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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

ccrivello@ranfpe.com518-275-0791

dnadeau@ranfpe.com518-275-0791

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

ccrivello@ranfpe.com518-275-0791

dnadeau@ranfpe.com518-275-0791