Tactical PPV. This powerpoint was created using information provided to us by Chief Bob Nicks of the...

Tactical PPVTactical PPV

Tactical PPVTactical PPV

This powerpoint was created using This powerpoint was created using information provided to us by Chief information provided to us by Chief

Bob Nicks of the Austin Fire Bob Nicks of the Austin Fire Department and Professor O.A. Department and Professor O.A.

Ezekoye of the University of Texas.Ezekoye of the University of Texas.

ObjectivesObjectives The Firefighter should be able to:The Firefighter should be able to:

Describe why coordinated ventilation Describe why coordinated ventilation provides the “context” for the development provides the “context” for the development of fireground tacticsof fireground tactics

Describe how fan positioning, building size Describe how fan positioning, building size and configuration, wind, and vent size affect and configuration, wind, and vent size affect ventilation ventilation

Describe how under-ventilation or improper Describe how under-ventilation or improper ventilation can create an unsafe interior ventilation can create an unsafe interior

Perform PPV during Investigative Mode to Perform PPV during Investigative Mode to assist in fire locationassist in fire location

ObjectivesObjectives The Firefighter should be able to:The Firefighter should be able to:

Perform PPV during Offensive Mode fire Perform PPV during Offensive Mode fire attack, coordinating search, ventilation attack, coordinating search, ventilation and fire attack.and fire attack.

Perform PPV outside the fire corridor to Perform PPV outside the fire corridor to reduce hazards to Firefighters and reduce hazards to Firefighters and decrease damage to structure and decrease damage to structure and contents (adjacent structures and attics).contents (adjacent structures and attics).

Perform PPV post-knockdown to assist in Perform PPV post-knockdown to assist in overhaul without increasing risk of overhaul without increasing risk of rekindle.rekindle.

Tactics and Fire Tactics and Fire VentilationVentilation

Venting for Venting for fire fire situations is often misapplied and situations is often misapplied and careful thought should be given to the objective at careful thought should be given to the objective at hand. The main objective must be to improve interior hand. The main objective must be to improve interior conditions for firefighters by reducing heat levels and conditions for firefighters by reducing heat levels and improving visibility - improving visibility - Paul Grimwood, British Fire ServicePaul Grimwood, British Fire Service

An analysis of the last 8 years of NIOSH Firefighter An analysis of the last 8 years of NIOSH Firefighter fatality reports show that in fatality reports show that in every fatalityevery fatality where fire where fire behavior was a causal factorbehavior was a causal factor in the Firefighter death, in the Firefighter death, ventilation was not performed or performed ventilation was not performed or performed incorrectly. incorrectly.

Coordinated PPV will make the fireground safer; Coordinated PPV will make the fireground safer; uncoordinated PPV or PPV employed by uncoordinated PPV or PPV employed by improperly training Firefighters can be improperly training Firefighters can be dangerous!dangerous!

Tactics and Fire Tactics and Fire VentilationVentilation

Ventilation is the most complex Ventilation is the most complex tactic to perform correctly because tactic to perform correctly because proper ventilation requires:proper ventilation requires: Knowledge of proper ventilationKnowledge of proper ventilation

As an industry, information on the subject As an industry, information on the subject varies widely. varies widely.

All companies working on scene must All companies working on scene must work together to coordinate their effortswork together to coordinate their efforts

To coordinate on-scene efforts, all To coordinate on-scene efforts, all Firefighters must know their role and how Firefighters must know their role and how their role affects others on the fireground.their role affects others on the fireground.

Tactics and Fire VentilationTactics and Fire VentilationTactics determine how the fire fighting operation is structured, put together, and creates an entirety of parts.

If smoke is the primary hazard, the coordination of ventilation activities should become the context for all fireground tactical activities.

Explained later in detail during the tactical portion

What is “Proper What is “Proper Ventilation”?Ventilation”?

Coordinated Fire AttackCoordinated Fire Attack 360360

Locate Fire – Determine Risk of PPVLocate Fire – Determine Risk of PPV Determine Vent Opening LocationDetermine Vent Opening Location Determine when to make vent – Coordinate; Do Determine when to make vent – Coordinate; Do

not vent until attack crew is ready to movenot vent until attack crew is ready to move Fire AttackFire Attack

Employ PPV before entry, Employ PPV before entry, Observe effectsObserve effects Make Fire AttackMake Fire Attack

Other Tactical FunctionsOther Tactical Functions Must ensure “Vent for Life”, Laddering, and/or Must ensure “Vent for Life”, Laddering, and/or

Additional Forcible Entry do not negatively affect Additional Forcible Entry do not negatively affect ventilationventilation

Backup Team stands down until entry of Fire Backup Team stands down until entry of Fire Attack Team Attack Team

AFD Close CallsAFD Close Calls

Between 1998 and 2003 the Austin Between 1998 and 2003 the Austin Fire Department experienced FIVE Fire Department experienced FIVE near death fire related events at near death fire related events at three incidentsthree incidents

1.1. 903 E. Riverside Drive (Two 903 E. Riverside Drive (Two Firefighters)Firefighters)

2.2. 2213 S. Lakeshore Drive (Two 2213 S. Lakeshore Drive (Two Firefighters)Firefighters)

3.3. 837 E. Oltorf Street837 E. Oltorf Street

Common Incident Common Incident FactorsFactors

All Firefighters were hospitalized All Firefighters were hospitalized with thermal and/or smoke related with thermal and/or smoke related injuriesinjuries

All were minutes or possibly seconds All were minutes or possibly seconds from deathfrom death

Proper ventilationProper ventilation could have could have prevented these injuriesprevented these injuries

Common Fire Common Fire CharacteristicsCharacteristics

All fires were in a All fires were in a ventilation ventilation controlledcontrolled state at the time of the state at the time of the event event ((A fire where the fire growth is determined by the amount of air A fire where the fire growth is determined by the amount of air available. A ventilation-controlled fire occurs when there is not enough air to burn available. A ventilation-controlled fire occurs when there is not enough air to burn all the materials being pyrolyzedall the materials being pyrolyzed))

All were located in residential All were located in residential structuresstructures

All fires were located on the second All fires were located on the second floorfloor

All were either All were either unventilatedunventilated or or ventilatedventilated improperly improperly

2213 S. Lakeshore Drive

INITIAL DISPATCHINITIAL DISPATCH0426 HOURS0426 HOURS

ENGINE COMPANY 22ENGINE COMPANY 22

HEAVY BOX ALARM COMPLEMENTHEAVY BOX ALARM COMPLEMENT

RESPONDING UNITSRESPONDING UNITS

UNITUNITENGINE 22ENGINE 22ENGINE 1ENGINE 1ENGINE 50ENGINE 50ENGINE 6ENGINE 6TRUCK 1TRUCK 1TRUCK 35TRUCK 35RESCUE 14RESCUE 14BATTALION 6BATTALION 6BATTALION 4BATTALION 4

PERSONNELPERSONNEL334433444433221111

1st floor door open

2nd floor looking toward fire apartment

CRITICAL FACTORSCRITICAL FACTORS ““FIRE KNOCKED DOWN”FIRE KNOCKED DOWN” VENTILATION-CONTROLLED FIRE VENTILATION-CONTROLLED FIRE

FUEL RICHFUEL RICH OXYGEN STARVEDOXYGEN STARVED RAPID FIRE PROGRESSIONRAPID FIRE PROGRESSION

HEAVY BLACK SMOKE TO THE FLOORHEAVY BLACK SMOKE TO THE FLOOR NO DOOR CONTROLNO DOOR CONTROL ATTACK LINE IS SHORTATTACK LINE IS SHORT ENGINE 22 OFFICER AND TRUCK 35 ENGINE 22 OFFICER AND TRUCK 35

OFFICER NEVER MEETOFFICER NEVER MEET TRUCK 35 OFFICER CONDUCTING TRUCK 35 OFFICER CONDUCTING

SEARCHSEARCH

CRITICAL FACTORSCRITICAL FACTORS STILL VENTILATION CONTROLLED FIRESTILL VENTILATION CONTROLLED FIRE

FUEL RICHFUEL RICH OXYGEN STARVEDOXYGEN STARVED RAPID FIRE PROGRESSIONRAPID FIRE PROGRESSION

HEAVY SMOKE CONDITION PERSISTSHEAVY SMOKE CONDITION PERSISTS PERSONNEL IN THE INTERIOR OF THE PERSONNEL IN THE INTERIOR OF THE

STRUCTURE WITHOUT A CHARGED STRUCTURE WITHOUT A CHARGED LINELINE ENGINE 22 ENGINE 22 TRUCK 35 TRUCK 35

22NDND ALARM SOUNDED 0444 HOURS ALARM SOUNDED 0444 HOURS

HEAVY BLACK SMOKE SHOWING FROM THE EAVES HEAVY BLACK SMOKE SHOWING FROM THE EAVES OF THE ENTIRE BUILDINGOF THE ENTIRE BUILDING

FIRE APARTMENT VENTS AT THE SLIDING GLASS FIRE APARTMENT VENTS AT THE SLIDING GLASS DOORDOOR

2213 S. Lakeshore Drive2213 S. Lakeshore Drive

AFD Recommendations AFD Recommendations from 2213 S. Lakeshorefrom 2213 S. Lakeshore

Formal Investigations indicated that AFD Formal Investigations indicated that AFD needed:needed: Change from a “policy” based system to a Change from a “policy” based system to a

“guideline” based system “guideline” based system The need to develop and review new The need to develop and review new

fireground tactics fireground tactics Additional fire ground training with an Additional fire ground training with an

emphasis on emphasis on ventilation tacticsventilation tactics and and proceduresprocedures

837 E. Oltorf Incident837 E. Oltorf Incident

Investigative Results from Investigative Results from the the

837 E. Oltorf Incident837 E. Oltorf Incident On August 22, 2003 at 02:41 Engine 6 On August 22, 2003 at 02:41 Engine 6

responded to a Heavy Box Alarm at 837 responded to a Heavy Box Alarm at 837 East Oltorf Street. Engine 6.East Oltorf Street. Engine 6.

All occupants were out of the structure. All occupants were out of the structure. The second floor fire was in a The second floor fire was in a

ventilation-controlled state with no ventilation-controlled state with no visibility and moderate to high heat (at visibility and moderate to high heat (at least 500-600least 500-600 F at waist level at the F at waist level at the doorway of fire room). doorway of fire room).


Dan Dillon IncidentDan Dillon Incident The fire attack team became separated for The fire attack team became separated for

approximately 45 seconds, the Lieutenant advancing approximately 45 seconds, the Lieutenant advancing into the bedroom on the right and the Firefighter #1 into the bedroom on the right and the Firefighter #1 proceeding down to the end of the hall. proceeding down to the end of the hall.

During this time of separation, the Engine 6 During this time of separation, the Engine 6 Lieutenant experienced a sudden and complete loss Lieutenant experienced a sudden and complete loss of air. of air.

The Engine 6 Lieutenant tried troubleshooting the The Engine 6 Lieutenant tried troubleshooting the air pack, unsuccessfully attempted to communicate air pack, unsuccessfully attempted to communicate a “Firefighter Down” and attempted to exit the a “Firefighter Down” and attempted to exit the building. The Lieutenant lost consciousness during building. The Lieutenant lost consciousness during the escape attempt and was unable to exit on his the escape attempt and was unable to exit on his own. own.

The other fire attack team member (Engine 6 The other fire attack team member (Engine 6 Firefighter #1) and Ladder 17 crew located and Firefighter #1) and Ladder 17 crew located and removed the Lieutenant from the structure.removed the Lieutenant from the structure.

2nd floor

12

31- location of dropped axe.

2 -location of voice enunciator.

3- Lt. Dillon found.

4- Fire Origin

4

Stairway Engine 6 ascended to make fire attackStairway Engine 6 ascended to make fire attackOpen door where Engine 6 LT removedOpen door where Engine 6 LT removed

Looking up attack stairwell.Looking up attack stairwell.

Looking up attack stairwellLooking up attack stairwell. .

Fire room, first door to the left (cannot see in this photo). Fire room, first door to the left (cannot see in this photo). Door at end of hall is where Engine 6 Firefighter advanced. Door at end of hall is where Engine 6 Firefighter advanced. Engine 6 LT advanced into room on the right.Engine 6 LT advanced into room on the right.

Where Engine 6 LT ran into closet door. Engine 6 LT lost Where Engine 6 LT ran into closet door. Engine 6 LT lost consciousness consciousness inside closet for 5 to 30 seconds, then regained consciousness and inside closet for 5 to 30 seconds, then regained consciousness and

collapsed in hall at end of rug in doorway. Fire room directly across hall, collapsed in hall at end of rug in doorway. Fire room directly across hall, stairway through the door just to the left.stairway through the door just to the left.

837 E. 837 E. OltorfOltorf

Point of Origin

Fire room. Window vented from the outside with pike poleFire room. Window vented from the outside with pike pole


Oltorf IncidentOltorf Incident The Engine 6 Lieutenant was transported to the The Engine 6 Lieutenant was transported to the

hospital and treated for smoke inhalation. hospital and treated for smoke inhalation. Doctor providing treatment stated that the Doctor providing treatment stated that the

Lieutenant was within 30 seconds of the injuries Lieutenant was within 30 seconds of the injuries being fatal. being fatal.

The Engine 6 Lieutenant was treated and The Engine 6 Lieutenant was treated and released the next day. Several days later the released the next day. Several days later the Engine 6 Lieutenant was readmitted to the Engine 6 Lieutenant was readmitted to the hospital and treated for chemical burns to the hospital and treated for chemical burns to the lungs. lungs.

The Engine 6 Lieutenant was released back to The Engine 6 Lieutenant was released back to active duty after three weeks and has made a active duty after three weeks and has made a full recovery. full recovery.

Issues Relevant to this Issues Relevant to this IncidentIncident

Engine 6 Lieutenant experienced a sudden and Engine 6 Lieutenant experienced a sudden and complete loss of air.complete loss of air.

Ventilation was not coordinated with fire Ventilation was not coordinated with fire attack. Engine 6 fire attack team, along with attack. Engine 6 fire attack team, along with all other crews operating on the interior, all other crews operating on the interior, entered a fire building in a ventilation-entered a fire building in a ventilation-controlled state before the structure was controlled state before the structure was effectively ventilated.effectively ventilated.

The Engine 6 fire attack team became The Engine 6 fire attack team became separated in an IDLH atmosphere while separated in an IDLH atmosphere while attempting to locate the fire. attempting to locate the fire.

Both hose team members tried to communicate Both hose team members tried to communicate via radio to announce a “Firefighter Down” and via radio to announce a “Firefighter Down” and could not locate their radio collar mics. could not locate their radio collar mics.

Formal Investigations of the Dan Formal Investigations of the Dan Dillon incident indicated that the Dillon incident indicated that the

department needed:department needed:

Continue to seek information that would assist in Continue to seek information that would assist in determining why the Engine 6 Lieutenant determining why the Engine 6 Lieutenant experienced a lost of air.experienced a lost of air.

Determine a better way of carrying the collar mics.Determine a better way of carrying the collar mics. Improve interior fire fighting communicationsImprove interior fire fighting communications Train Firefighters to solicit important information Train Firefighters to solicit important information

from occupants and witnesses.from occupants and witnesses. Share important size-up information with the entire Share important size-up information with the entire

crew.crew. Conduct Department Wide Ventilation Conduct Department Wide Ventilation

Training.Training.

Why Ventilate?Why Ventilate?

Smoke is FuelSmoke is Fuel Smoke is FuelSmoke is Fuel Smoke is FuelSmoke is Fuel Smoke is FuelSmoke is Fuel Smoke is FuelSmoke is Fuel Smoke is FuelSmoke is Fuel Smoke is FuelSmoke is Fuel

Would you fight a Would you fight a fire in a house fire in a house

filled with filled with Propane?Propane?

Propane vs. SmokePropane vs. SmokeSmoke is FuelSmoke is Fuel

PropanePropane Flammable Range Flammable Range

2.1-9.6% 2.1-9.6% Ignition Ignition

Temperature 920-Temperature 920-1120 °F1120 °F

Smoke / COSmoke / CO Flammable Range Flammable Range

12.5-74%12.5-74% Ignition Ignition

Temperature 1128 Temperature 1128 °F°F

WARNING!!!WARNING!!!When firefighters When firefighters

arrive, most fires will be arrive, most fires will be in a ventilation-in a ventilation-controlled state.controlled state.

Ventilation Controlled FiresVentilation Controlled FiresCreate Smoke that is Fuel!Create Smoke that is Fuel!

Most fires are ventilation controlled Most fires are ventilation controlled on arrival.on arrival.

Firefighter vent practices (or lack of) Firefighter vent practices (or lack of) can change a ventilation controlled can change a ventilation controlled fire to a rapid fire progression fire to a rapid fire progression (flashover,backdraft, etc.).(flashover,backdraft, etc.).

PPV can reduce the risks of PPV can reduce the risks of ventilation controlled fires when ventilation controlled fires when properly performed.properly performed.

Ventilation-ControlledVentilation-ControlledWhat does this mean?What does this mean?

A fire where the fire growth is determined A fire where the fire growth is determined by the amount of air available. A by the amount of air available. A ventilation-controlled fire occurs when ventilation-controlled fire occurs when there is not enough air to burn all the there is not enough air to burn all the materials being pyrolyzed. materials being pyrolyzed.

Less than 21% oxygen: oxygen deprived Less than 21% oxygen: oxygen deprived combustion process produces 2 to 5 times combustion process produces 2 to 5 times the amount of carbon monoxide than in a the amount of carbon monoxide than in a balanced reaction.balanced reaction.

Less than 13% oxygen: under-ventilated Less than 13% oxygen: under-ventilated fire conditions, flaming ceases, smoldering fire conditions, flaming ceases, smoldering combustion occurscombustion occurs

Ventilation-Controlled Ventilation-Controlled Compartment Fires Compartment Fires

FactsFacts High production of High production of

flammable gasesflammable gases Containment of heatContainment of heat Containment of Containment of

flammable gasesflammable gases Only needs more air Only needs more air

for the fire to for the fire to rapidly progress rapidly progress into flashover into flashover conditionsconditions

Fire poised for a Fire poised for a rapid changerapid change

Ventilation Controlled Case Ventilation Controlled Case StudiesStudies

This is an Emerging National This is an Emerging National Problem!Problem!

1.1. Washington DC under-ventilated fire Washington DC under-ventilated fire flashover kills two firefightersflashover kills two firefighters

2.2. Ohio flashover kills a firefighterOhio flashover kills a firefighter

3.3. Illinois backdraft kills two Illinois backdraft kills two firefightersfirefighters

49

UT/AFD ResearchUT/AFD Research

Using PPV to mitigate Using PPV to mitigate ventilation controlled fire ventilation controlled fire dangers in single family dangers in single family

dwellings.dwellings.

50

What Did We Know About What Did We Know About PPV?PPV?

PPV has been in existence for over 30 years.PPV has been in existence for over 30 years. Marketed as a tool to increase FF/Victim Marketed as a tool to increase FF/Victim

SafetySafety Large difference of opinions across the Fire Large difference of opinions across the Fire

Service as to its benefitsService as to its benefits Untested. Very few studies conducted on Untested. Very few studies conducted on

the cost/benefit of this tactic.the cost/benefit of this tactic. It is claimed that PPV could help reduce the It is claimed that PPV could help reduce the

chance of “extreme fire behavior” caused by chance of “extreme fire behavior” caused by fires in a ventilation controlled state. fires in a ventilation controlled state.

If misunderstood and used improperly, If misunderstood and used improperly, PPV can be harmful.PPV can be harmful.

51

AFD/UT AFD/UT Fire Tactics Research Fire Tactics Research

Group Group Recognized a lack of scientific based research in Recognized a lack of scientific based research in

ventilation tactics particularly positive pressureventilation tactics particularly positive pressure Most tactics have been based on anecdotal Most tactics have been based on anecdotal

evidenceevidence There is a great variance in opinion as to how There is a great variance in opinion as to how

positive pressure impacts a ventilation positive pressure impacts a ventilation controlled firecontrolled fire

• Firefighter safetyFirefighter safety• Victim tenability Victim tenability • Impact on fire spread/growth Impact on fire spread/growth

Very few research studies have been Very few research studies have been performed on the effects of positive pressure performed on the effects of positive pressure ventilationventilation

52

Existing StudiesExisting Studies Svensson (Swedish Rescue Services, 2001 & 2002)Svensson (Swedish Rescue Services, 2001 & 2002)

PPV increases mass burning rates PPV increases mass burning rates Temperatures increase downstream of fire and decrease upstreamTemperatures increase downstream of fire and decrease upstream Delays in attack of fire after application of PPV may induce fire spreadDelays in attack of fire after application of PPV may induce fire spread Application of Positive Pressure without Ventilation created worse Application of Positive Pressure without Ventilation created worse

conditionsconditions Ingason & Fallberg (Swedish Nat’l Testing & Research Inst., 2002)Ingason & Fallberg (Swedish Nat’l Testing & Research Inst., 2002)

Overpressures of 1-6 Pascals.Overpressures of 1-6 Pascals. Flow patterns in rooms were mapped and showed jetting flowsFlow patterns in rooms were mapped and showed jetting flows

Ziesler, Gunnerson, & Williams (Univ. of Central Florida, 1992-Ziesler, Gunnerson, & Williams (Univ. of Central Florida, 1992-1994)1994)

Primary show positive benefits of PPV (reduced temperatures, improved Primary show positive benefits of PPV (reduced temperatures, improved visibility, no spread of heat)visibility, no spread of heat)

National Research Council of Canada (2002, high-rise buildings)National Research Council of Canada (2002, high-rise buildings) Technical Research Center of Finland (VTT) (2000)Technical Research Center of Finland (VTT) (2000) Walton and Kerber (NIST/BFRL) Walton and Kerber (NIST/BFRL)

PPV fan flows have been characterized; Effects on heat release rate are PPV fan flows have been characterized; Effects on heat release rate are documented.documented.

UT/AFD (2002-present)UT/AFD (2002-present) Effects of vent location; cold flows in multiple story buildings; effects of Effects of vent location; cold flows in multiple story buildings; effects of

leakagesleakages

53

Context of the Study Context of the Study What type of building are we testing?What type of building are we testing?

• Single family dwellings (Hot Tests)Single family dwellings (Hot Tests)• Multi-story structure (Cold Flow Tests)Multi-story structure (Cold Flow Tests)• Burn structure cold and hot testsBurn structure cold and hot tests

Test VariablesTest Variables• Vent opening locationVent opening location• PPV fan configuration (CFM rating)PPV fan configuration (CFM rating)• Natural vs. PPV ventilationNatural vs. PPV ventilation• Balloon frame flowsBalloon frame flows

What are the effects of Positive Pressure on:What are the effects of Positive Pressure on:• Victim survivability in relation to the Victim survivability in relation to the

ventilation/attack corridor ventilation/attack corridor • Fireground conditionsFireground conditions

Current Positive Pressure Studies

54

Single Story House Single Story House LayoutLayout

Fire Victim

A

B

C

D

E F

Fan

14.5 m

3.8 m3.0 m7.7 m

4.4 m

3.9 m

4.4 m

4.4 m

5.4 m 2.6 m

dr1

dr2

dr3

dr4

wd1 wd2

55

Fire RoomFire Room

Fire room Fire room hardened by hardened by adding more adding more sheet rocksheet rock

56

Fire Room ExteriorFire Room Exterior

Cut ports for videoCut ports for video

Install vent Install vent opening system: opening system: “Articulated Flying “Articulated Flying Buttress”.Buttress”.

57

Victim RoomVictim Room

Cut holes for Cut holes for camerascameras

Remove windows Remove windows and replace with and replace with plywoodplywood

Cover closet to Cover closet to simplify modelingsimplify modeling

Insert DummyInsert Dummy

58

TemperatureTemperature

40 channels of 40 channels of type K type K thermocouples thermocouples were used.were used.

All signals taken All signals taken from exterior of from exterior of house to data house to data shed.shed.

Multiple burns damage gypsum

59

Data AcquisitionData Acquisition

Data acquired by Data acquired by computer.computer.

Video and Infrared Video and Infrared moviesmovies

Rocket Scientist

60

FuelFuel

12 Polyurethane 12 Polyurethane foam pads.foam pads.

Fuel load Fuel load approximates total approximates total heat release of heat release of heavily loaded room heavily loaded room contents fire (2.4 contents fire (2.4 MW).MW).

61

Air FlowAir Flow

Two Fans used:Two Fans used:

an 18” and a 24”an 18” and a 24”

18”: 6500 CFM18”: 6500 CFM

24”: 9130 CFM24”: 9130 CFM

Fan placed at attack Fan placed at attack entrance: typically entrance: typically placed at the front placed at the front door of the housedoor of the house

62

Live Fire VideoLive Fire Video

Hallway

Vent Window

Victim Room(video camera)

Victim Room(TIC)

PPV Victim Room Vent

63

Live Fire VideoLive Fire Video

Hallway

Vent Window

Victim Room(video camera)

StagingRoom(TIC)

65

Scientific Scientific Principles and Principles and Results of the Results of the

ResearchResearchNot Tactics!Not Tactics!

66

Physics of PPVPhysics of PPV How does PPV work? How does PPV work?

The heat layer affects rapid fire The heat layer affects rapid fire progressionprogression

Pressure created by PPVPressure created by PPV

(Is "positive pressure” a correct term?)(Is "positive pressure” a correct term?) Fan characteristics (Fan is a Pump)Fan characteristics (Fan is a Pump) Typical house flow resistances (Friction Typical house flow resistances (Friction

Loss)Loss) Trade-offs in applying PPVTrade-offs in applying PPV

67

How heat layer effects rapid How heat layer effects rapid fire progression.fire progression.

Heat feedback

There is a competition between heat release rate and heat losses. Heat release rate is tied to the heat feedback. Heat losses can be tied to the convection of the hot upper layer out of the compartment.

To prevent rapid fire progression, take away the heat feedback and increase the heat losses by blowing the products out of a vent.

68

Fire Dynamics 101Fire Dynamics 101

T

time

flashover

fully developed fire

decay

ignition

growth

< 2 mins

1500 oF or 815 oC

Fires are generally modeled as having three distinctive phases:

growth phase, fully developed phase and decay phase.

Naturalventing

69

PPV

time

Avg. Temp.

Burn Rate

PPV pushes the heat layer out and decreases the average temperature even when the burning rate increases

70

Review #1Review #1When Fire is Ventilation When Fire is Ventilation

Controlled:Controlled: This is when firefighters normally This is when firefighters normally

arrive.arrive. Heavy smoke is produced creating Heavy smoke is produced creating

limited visibility.limited visibility. The heat layer increases off gassing The heat layer increases off gassing

(CO) faster than the fire itself.(CO) faster than the fire itself. Conditions poised to change rapidly.Conditions poised to change rapidly. Venting the hot products makes entry Venting the hot products makes entry

safer. safer.

71

How Does PPV Work?How Does PPV Work?•PPV uses a fan (positive pressure source) to exhaust smoke, flammable gases, and high temperature gases from a structure fire.

•The fan characteristics (pump) and the resistance network (friction loss) will determine the flow characteristics.

•The flow at the fire compartment determines if PPV is a net positive or negative.

•Big flow good, small flow could be bad.

72

Swedish StudiesSwedish Studies

Swedish study of Ingason and Fallberg Swedish study of Ingason and Fallberg measured static pressures and flow measured static pressures and flow patternspatterns

PPV produces pressures less than PPV produces pressures less than 1/1001/100thth of 1 PSI of 1 PSI

Flow velocities and patterns show Flow velocities and patterns show jet like jet like regionsregions (Jet Stream) with secondary flows (Jet Stream) with secondary flows (recirculation regions).(recirculation regions).

Velocities are typically in Velocities are typically in 2.2 mph to 2.2 mph to 8.8 mph8.8 mph range. range.

73

Computer Modeling of Computer Modeling of FireFire

The newest way to understand fire The newest way to understand fire physics is through the use of computer physics is through the use of computer simulations.simulations.

A powerful modeling tool is Fire A powerful modeling tool is Fire Dynamics Simulator (FDS) developed by Dynamics Simulator (FDS) developed by NIST.NIST.

Great care must be taken in the use of Great care must be taken in the use of computer models to understand fire computer models to understand fire since we all know that garbage in = since we all know that garbage in = garbage out!garbage out!

74

Cold Flow Contours of Air Speed

Fire Room Vented

•PPV does not “pressurize” the entire structure•PPV develops a “Jet Stream” from the entrance to

the exit opening.

CLOSED

CLOSED

CLOSED

OPEN

OPEN

OPEN

75

Cold Flow Contours of Air Speed

Fire Room Vented

•PPV does not “pressurize” the entire structure•PPV develops a “Jet Stream” from the entrance to

the exit opening.

Fire corridor- All of the compartments that contain fire or are connected to the fire room though open

doorways.

CLOSED

CLOSED

CLOSED

OPEN

OPEN

OPEN

76

House Layout & Friction House Layout & Friction LossLoss

fire

victim

4.1 m

4.1 m

4.1 m

3.35 m

1.5 m 3.35 m

A

A

77


fire

victim

4.1 m

4.1 m

4.1 m

3.35 m

1.5 m 3.35 m

A

A

•PPV uses a fan (positive pressure source) to exhaust smoke, flammable gases, and high temperature gases from a structure fire.

78


fire

victim

4.1 m

4.1 m

4.1 m

3.35 m

1.5 m 3.35 m

A

A

•PPV uses a fan (positive pressure source) to exhaust smoke, flammable gases, and high temperature gases from a structure fire.•The fan characteristics (pump) and the resistance network (friction loss) will determine the flow characteristics.•The windows can be thought of as the “nozzles”

79


fire

victim

4.1 m

4.1 m

4.1 m

3.35 m

1.5 m 3.35 m

A

A

•PPV uses a fan (positive pressure source) to exhaust smoke, flammable gases, and high temperature gases from a structure fire.•The fan characteristics (pump) and the resistance network (friction loss) will determine the flow characteristics.•The flow rate at the fire compartment determines if PPV is a net positive or negative.


80


fire

victim

4.1 m

4.1 m

4.1 m

3.35 m

1.5 m 3.35 m

A

A

•PPV uses a fan (positive pressure source) to exhaust smoke, flammable gases, and high temperature gases from a structure fire.•The fan characteristics (pump) and the resistance network (friction loss) will determine the flow characteristics.•The flow rate at the fire compartment determines if PPV is a net positive or negative.


81

Review #2Review #2 PPV creates very little pressure, normally PPV creates very little pressure, normally

just a fraction of a PSI.just a fraction of a PSI. Instead of pressurizing the entire building, Instead of pressurizing the entire building,

the fan creates a “Jet Stream” from the fan creates a “Jet Stream” from entrance to exit.entrance to exit.

A fan is like a pump - A fire is like a pump.A fan is like a pump - A fire is like a pump. Opening too many windows can cause Opening too many windows can cause

small flow.small flow. Big flow is good, small flow could be bad.Big flow is good, small flow could be bad. PPV overcoming winds: Vendors say 35 PPV overcoming winds: Vendors say 35

MPH, but Tests show 8.8 MPH.MPH, but Tests show 8.8 MPH.

82

Trade-offs in Applying Trade-offs in Applying PPVPPV

BenefitsBenefits Clears attack corridor of smoke, gases, and Clears attack corridor of smoke, gases, and

high temperatureshigh temperatures Less likely extreme fire behaviorLess likely extreme fire behavior Faster path to fire compartmentFaster path to fire compartment Safer attack scenariosSafer attack scenarios

CostsCosts Possible spread of fire to non-connected areas.Possible spread of fire to non-connected areas. Possible increase in burning rate of firePossible increase in burning rate of fire Possible hazard to victims downstream of Possible hazard to victims downstream of

ventilation pathventilation path

83

PPV in HousePPV in House

Detailed simulations were performed for the entire house to

examine the effect of ventilation on a

victim room.

Fire Victim

A

B

C

D

E F

Fan

14.5 m

3.8 m3.0 m7.7 m

4.4 m

3.9 m

4.4 m

4.4 m

5.4 m 2.6 m

dr1

dr2

dr3

dr4

wd1 wd2

84

Natural Burn Fire Room Natural Burn Fire Room SlicesSlices

Temperature and velocity

vector plots in the fire room

without venting

Roll-up vortices are

clearly identifiable

victim room

fire room

victim room

fire room

No visible mixing in victim room

85

victim room

Effects of fire room venting and positive pressure on velocity vectors is clearly seen in:

Figure (a) prior to venting (40 seconds)

Figure (b) at initiation of venting (80 seconds)

Figure (c) during PPV (120 seconds)

(a)

(b)

(c)

Notice the increased mixing in the fire room

86

victim room

Effects of fire room venting and positive pressure on velocity vectors is clearly seen in:




(a)

(b)

(c)

Notice the increased mixing in the fire room

No visible mixing in victim room

87

Effects of victim room venting and positive pressure on velocity vectors is clearly seen in:




(a)

(b)

(c)

Notice the increased mixing in the victim room

victim room

88

Effects of victim room venting and positive pressure on velocity vectors is clearly seen in:




(a)

(b)

(c)

Notice the increased mixing in the victim room

victim room

Visible Mixing is victim room

89

FDS Models of FDS Models of Platt Road HousePlatt Road House

Examining Temperature in Examining Temperature in the hallway for a vented fire the hallway for a vented fire

room versus a vented fire room versus a vented fire room with PPVroom with PPV

90

Hallway Temperature – Hallway Temperature – 20s20s

Natural Vent (Top) PPV (Bottom)

91


Attack direction

92


93


94


95


PPV Fan turned on.

96


97


98


Note cooler attack path for PPV case (bottom)

99

ReviewReview Correctly Venting Fire RoomCorrectly Venting Fire Room

Vent as close to the fire as possibleVent as close to the fire as possible PPV is more effective than natural PPV is more effective than natural

horizontal ventilation horizontal ventilation Temperature slightly increases with Temperature slightly increases with

natural ventilation at victim levelnatural ventilation at victim level Temperatures reduce with PPV at Temperatures reduce with PPV at

victim levelvictim level Incorrectly Venting Victim Room Incorrectly Venting Victim Room

Victims downwind of the PPV do Victims downwind of the PPV do experience an increase in temperature but experience an increase in temperature but the increase is small, survivable and the increase is small, survivable and temporarytemporary

Tactical Tactical Application of Application of

Scientific ResultsScientific Results

Ventilation can be Ventilation can be ConfusingConfusing

Positive Pressure VentilationPositive Pressure Ventilation Negative Pressure VentilationNegative Pressure Ventilation Horizontal VentilationHorizontal Ventilation Vertical VentilationVertical Ventilation Mechanical VentilationMechanical Ventilation Natural VentilationNatural Ventilation Hydraulic VentilationHydraulic Ventilation Vent for Life, Vent for FireVent for Life, Vent for Fire

Vertical Ventilation is the Vertical Ventilation is the Most Effective Form of Most Effective Form of

Ventilation If…Ventilation If… It can be performed safelyIt can be performed safely It can be performed in a timely It can be performed in a timely

mannermanner Vertical Ventilation should be Vertical Ventilation should be

strongly considered on:strongly considered on: Heavily smoke charged, larger, Heavily smoke charged, larger,

commercial structurescommercial structures Heavily involved balloon framed Heavily involved balloon framed

structuresstructures

If Vertical Ventilation is If Vertical Ventilation is Not PerformedNot Performed

UT/AFD have conducted 3 full scale UT/AFD have conducted 3 full scale tests on PPV and has conducted tests on PPV and has conducted continuous PPV research for the last 5 continuous PPV research for the last 5 years. years.

UT/AFD studies prove that horizontal UT/AFD studies prove that horizontal ventilation with PPV at single family ventilation with PPV at single family dwelling fires is effectivedwelling fires is effective

Firefighters must know how and why to Firefighters must know how and why to employ horizontal PPV tactics correctlyemploy horizontal PPV tactics correctly

Ventilation ReasonsVentilation Reasons Vent for Fire: Venting to assist the Vent for Fire: Venting to assist the

fire attack effortfire attack effort Vent For Life: Venting as you Vent For Life: Venting as you

search– improves Firefighter search– improves Firefighter safety and reduces thermal and safety and reduces thermal and toxic damage to victims.toxic damage to victims.

How can we perform both of these How can we perform both of these ventilation tactics with PPV?ventilation tactics with PPV?

Vent for Fire, Vent for Vent for Fire, Vent for LifeLife

Think of the fire building as a series Think of the fire building as a series of compartments that can be of compartments that can be separated or connected by the separated or connected by the existing doors.existing doors.

Fire corridorFire corridor- All of the - All of the compartments that either contain compartments that either contain fire or are connected to the fire fire or are connected to the fire room though open doorways. room though open doorways.

Fire Corridor

Outside of Fire Corridor

CLOSED

CLOSED

CLOSED OPEN

OPEN

OPEN

Properly Venting for FireProperly Venting for Fire Coordinated Fire Attack SOG (90/10 Coordinated Fire Attack SOG (90/10

rule)rule) Hot Lap and VentilationHot Lap and Ventilation

Locate Fire – Determine RiskLocate Fire – Determine Risk Determine Vent Opening Location, close Determine Vent Opening Location, close

to fireto fire Determine when to make vent – Determine when to make vent –

Coordinate; Do not vent until attack Coordinate; Do not vent until attack crew is ready to entercrew is ready to enter

Fire AttackFire Attack Employ PPV before entryEmploy PPV before entry Observe effectsObserve effects Make Fire AttackMake Fire Attack

Properly Venting for FireProperly Venting for Fire

Other Tactical FunctionsOther Tactical Functions Must ensure “Vent for Life”, Laddering Must ensure “Vent for Life”, Laddering

and/or Additional Forcible Entry do not and/or Additional Forcible Entry do not negatively affect ventilationnegatively affect ventilation

The coordination of ventilation The coordination of ventilation activities should becomes the context activities should becomes the context for all fireground tactical activities. for all fireground tactical activities.

Ventilation: Context for Ventilation: Context for TacticsTactics

11stst in Engine Officer – in Engine Officer – Locate fire room, Coordinate opening vents with Locate fire room, Coordinate opening vents with

attack team readinessattack team readiness Open up all possible fire room vents. Open up all possible fire room vents.

Outside Team MonitorOutside Team Monitor During the Officer hot lap, look under smoke/heat During the Officer hot lap, look under smoke/heat

layer in first room for victims.layer in first room for victims. Place fan correct distance from door (6-10 feet).Place fan correct distance from door (6-10 feet). Ensure fan is at correct position and angle.Ensure fan is at correct position and angle. Stay out of “jet Stream” as much as practicalStay out of “jet Stream” as much as practical Monitor vent exit to ensure ventilation Monitor vent exit to ensure ventilation

effectiveness.effectiveness.

Ventilation: Context for Ventilation: Context for TacticsTactics

Backup Team: Backup Team: Close doors Close doors Stay out of “jet Stream” as much as practicalStay out of “jet Stream” as much as practical

Inside Truck:Inside Truck: Maintain fire corridor integrity by shutting doorsMaintain fire corridor integrity by shutting doors Ensure that search for fire extension activates Ensure that search for fire extension activates

have minimum impact on fire corridor integrity have minimum impact on fire corridor integrity Outside Truck: Outside Truck:

Coordinate VES (if used). Coordinate VES (if used). Ensure forcible entry does not negatively effect Ensure forcible entry does not negatively effect

fire corridor integrityfire corridor integrity Check soffit for exposure near fire room vent Check soffit for exposure near fire room vent

openingopening Laddering Laddering

Vent or Search?Vent or Search?

Many times, first arriving crews are Many times, first arriving crews are faced with competing priorities.faced with competing priorities.

Knowing what to start first and what Knowing what to start first and what to leave out is an extremely difficult to leave out is an extremely difficult choice, especially when a victim’s choice, especially when a victim’s life may be at stake.life may be at stake.

Which choice gives the victim the Which choice gives the victim the best chance for survival? best chance for survival?

Vent or Search?Vent or Search?

There is no possible right answer that will There is no possible right answer that will fit every situation.fit every situation.

How close the next crew is to arriving How close the next crew is to arriving may affect this decisionmay affect this decision

If a very reliable source is giving you If a very reliable source is giving you victim location from, it may be best to victim location from, it may be best to search before ventilation. search before ventilation.

If you are less sure of victim location, If you are less sure of victim location, venting may increase your overall search venting may increase your overall search speed speed

Vent or Search?Vent or Search? Vent 1Vent 1stst

AdvantagesAdvantages Time used venting can Time used venting can

be made up quickly be made up quickly after ventilation beginsafter ventilation begins

Once victim is found, Once victim is found, environment may be environment may be better for survivalbetter for survival

Disadvantages:Disadvantages: Search may be delayed Search may be delayed

30-60 seconds while 30-60 seconds while ventilation is being set ventilation is being set upup

Search 1Search 1stst

AdvantagesAdvantages Could locate victim Could locate victim

faster if victim located faster if victim located very early onvery early on

Disadvantages:Disadvantages: If victim is not located If victim is not located

early, overall search early, overall search speed is reducedspeed is reduced

Increased risk to FF’s Increased risk to FF’s

Vent or Search Vent or Search Comparison Comparison

Chance of Victim Survival

Time

Ch

ance

of

Su

rviv

al /

L

oca

tio

n S

uce

ss Chance of VictimSurvival

Search 1st - Chance ofVictim Location

Vent 1st - Chance ofVictim Location

All Fire Tactics Should Be All Fire Tactics Should Be Selected, Assessed and, if Selected, Assessed and, if

necessary, Altered.necessary, Altered. A tactic should not be selected routinely, A tactic should not be selected routinely,

rather should be selected to solve the rather should be selected to solve the problems the fire is presenting.problems the fire is presenting.

After selected, the tactic should be After selected, the tactic should be assessed for effectiveness.assessed for effectiveness.

The tactic should be changed if it proves The tactic should be changed if it proves to be ineffective.to be ineffective.

How Can The Effectiveness How Can The Effectiveness Of PPV Be Assessed?Of PPV Be Assessed?

After PPV is applied to the entrance of the After PPV is applied to the entrance of the attack corridor, observe the direction of the attack corridor, observe the direction of the smoke flow.smoke flow.

If the smoke flow is toward the fire room vent If the smoke flow is toward the fire room vent opening, PPV is effective.opening, PPV is effective. Prevailing winds are not overcoming fan.Prevailing winds are not overcoming fan. Added oxygen is not increasing burning rate Added oxygen is not increasing burning rate

enough to create ceiling jet.enough to create ceiling jet. There is a clear path from entrance to vent exit. There is a clear path from entrance to vent exit.

Continually observe smoke flows as you Continually observe smoke flows as you advance down the attack corridor.advance down the attack corridor.

How Can The Effectiveness How Can The Effectiveness Of PPV Be Assessed?Of PPV Be Assessed?

If the smoke and fire gases are still If the smoke and fire gases are still moving towards you:moving towards you: Prevailing winds may be overcoming Prevailing winds may be overcoming

the fan, possibly making the entrance the fan, possibly making the entrance corridor unsafe for entry.corridor unsafe for entry.

Fire behavior may have rapidly Fire behavior may have rapidly increased, making entry risky.increased, making entry risky.

A change of tactics may be required.A change of tactics may be required.

Rules for Effective PPVRules for Effective PPV MustMust have an exit before positive pressure is have an exit before positive pressure is

appliedapplied MustMust have attack corridor integrity. Too many have attack corridor integrity. Too many

vent exits can adversely effect PPV vent exits can adversely effect PPV effectivenesseffectiveness

ShouldShould know the fire location and make the know the fire location and make the exit vent as close to the fire as possibleexit vent as close to the fire as possible

MustMust account for wind direction and speedaccount for wind direction and speed MustMust assess direction of smoke flow in the fire assess direction of smoke flow in the fire

attack corridor to assess effectiveness of PPV.attack corridor to assess effectiveness of PPV. NeverNever direct a hose stream into the exit vent direct a hose stream into the exit vent

Benefits of Effective PPVBenefits of Effective PPV

Heat and smoke are removed before the Heat and smoke are removed before the firefighters enter the areafirefighters enter the area

The chance of rapid fire progression due to The chance of rapid fire progression due to ventilation-controlled fire is reducedventilation-controlled fire is reduced

The officer knows the location of the fire The officer knows the location of the fire and the layout of the buildingand the layout of the building

Visibility is improvedVisibility is improved Search can be performed faster and more Search can be performed faster and more

safelysafely In general, Firefighter safety is enhanced.In general, Firefighter safety is enhanced.

WRONG! WRONG! FAN

FAN

Coordinated Ventilation

Venting for LifeVenting for Life

Breaking windows in the fire corridor Breaking windows in the fire corridor will affect (either positively and will affect (either positively and negatively) ventilation conditions.negatively) ventilation conditions.

Research from the UT/AFD PPV Research from the UT/AFD PPV studies indicates that, all things being studies indicates that, all things being equal, small pressure differences equal, small pressure differences caused by breaking a window in a caused by breaking a window in a fire fire corridorcorridor causes the smoke and heat causes the smoke and heat to start moving in that direction.to start moving in that direction.

Venting for LifeVenting for Life Therefore, if while searching you Therefore, if while searching you

remove a window in the fire remove a window in the fire corridor to release heat and corridor to release heat and smoke to improve your conditions smoke to improve your conditions (Vent for Life), the opposite effect (Vent for Life), the opposite effect may be realized.may be realized.

Many Firefighters that were killed Many Firefighters that were killed or injured in extreme fire behavior or injured in extreme fire behavior were killed in an event that was were killed in an event that was caused by their own ventilation caused by their own ventilation practices! practices!

CLOSED

CLOSED

CLOSED OPEN

OPEN

OPEN

Fire Corridor

CLOSED

CLOSED

CLOSED OPEN

OPEN

OPEN

Fire Corridor

Outside of Fire Corridor

Tenable Victim Locations

CLOSED

CLOSED

CLOSED OPEN

OPEN

OPEN

Properly Venting for LifeProperly Venting for Life Separate a compartment from the fire Separate a compartment from the fire

corridor by closing a door (door corridor by closing a door (door control).control).

Now the heat layer is no longer Now the heat layer is no longer racing into the room and windows racing into the room and windows can be safely removed, if necessarycan be safely removed, if necessary

All crews operating inside should All crews operating inside should close doors as they go (if possible) to close doors as they go (if possible) to ensure fire corridor integrity. ensure fire corridor integrity.

Properly Venting for LifeProperly Venting for Life

Break or open windows… If you Break or open windows… If you cannot see your exit, break the cannot see your exit, break the window! Your life is more valuable window! Your life is more valuable than a window.than a window.

When leaving the room, the door When leaving the room, the door should remain shut. should remain shut.

This will ensure that “vent for life” This will ensure that “vent for life” actions do not effect ventilation actions do not effect ventilation efforts in the efforts in the fire corridor.fire corridor.

FAN


WRONG! WRONG! Door OpenDoor Open

FAN

FAN


Door Closed

Benefits of Venting for Benefits of Venting for LifeLife

Creates an environment safer for Creates an environment safer for both the victims and searchers.both the victims and searchers. Increases visibility and improves victim Increases visibility and improves victim

tenabilitytenability Allows for secondary egressAllows for secondary egress By looking out the window, searches By looking out the window, searches

can re-orient themselves can re-orient themselves Indicates to the Outside Truck / RIC Indicates to the Outside Truck / RIC

their locationtheir location

Wind considerations?Wind considerations?

Will prevailing winds affect your Will prevailing winds affect your ability to ventilate a building using ability to ventilate a building using Positive Pressure Ventilation?Positive Pressure Ventilation?

Wind considerations?Wind considerations?

If you cannot vent because of If you cannot vent because of prevailing wind conditionsprevailing wind conditions Use another windowUse another window

oror Do not ventDo not vent

oror Vent for positionVent for position

Importance of starting PPV Importance of starting PPV beforebefore making entry making entry

When performed properly, PPV can When performed properly, PPV can have a dramatic effect on the firehave a dramatic effect on the fire

Basically, PPV rapidly forces a Basically, PPV rapidly forces a ventilation controlled fire back to a ventilation controlled fire back to a free burning (fuel controlled) fire.free burning (fuel controlled) fire.

The behavior of a free-burning fire is The behavior of a free-burning fire is much more predictablemuch more predictable


You do not want Firefighters inside during this transition! If You do not want Firefighters inside during this transition! If something is to go wrong, now is the most likely time.something is to go wrong, now is the most likely time.

T

time

flashover

fully developed fire

decay

ignition

growth

< 2 mins

1500 oF or 815 oC


Ventilation at 2seconds, The greenregion shows an area ofdanger as fire gases mix with incoming air toform a flammable layer


Just 10 seconds after the venting action occurs,a clear flammablelayer (green) exists nearthe ceiling. This situationcould possibly lead to a’rollover,’ if there is anignition source available

Other PPV UsesOther PPV Uses We have discussed PPV used during an We have discussed PPV used during an

offensive fire attack to mitigate the effects offensive fire attack to mitigate the effects of ventilation controlled fires.of ventilation controlled fires.

Other Possible Uses for PPVOther Possible Uses for PPV Use during investigative mode to assist in Use during investigative mode to assist in

locating the firelocating the fire Use PPV to assist in overhaul, post fire knock-Use PPV to assist in overhaul, post fire knock-

downdown Venting for tactical positionVenting for tactical position Use of PPV Use of PPV outsideoutside the fire corridor for the fire corridor for

Attic FiresAttic Fires Uninvolved adjacent structuresUninvolved adjacent structures

PPV Use During PPV Use During Investigative Mode to Assist Investigative Mode to Assist

in Locating Firein Locating Fire Situation: Structure filled with Situation: Structure filled with

smoke. The smoke is moving slowly smoke. The smoke is moving slowly (low pressure/ velocity). Fire (low pressure/ velocity). Fire location is not evident. Fire could be location is not evident. Fire could be in void spaces. In the occupied area in void spaces. In the occupied area of the building, the fire is not in a of the building, the fire is not in a ventilation controlled state.ventilation controlled state.


in Locating Fire in Locating Fire Possible Tactical Considerations:Possible Tactical Considerations:

Do not want to spread fire by running fan Do not want to spread fire by running fan unregulatedunregulated

If available, consider selecting an opening that If available, consider selecting an opening that could be later shut (window, sliding glass door)could be later shut (window, sliding glass door)

Run fan long enough to remove smoke and then Run fan long enough to remove smoke and then remove fan (turn to the side and throttle down). remove fan (turn to the side and throttle down).

If fire location is not now evident, look for If fire location is not now evident, look for smoke seepage. Smoke seepage can be hard to smoke seepage. Smoke seepage can be hard to recognize when fan is running.recognize when fan is running.

Open up as necessary. Open up as necessary.


in Locating Fire in Locating Fire If visibility becomes poor again, run fan long If visibility becomes poor again, run fan long

enough to remove smoke and then remove fan enough to remove smoke and then remove fan (turn to the side and throttle down). (turn to the side and throttle down).

Repeat as necessary Repeat as necessary This starting and stopping of the fan allows you This starting and stopping of the fan allows you

to clear the smoke making it easier to locate to clear the smoke making it easier to locate fire but reduces the change of increasing fire fire but reduces the change of increasing fire spread in the void spaces.spread in the void spaces.

ImportantImportant: If fan is started with no vent : If fan is started with no vent opening, void spaces will become pressurized opening, void spaces will become pressurized and fire located in the void spaces may be and fire located in the void spaces may be increased.increased.

Use of PPV to Assist in Use of PPV to Assist in Overhaul, Post Fire Knock-Overhaul, Post Fire Knock-

DownDown Very similar in principal to PPV use Very similar in principal to PPV use

during investigative mode to assist in during investigative mode to assist in locating the fire locating the fire

There have been many cases There have been many cases nationally of a fan being left running nationally of a fan being left running after fire knockdown and a rekindle after fire knockdown and a rekindle then destroying the structure.then destroying the structure. Although these cases are caused by Although these cases are caused by

improper use of the fan, some firefighters improper use of the fan, some firefighters will use it as a justification for never will use it as a justification for never using PPV. using PPV.


DownDown Possible Tactical Considerations:Possible Tactical Considerations:

Use same vent opening used to vent fire Use same vent opening used to vent fire room when possibleroom when possible

Run fan long enough to remove smoke Run fan long enough to remove smoke and then remove fan (turn to the side and then remove fan (turn to the side and throttle down). and throttle down).

Look for smoke seepage. Smoke seepage Look for smoke seepage. Smoke seepage can be hard to recognize when fan is can be hard to recognize when fan is running.running.

Open up as necessary. Open up as necessary.


DownDown If visibility become poor again, run fan long If visibility become poor again, run fan long

enough to remove smoke and then remove fan enough to remove smoke and then remove fan (turn to the side and throttle down). (turn to the side and throttle down).

Repeat as necessary Repeat as necessary This starting and stopping of the fan allows you This starting and stopping of the fan allows you

to clear the smoke making it easier to locate to clear the smoke making it easier to locate hidden fire during overhaul but reduces the hidden fire during overhaul but reduces the change of increasing fire spread in the void change of increasing fire spread in the void spaces.spaces.

ImportantImportant: If fan is started with no vent opening, : If fan is started with no vent opening, void spaces will become pressurized and fire void spaces will become pressurized and fire located in the void spaces may be increased.located in the void spaces may be increased.

Venting for Tactical Venting for Tactical PositionPosition

Sometimes, even if you know fire Sometimes, even if you know fire location, ventilation of the fire room location, ventilation of the fire room may not be possible.may not be possible. In multi-story structures, window(s) for In multi-story structures, window(s) for

venting may be out of reachventing may be out of reach Obstacles such as fences, dogs, or Obstacles such as fences, dogs, or

anything else may prevent ventilationanything else may prevent ventilation The building may have solids walls with no The building may have solids walls with no

windows or other opening in the fire area. windows or other opening in the fire area. Wind direction/velocity may prevent Wind direction/velocity may prevent

ventingventing


Possible Tactical Considerations:Possible Tactical Considerations: If you have a high confidence of fire If you have a high confidence of fire

location but cannot vent the fire room:location but cannot vent the fire room: Locate vent opening between fire and entrance Locate vent opening between fire and entrance Start PPV, jet stream should clear smoke path Start PPV, jet stream should clear smoke path

between entrance and exit making entry safer between entrance and exit making entry safer than attacking under heated, smoky conditionsthan attacking under heated, smoky conditions

Advance closer to the fire area trying to stay Advance closer to the fire area trying to stay within the fan jet stream as much as possiblewithin the fan jet stream as much as possible

PPV use PPV use OutsideOutside the Fire the Fire CorridorCorridor

The fire compartment is pressurized by the The fire compartment is pressurized by the fire itself and can start seeping to other fire itself and can start seeping to other compartments outside the fire corridorcompartments outside the fire corridor

Compartments outside the fire corridor can Compartments outside the fire corridor can become charged with smoke through become charged with smoke through seepage. seepage.

This can happen in:This can happen in: Attic Fires (smoke seeping from attic to occupied Attic Fires (smoke seeping from attic to occupied

space) space) Uninvolved adjacent structures or compartmentsUninvolved adjacent structures or compartments

PPV use PPV use OutsideOutside the Fire the Fire Corridor:Corridor:

Attic FiresAttic Fires Possible Tactical Considerations:Possible Tactical Considerations:

If fire is contained to attic on arrival, smoke If fire is contained to attic on arrival, smoke conditions in conditions in occupied spacesoccupied spaces will be from will be from seepage. This should be easily recognizable seepage. This should be easily recognizable by lower temperatures and smoke character by lower temperatures and smoke character (speed, density).(speed, density).

If attack crews pull ceiling to attack fire If attack crews pull ceiling to attack fire BEFORE pressurizing structure, the fire BEFORE pressurizing structure, the fire products from the attic will enter the products from the attic will enter the occupied space .occupied space .


Attic FiresAttic Fires Possible Tactical Considerations:Possible Tactical Considerations:

If time allows, If time allows, beforebefore pulling ceiling to attack pulling ceiling to attack fire, create additional ventilation opens in attic.fire, create additional ventilation opens in attic.

This can usually be quickly accomplished by This can usually be quickly accomplished by opening up eve vents or gable vents where opening up eve vents or gable vents where smoke is exiting (if available) or possibly by smoke is exiting (if available) or possibly by performing vertical ventilation.performing vertical ventilation.

Structure can be pressurized while the attic exit Structure can be pressurized while the attic exit opening is being made. This may prevent opening is being made. This may prevent additional seepage into the occupied areas.additional seepage into the occupied areas.

Place salvage covers if time allowsPlace salvage covers if time allows After the attic is effectively ventilated, ensure fan After the attic is effectively ventilated, ensure fan

is properly placed and running at the entrance is properly placed and running at the entrance area before pulling ceiling to attack fire.area before pulling ceiling to attack fire.


Pressurization of adjacent spacesPressurization of adjacent spaces Much like the attic fire described before, Much like the attic fire described before,

areas outside the fire corridor, such as areas outside the fire corridor, such as adjacent occupancies in strip malls, can adjacent occupancies in strip malls, can begin to fill with smoke through seepage.begin to fill with smoke through seepage.

If your crew is assigned to protect an If your crew is assigned to protect an adjacent occupancy, pressurizing the adjacent occupancy, pressurizing the adjacent occupancy could help to reduce adjacent occupancy could help to reduce the seepage into this area thus increasing the seepage into this area thus increasing your visibility and possibly reducing smoke your visibility and possibly reducing smoke damage.damage.

Pressurization of Pressurization of adjacent spacesadjacent spaces

Space on fire

Adjacent space

Purpose: to prevent the spread of smoke and hot gases to adjacent spaces


Pressurization of adjacent spacesPressurization of adjacent spaces Possible Tactical Considerations:Possible Tactical Considerations:

If filled with smoke, initially start fan and If filled with smoke, initially start fan and open vent opposite the fan side of the open vent opposite the fan side of the adjacent property which you are trying to adjacent property which you are trying to protect.protect.

After smoke is clear, close vent. This should After smoke is clear, close vent. This should pressurize the structure and help to prevent pressurize the structure and help to prevent further seeping of smoke into the adjacent further seeping of smoke into the adjacent structure.structure.

Closely monitor the effects of your ventilation Closely monitor the effects of your ventilation efforts and make adjustments as necessary. efforts and make adjustments as necessary.

Final ReviewFinal Review

Final ReviewFinal Review Understand the dangers of Understand the dangers of

Ventilation Controlled Fires.Ventilation Controlled Fires. A ventilation controlled fire creates A ventilation controlled fire creates

smoke that is fuelsmoke that is fuel This smoke can cause rapid fire This smoke can cause rapid fire

progressionprogression This smoke can cause zero visibilityThis smoke can cause zero visibility Rapid fire progression and zero Rapid fire progression and zero

visibility can kill firefightersvisibility can kill firefighters

Final ReviewFinal Review Given the coordination of all Given the coordination of all

company actions on the fireground company actions on the fireground needed to ventilate effectively and needed to ventilate effectively and safety, ventilation becomes the safety, ventilation becomes the context for the development of context for the development of tactical decisions and on-scene tactical decisions and on-scene actions.actions.

Final ReviewFinal Review Understand the importance of Understand the importance of

proper ventilation.proper ventilation. Proper ventilation can reduce the risk Proper ventilation can reduce the risk

of rapid fire progressionof rapid fire progression Proper ventilation can increase Proper ventilation can increase

visibilityvisibility Proper ventilation can save firefighter Proper ventilation can save firefighter

liveslives

Final ReviewFinal Review Understand how to perform proper Understand how to perform proper

ventilation.ventilation. Venting for Fire makes fire attack saferVenting for Fire makes fire attack safer Venting for Life makes searching saferVenting for Life makes searching safer UT/AFD research has shown that PPV is UT/AFD research has shown that PPV is

effective in single family dwelling fireseffective in single family dwelling fires UT/AFD studies recommend using a UT/AFD studies recommend using a

coordinated PPV fire attack in single coordinated PPV fire attack in single family dwelling firesfamily dwelling fires

Coordinated PPV fire attack makes Coordinated PPV fire attack makes firefighters safer in single family dwelling firefighters safer in single family dwelling firesfires

Tactical PPV. This powerpoint was created using information provided to us by Chief Bob Nicks of the...

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Transcript of Tactical PPV. This powerpoint was created using information provided to us by Chief Bob Nicks of the...