper gas layer d l tdevelopmentAlso known as Spreadover
Full Room Involvement
All combustible material in room burnsAll combustible material in room burns
Fi b til ti t ll dFire becomes ventilation controlled
Ventilation
Fires can be controlled by amount ofFires can be controlled by amount of ventilationAs a fire grows needs more oxygenAs a fire grows, needs more oxygen
Influence of Ventilation
Closed compartment might oxygen starveClosed compartment might oxygen starve the fire
Openings between compartments allows f f hfor fresh oxygen
New openings can restart a fire
Ventilation Controlled FireTEMP
T
VENT
TIME
VENT OPENING
Post Full Room Involvement (FRI)
Fuel controlled fireFuel controlled fire
C id d th d tConsidered the decay stage
Fire burns itself out
Backdraft
Oxygen regulates the fireOxygen regulates the fireFire slows the burning process (produce large amounts of CO)large amounts of CO)If a vent opens then fire will combust
idl (CO bi l i l ith O )rapidly (CO combines explosively with O2)Windows blow outCan be confused with an explosion
BackdraftTEMP
T
TIMETIME
Fire Modeling
Learn Theory vs Learning SoftwareLearn Theory vs. Learning SoftwareBetter to learn theory
Knowing the theory allows you to use any model
Knowing the software gives a false sense of modelingo ode g
Computer Modeling
Main types of computer modelsMain types of computer models1. Zone Models2 Computational Fluid2. Computational Fluid
Dynamics Models (CFD) – “Field Models”
3. Evacuation Models4. Probabilistic Modelsobab st c ode s
Know the limitationsKnow the limitations
The Results
Do the results make sense?Do the results make sense?Is the modeler able to compare the results to empirical correlations?to empirical correlations?There is no One AnswerWhat is the range of likely answers?Was there a sensitivity analysis run?y y
Modeling Reality
Models supplement engineering judgmentModels supplement engineering judgment, they cannot replace it
People assume that CFD and zone d l tmodels are easy to use
Reality is it takes a significant amount of work t h d l lto use such models properlyThey are easy to misuse
Agenda
IntroductionIntroductionShort History of Fire ProtectionFi D iFire DynamicsFire Protection SystemsEgressCase Study - Blessings Tavern FireCase Study Blessings Tavern Fire
Types of Fire Protection Systems
There are two main types:There are two main types:
A tiActive
PassivePassive
Active Fire Protection
A device or action that receives a stimulusA device or action that receives a stimulus before acting on a fire condition
Fire DepartmentFire DepartmentFire AlarmSprinkler SystemSprinkler SystemStandpipe SystemCl A t S tClean Agent System
Link
Passive Fire Protection
A building component that remains fixed inA building component that remains fixed in the building whether or not a fire condition existsexists
Compartment EnclosureStructural Fire ResistanceStructural Fire ResistanceFire Attack RouteEgress System
Link
Agenda
IntroductionIntroductionShort History of Fire ProtectionFi D iFire DynamicsFire Protection SystemsEgressCase Study - Blessings Tavern FireCase Study Blessings Tavern Fire
Can you believe real life?
This takes place in less than 3 min tesThis takes place in less than 3 minutes.
Egress System
A passive fire protection systemA passive fire protection system
I t t d ithInterconnected with:Occupant characteristicsType of occupancyConstructionSize of the buildingActive fire protection systems
Egress Computer Models
Predict egress timePredict egress timeTime = distance/walking speed
Could include occupant behavior
Should include fire scenario comparisonS ou d c ude e sce a o co pa so
Egress Computer Models
People real life reactions are complicatedPeople real life reactions are complicatedSight of smoke can change movementExposure to smoke/heat affect movingp g
Example ModelspPathfinderEXITTEvacnetSIMULEXEXODUS
Agenda
IntroductionIntroductionShort History of Fire ProtectionFi D iFire DynamicsFire Protection SystemsEgressCase Study - Blessings Tavern FireCase Study Blessings Tavern Fire
Blessings Tavern Fire
Blessings Tavern Fire
Blessing’s Tavern
Night Of The Fire
Night Of The Fire
Night Of The Fire
Night Of The Fire
Night Of The Fire
A Few Days Later
A Few Days Later
A Few Days Later
A Few Days Later
A Few Days Later
A Few Days Later
Conclusion
Facts of the Inaccuracy - With age comesFacts of the Inaccuracy With age comes experience:
Code have been reactionaryyFire is not an exact scienceIn a perfect world active and passive fireIn a perfect world active and passive fire protection installations would all work as intendedPreconceived ideas based on common sense is NOT science
Conclusion
Fire protection is an evolving scienceFire protection is an evolving science.
Hi t h h th t t blHistory has shown that acceptable practices change over time
Conclusion
The decisionsThe decisions
we make
impact livesimpact lives.
A f FiAnatomy of a FireDouglas Nadeau, MSFPE,
PE, CFPS, LEED APChristopher Crivello, MSFPE, PE
President of RAN Fire Protection Engineering, PC
Fire Protection Project Engineer at RAN Fire Protection Engineering, PC
Vice President of truVUE Inspection Technology
