Ventilation Controlled Fires Fire Development and Potential for Extreme Fire Behavior

Central Whidbey Island Fire & Rescue

Serving Coupeville, Greenbank, & Central Whidbey Island

CentralFire Department Whidbey Island Fire Instructor’s & Rescue ConferenceProfessionalism (FDIC) ● Integrity 2011 ● Compassion ● Excellence REV 1.0 Central Whidbey Island Fire & Rescue

 Whidbey is a large island in the Puget SdSound (North west WWhiashington )  CWIFR is a combination department serving 50 mi2 (129 km2) from four fire stations  Predominant fire risks in this rural district are private dwellings and small to mid‐size commercial occupancies

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Philosophy

In order to carry on your business properly, it is necessary for those who practice it to understand not only what they have to do, but why they have to do it… No fireman can ever be considered to have attained a real proficiency in his business until he has thoroughl y mast ered this combinati on of theory and practice.

Fire Protection, 1876 Sir Eyre Massey Shaw Chief, London Fire Brigade

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Overview

 Compartment Fires  Fire Development  Burning Regime  Vent Controlled Fires  EtExtreme Fire BBhehav ior  UL Tactical Considerations  Practical Applications

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Compartment Fire

A compartment is an enclosure such as a room within a building

The term compartment fire is also used for fires involving multiple compartments

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Building Factors Area

Fire Compartmentation Size Load Required Fire Flow Type Stories Height Mass Fuel Ceiling Structural Contents Construction Ventilation Profile Non Structural

Thermal Building Openings Properties Actual Potential Fire Protection Normal Systems HVAC Ventilation

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.00.1 Fire Load

MJ/kg The mass and burning 40 characteristics of the fuel encountered in compartment 30 fires has changed over time. 20

10 Fuel Load 1942 1980 Wood Polystyrene Low 9.9 kg/m2 29.3 kg/m2 2 2 Polyurethane Polyethylene High 64.4 kg/m 125.5 kg/m Foam

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Compartmentation

 Fire develops more quickly in a small compartment.  Highly compartmented buildings may slow fire spread.  Large compartments contain more air and may have a substantial fuel load.

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Ventilation Profile

Existing and Potential Openings

 Normal building ventilation and compartmentation  Ventilation openings created by exiting civilian occupants  Tactical action taken by firefighters  Unplanned ventilation All changes to the ventilation profile may influence fire behavior!

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Basic Considerations

 Under given conditions, compartment fires behave consistently

 Staffing has no impact on fire ddiynamics

 Context is critical!

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Basic Considerations

 Fuel Characteristics  Compartmentation  Ventilation Profile

Firefighters have two primary strategies to influence fire behavior (fire control & ventilation)

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Fire Dynamics

NIOSH F2010‐10  Ensure that the incident commander and firefighters understand the influence of ventilation on fire behavior

 Consider developing more comprehensive training requirements for fire behavior FF/EMT‐P Brian Carey (Fatality) FF/EMT‐P Kara Kopas (Injured) in NFPA 1001 and NFPA 1021.

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Building Blocks for Understanding

 Stages of Development . Incipient . Growth . Fully Developed . Decay  Heat Release Rate (()HRR)  Burning Regime . Fuel Controlled . Ventilation Controlled

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Stages of Fire Development

HRR

Incipient

Fully Growth Developed Decay Time

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Stages of Fire Development

 The stages dibdescribe a complex process.  Multiple influencing variables are involved.  Fire development can vary from this simple sequence

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Burning Regimes

 Fuel Controlled Fire growth is predominantly limited by the fuel availability and characteristics  Ventilat ion CClldontrolled Fire growth is predominantly lim ite d by availa ble oxygen

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Fuel and Power Key Concepts

 The chemical content of fuel influences heat of combustion and heat release rate (HRR).

 Heat of combustion is the total amount of energy released when a specific amount of fuel is oxidized.

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Fuel and Power Key Concepts

 Power is an amount of energy delivered over a specified time

 Heat release rate (HRR) is the energy release per unit of time.

Units of Measure

Energy Joules (J) Btu Power Watts (J/s) Btu/s

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Heat Release and Oxygen Key Concepts

Oxygen Consumption

 13.7 MJ/kg of O2

 21% O2 in Air  3.00 MJ/kg of Dry Air  3.60 MJ/m3 of Dry Air

William Thornton (1917) The Relation of Oxygen to the Heat of Combustion of Organic Compounds

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Heat Release and Oxygen Key Concepts

The door should be kept shut while the water is being brought, and the air excluded as much as possible, as the fire burns exactly in proportion to the quantity of air which it receives. James Braidwood (1866) Fire Prevention and Fire Extinction

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Heat Release Rate Key Concepts

 Heat release rate (HRR) is the driving force for the fire.  Room temperature and concentration of toxic combustion products are correlated with HRR.  High HRR indicates a high threat to life.

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Heat Release Rate Key Concepts

HRR varies over time, increasing as more fuel becomes involved and then falling as fuel is consumed.

HRR (kW)

Time (()s)

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Visualization

Visualize packages of fuel materials in terms of heat of combustion and potential peak HRR

770 MJ Heat Release 3003.00 MW Peak HRR

Wood and Polyurethane Sofa 51.3 kg (113 lbs)

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Visualization

HRR (kW) 4000

3000

2000

1000

0 0 300 600 http://www.fire.nist.gov/fire/fires/fires.html Time (s)

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Incomplete Combustion

What happens if the fuel is not completely oxidized during combustion?

Incomplete combustion results in production of carbon monoxide, carbon particulate and a wide range of other substances (depending on the fuel) as well as accumulation of unburned pyrolysis products.

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 What is Smoke

 Product of incomplete Smoke is Fuel! combustion & pyrolysis  Complex aerosol (gas, vapor, particulate)  Toxic and flammable  Fluid that can transfer energy (conv ectio n adand radi ati on )

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Upper Layer Hazards

 As a fire grows hot smoke Smoke is Fuel forms a layer above the cooler air below.  This upper layer presents several hazards. . RditRadiant and CCtionvective Heat Flux . Readily ignitable gas phase fuel

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Contemporary Fire Development

HRR

Fuel Ventilation Controlled Controlled

Ventilation Increased

Time

 Flashover  Backdraft  Smoke Explosion  Flash Fire

Firefighters may be able to define these terms, but often miss key indicators of potential extreme fire behavior!

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Phenomena that result in rapid Extreme Fire Behavior fire progression and present a significant threat to firefighters

Rapid transition and Transient Events sustained increase in HRR Overpressure

Ignition and rapid or Confined explosive combustion Smoke BkdftBackdraft Explosion Step Events

Pre‐Mixed High Fuel/Air Fuel Ventilation Flammable Concentration Controlled Controlled Fuel/Air Concentration

Flash Flashover Vent‐Induced Flashover Fire

Moderate Fuel/Air Pre‐Mixed Flammable Concentration Fuel/Air Concentration Limited Mass or Confinement Minimal HRR Sufficient to Result in Full Surface Overpressure Involvement Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Extreme Fire Behavior Step Event

HRR

Fuel Ventilation Controlled Controlled

Ventilation Increased

Time

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Extreme Fire Behavior Transient Event

HRR

Fuel Ventilation Controlled Controlled

Ventilation Increased

Time

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Extreme Fire Behavior Ambiguous Events

HRR

What is This?

Fuel Ventilation Controlled Controlled

Ventilation Increased

Time

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Experience

 Washington DC ‐ Flashover  New York City ‐ Backdraft  Duango CO ‐ Smoke Explosion  San Pablo CA ‐ Flash Fire

CFBT‐US, LLC has developed case studies for each of these incidents. The cases can be downloaded at www.cfbt‐us.com

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Washington DC Flashover

May 30, 1999 3146 Cherry Road NE

Side A

Side C

Firefighter Anthony Phillips Fifihirefighter Lewis Mathews

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 New York NY Backdraft

March 28, 1994 June 17, 2001 62 Watts Street 12‐22 Astoria Boulevard

Captain John Drennan Firefighter John J. Downing Firefighter James Young Firefighter Brian D. Fahey Firefighter Christopher Seidenburg Firefighter Harry S. Ford

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Durango CO Smoke Explosion

January 22, 2008 764 Main Street

Nine Firefighters & Fire Officers Injured

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 San Pablo CA Flash Fire

July 27, 2007 148 Michele Drive

Captain Mathew Burton Engineer Scott Desmond

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 UL Research: Lessons Learned

Impact of Ventilation on Fire Behavior in Legacy & Contemporary Residential Construction

Practical Application of Fire Dynamics Research

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 UL Research: Lessons Learned

 Most fires beyond the incipient stage are vent controlled when we arrive  If vent controlled increased ventilation results increases HRR  The entry point is a ventilation opening  Ventilation openings (including the entry poit)int) create a flow path

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 UL Research: Lessons Learned

 Ventilation and fire attack must be closely coordinated  Tactical ventilation will not return the fire to a fuel controlled burning regime  If the fire has self‐vented it will grow quickly when ventilation is increased  A closed door maintains a more tenable environment in a compartment

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 UL Research: Lessons Learned

 Water applied into the fire compartment from the exterior reduces HRR and does not push fire to uninvolved compartments  Low oxygen concentration limits flaming combustion in adjacent compartments (this can change with ventilation)

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Situational Awareness

 Recognize the hazards presented by ventilation controlled fires  Identify key fire behavior indicators and anticipate fire development  Be proactive in controlling the fire environment

Central Whidbey Island Fire & Rescue Professionalism ● Integrity ● Compassion ● Excellence REV 1.0 Central Whidbey Island Fire & Rescue

Serving Coupeville, Greenbank, & Central Whidbey Island

Chief Ed Hartin, MS, EFO, MIFireE, CFO Central Whidbey Island Fire & Rescue 1164 Race Road Coupeville, WA 98239 [email protected] ed.hartin@cfbt‐us.com (360) 914‐7704 (5 03) 793‐1296

CentralFire Department Whidbey Island Fire Instructor’s & Rescue ConferenceProfessionalism (FDIC) ● Integrity 2011 ● Compassion ● Excellence REV 0.11.0