1. Ventilation

2. Goal
Given information on ventilation the firefighter will be able to identify when and where to safely apply ventilation so that heat, smoke, and gases can be removed from a structure to improve conditions for fireground operations. This will be done to a written test accuracy of 75% and complete the practical evolutions in the allotted time to the instructor’s satisfaction.

3. Objectives The student will:
Understand the importance of ventilation.
Be able to identify when and where to ventilate.
Understand the dangers of ventilation.
Be able to identify the different types of roof construction.

4. Objectives Con’t Know the the different tools used for ventilation.
Understand the compilations of ventilation
Have an understanding of positive and negative pressure ventilation.
Know how to explain and perform vertical ventilation.

5. Objectives Con’t Know how to explain and perform natural ventilation.
Know how to explain and perform horizontal ventilation.

6. Overview Importance of ventilation Different techniques
Advantages and disadvantages
Precautions and dangers
Roof Types, and their construction
Different types of ventilation
Tools needed for ventilation

7. Ventilation
The systematic removal and replacement of heated air, smoke, and gases from a structure with cooler air

8. Advantages Rescue Increases survivability of trapped victims
Improves visibility, and reduces heat levels
Reduction of flashover and backdraft potential
Fire attack
Fire spread control
Property Conservation
Rescue
Replaces heat, smoke and gases with cooler, fresher air
Improves visibility to locate and remove victims
Fire
Location of fire
Lowers danger of firefighters injuries and burns
Visibility
Removal of smoke and replacement of fresh air
Property conservation
Allows quicker extinguishment reducing future damage
Backdraft and flashover potential
Removal of super heated air and gases
Know the signs, and ventilate properly
Fire spread
Reduces mushrooming , relieving the heated gases and smoke
Increasing survivability for victims
Replaces heat, smoke and gases with cooler, fresher air
Survivable atmosphere until rescued

9. Disadvantages or Improper Ventilation
Fire spread
Accelerated burning
Puts firefighters in danger
Triggers Backdraft
Structural Integrity
Lack of communication
Wrong location
To soon
Venting behind firefighters
Weaken structure integrity
Cutting through floor joist, rafters, studs, etc.

10. Dangers of ventilations
Light weight construction.
Can cause fire to intensify and spread.
Places firefighters in danger.
Backdrafts.
Weather conditions.
Weakens and fails quickly
Provides fuel
Open areas for fire spread
Working on weakened roofs or floors.
Venting incorrectly
Wind, rain, snow, ice, electrical storms. (FROST)

11. Complications Lack of Pre-planning Barred/Screen windows.
Overhead obstructions.
Access
Weather
Improper equipment
Man power
Preplans – Roof construction such as Parapet wall, Mechanical equipment, Concrete Pre-cast, Pre-stressed, poured reinforced or light weight, metal decking, double roofs
Overhead – Wires, trees, Other bldgs.
Weather – Lighting, Wind, Rain, Snow, Ice, etc.
Equipment – Saw blades, Not ready for the job (Out of gas), Dull/dirty ax blade.
Man power – Air supply to do the job
Power and other wires overhead.
Antennas

12. Complications (Con’t)
Visibility
Roof pitch/type
Visibility – Heavy Smoke
Construction – Parapet wall, open hatches, stairways
Step pitched roofs or less can be walked
Slate, tile shingles built-up, metal, etc.

13. ? Ventilation Where When How
Cooler air improve firefightering operations, life safety for rescue, conditions for trapped occupants. And reduces conditions that support Flashover and Backdraft.
In newer home ventilation has to be performed quicker.(Energy Efficient)
Plastics
How

14. Ventilation Size-up Is there a need. (Why) Where is it needed. (Where)
Type needed. (How)
Structural conditions allow for safe operations.
Timing (When)
NEED
What are the conditions in the structure. (Heat,fire,smoke etc.)
Life hazards. (Type of structure, Commercial, Assembly, Medical, Dormitory - Hood, MSD.)
Structural stability
Are you actually causing unnecessary damage. (Pre-existing openings)
WHERE
Location of fire.
Wind direction
Location of victims and escape routes.
Bldg. construction (Concrete, Wood, Roof type, High rise)
Structural integrity, Wreaking roof
Location of pre-existing openings. (Sky lights, HVAC, Exhaust fans, Windows and doors)
Exposures, Contents (Are you endangering other bldgs or it’s contents)
Fire spread
Preplanning
TYPE
Horizontal
Vertical
Natural
Mechanical

15. Coordinated Fire Attack
Vent as close to the point of origin as possible coordinating with interior attack crew.
Hose line ready and charged while firefighters are advancing.
Ventilation of the fire room with outside vent person.
Most direct route
Decrease property loss
Easier for attack
Lessens the physical demand on you.
Fire can intensify
Cause more structural and property damage
Ventilation can be done from inside if needed

16. To keep smoke, heat, and gases away from victim.
Primary Consideration
RESCUE OR
SUPPRESSION
PRIORITY
WITH INTERIOR ATTACK
To keep smoke, heat, and gases away from victim.
To reduce heat and
Increase visibility
For firefighters

17. Types of Ventilation
Natural
Horizontal
Vertical
Mechanical

18. Natural Ventilation – The means of ventilating a structure without the assistance of powered equipment.

19. Natural Ventilation
Wind.
Currents created by the fire.
Use Caution!!!

20. Horizontal Ventilation – Is the venting of heat, smoke and gases through wall openings such as windows and doors.

22. Horizontal Ventilation
Uses:
Residential
Multistoried structures
Large unsupported open spaces.
Residential – Fire/smoke not involving the attic.
Multistoried Structure – Fire not involving top floor or attic.
Unsupported open spaces that have been damaged by fire weakening the roof structure.

23. Vertical Ventilation
Opening the roof or using existing roof opening to allow heated gases and smoke to escape.

24. Natural Opening Sky lights Scuttle Hatches Windows Doors Shafts
Ventilators
Stairways
Use natural openings before cutting if possible
May be used to supplement an opening you have to cut

25. Roof openings Cut large opening Smaller openings Trench cut
Minimum 4’x4’
Windward side
Smaller openings
May be necessary do to conditions
Trench cut
From Exterior wall to exterior wall
4’ wide
One large is more effective than several small ones.
Small openings may have to be used do to conditions of structure

26. Vertical Ventilation Uses: Attics Areas open to the roof
Cathedral ceiling, Churches, auditorium, A-frame, etc.
Punch out ceilings to make open to roof

28. Mechanical Ventilation (Forced) – The means of ventilating a structure with the assistance of powered equipment. Positive-pressure ventilation (PPV), and Negative-pressure ventilation (NPV)

30. Positive-pressure ventilation (PPV)
Induces fresh air into a confined area or structure resulting in an increase of pressure in that area which forces contaminated air through pre-selected and/or controlled openings
Must coordinate with operation, and attack crews
Can cause fire spread, and intensity
Can trap firefighters, and or victims

31. PPV Advantages Two times more effective than NPV
Does not block doorways
Does not expose personnel to contaminants while positioning blower
Provides fresh air, reduces heat, and CARBON MONOXIDE during overhaul operations
Must keep personnel out of the path of air movement
Must assure of proper exhaust openings.

32. Disadvantages Noisy Not effective if there are to many openings
Can cause fire spread, or ignite smoldering embers
Raise CO levels with gas fans.
Very loud at fan location
Not effective if there are to many openings
Causes fire spread if:
Timing is off
Location is wrong
Building construction- voids spaces, balloon frame etc.
Gas fans can raise CO levels. However by regulating exhaust opening that can be lowered.

33. PPV Fan Placement
A single fan should be placed so the cone of pressurized air JUST covers the opening
Tilting the fan back about degrees will enhance the operation
Square box type fans can be stacked to achieve the same effect.( one fan on top of the other)

34. Back far enough to seal the opening
Single unit operation
Exhaust opening should b ¾’s to twice the size of entrance
EXHAUST
PATH
Back far enough to seal the opening

35. YES!
If you don’t have standard PPV blowers on your apparatus, simply use NPV devices
and stack them on top of each other, then reverse their positioning placing exhaust side in.
- SMOKE EJECTORS -

36. PPV Fan Placement
Two fans one in front of the other (series, tandem, or in line)
Front fan (Largest) about 2 feet from opening, and the back fan will be set back far enough to cover the opening with pressurized air
Two or more fans side by side(parallel or dual)
Fans should sit side by side and back far enough to cover the opening with pressurized air

37. Series, tandem, or in-line
EXHAUST
Positive Pressure
DISTANCE
2-3 feet Larger Fan
Back far enough to seal the opening

38. Parallel or dual

39. Exhaust opening
Most effective when the exhaust opening is three quarters to two times the size of the entrance opening.
Varies do to size of the fan or the amount of fans operating.
Optimum efficiency is easily obtained by a combination of training and practical experience.

40. Determine PPV fan Size for a Given Structure
Apply the PPV Rule of Thumb
- Single family dwelling with up to 2,000 square feet: 18- to 21-inch fans
- Ranchers and multistory dwellings up to 4,000 square feet: 24-inch fan
- Larger structures (greater than 4,000 square feet) require multiple fan application with 2 to 3 24-inch fans
- Always use multiple fans on high-rise structures 10 floors or greater

41. Negative-pressure ventilation
Draws contaminates from interior to the exterior causing a negative-pressure in the contaminated area allowing fresh air to enter from an outside source through another opening.

42. Advantages Usually operates off of a 110 volt
Usually explosion-proof motor
Easily adapted to house outlets
Can be used in an explosive atmosphere

43. Disadvantages Exposes personnel to the contaminated area
Placement in doorways and windows require hangers, straps or other accessories to position them effectively
Block entrances and hallways
Contaminates are drawn through the fan causing additional cleanup and maintenance
Exposes personnel to the contaminated area
Placement in doorways and windows require hangers, straps or other accessories to position them effectively
Block entrances and hallways
Contaminates are drawn through the fan causing additional cleanup and maintenance
Added noise levels in area of operations.

44. Mechanical Devices Gas Fan Electric Fan Mobile units HVAC systems
Exhaust Systems
Hose steams (Hydraulic)
Gas Fan
Electric Fan
Mobile units
HVAC systems
Exhaust Systems
Hose steams (Hydraulic)

45. Gas Fans 2-cycle and 4-cycle engines 18 to 24 inch in diameter
3200 to 15,000 CFM
Many different manufactures and styles
Maintenance ( Gas, oil, and air filters )
Can cause CO levels to rise in structure
2-cycle and 4-cycle engines
18 to 24 inch in diameter
3200 to 15,000 CFM
Many different manufactures and styles
Maintenance ( Gas, oil, and air filters )
Can cause CO levels to rise in structure

46. Electric Fans Both PPV and NPV Require electric cords
NPV fans sizes 16 to 24 inch, from 2 to 3 hp
Square or circular encased, including motor
PPV fans are 18 to 24 inch, from 3200 to 30,000 CFM
Both PPV and NPV
Require electric cords
NPV fans sizes 16 to 24 inch, from 2 to 3 hp
Square or circular encased, including motor
PPV fans are 18 to 24 inch, from 3200 to 30,000 CFM

47. Mobile ventilation units
Diesel
PTO
Hydraulic
30,000 to 211,000 CFM
Diesel
PTO
Hydraulic
30,000 to 211,000 CFM

48. HVAC Systems
Some are designed to reverse to draw out contaminated air from buildings
Maintenance personnel from building will provide that information
If unsure Turn units off.
Preplanning
Some are designed to reverse to draw out contaminated air from buildings
Maintenance personnel from building will provide that information
If unsure Turn units off.
Can move contaminants to other parts of building
Check units for fire extension
Preplanning

49. Exhaust Systems Some buildings have systems in place for other uses.
Maintenance personnel from building will provide that information
Preplanning
Some buildings have systems in place for other uses.
Maintenance personnel from building will provide that information
Preplanning

50. Hose Stream (Hydraulic)
Usually used in area of fire after knockdown to remove heat, smoke, and gases
Using fog pattern at 85 to 90 degrees at least two from opening.
Advantages:
- Removal of contaminants prior to other mean of ventilation are started
Disadvantages:
- Drawing contaminants over firefighter
- Depleting water supply
- Interfere with outside operations
- Cause icing conditions during cold weather

51. Care and Maintenance PPV Blowers or Fans
- Use proper oil and fuel mixtures
- Keep belts tight and snug
- Keep shroud(s) intact
- Check fluid levels. Change fuel regularly and replace with fresh
- Run blower
- Keep rubber feet or base intact
NPV Blowers or Fans
- Clean blades and motor regularly
- Keep electric cords and switches intact
- Listen for any unusual noises during operation
PPV Blowers or Fans
- Use proper oil and fuel mixtures
- Keep belts tight and snug
- Keep shroud(s) intact
- Check fluid levels. Change fuel regularly and replace with fresh
- Run blower
- Keep rubber feet or base intact
NPV Blowers or Fans
- Clean blades and motor regularly
- Keep electric cords and switches intact
- Listen for any unusual noises during operation

52. Contra indicators for PPV
No properly trained crew
When interior search or rescue teams or occupants are between the fire and exit point of smoke
For well-involved attic fires with no egress venting
When fire is present in the walls of balloon construction and no egress point is identified
When backdraft conditions are evident.
When the origin of fire is unknown.
Too many openings in a structure preventing air flow from effectively pressurizing interior
No properly trained crew
When interior search or rescue teams or occupants are between the fire and exit point of smoke
For well-involved attic fires with no egress venting
When fire is present in the walls of balloon construction and no egress point is identified
When backdraft conditions are evident.
When the origin of fire is unknown.
Too many openings in a structure preventing air flow from effectively pressurizing interior

53. Ventilating multiple floors
Pressurize stair shaft common to all floors
Start with lower levels and work up
Vent horizontally through exterior openings
Vent to opposite stair shaft
Pressurize stair shaft common to all floors
Keeps path of egress clear for firefighters
Keeps contaminants from spreading
Start with lower levels and work up
Vent horizontally through exterior openings
Doors
Windows
Vent to opposite stair shaft
Then vertically out

54. Flat
Mansard
Shed
Butterfly
Hip
Gable
Lantern
Gambrel
Arch
Sawtooth

55. Lightweight wood or metal joist Heavy steel trusses Wood “I” beams
Roof Construction
Lightweight wood or metal joist
Heavy steel trusses
Wood “I” beams
Built-up roof
Concrete Roofs
Metal roofs
Built-up Roof
Used on residential or commercial buildings
- Residential is usually apartment buildings
Solid wood rafters / lightweight wood or metal trusses
Plywood sheathing / metal decking
Tar, insulation, layers of composition and tar, gravel

56. Lightweight wood or metal trusses
Trusses in place of rafters
Wood or metal decking
Built-up roof
Allows horizontal fire spread
Fails after 5-10 minutes of fire exposure
Trusses in place of rafters
Wood or metal decking
Built-up roof
Allows horizontal fire spread
Fails after 5-10 minutes of fire exposure

57. Heavy steel trusses Metal decking with built-up roof
Starts to fail at 1000 degrees
Metal decking with built-up roof
Starts to fail at 1000 degrees

58. Wood “I” beams Substitute for lightweight trusses
Contributes fuel to the fire
Fails within 5 to 10 minutes of fire exposure
Substitute for lightweight trusses
Contributes fuel to the fire
Fails within 5 to 10 minutes of fire exposure

59. Concrete roofs Precast concrete Lightweight concrete
Reinforced concrete
To vent this type is difficult and time consuming
Use natural openings, skylights, scuttles, ventilators, stairwells
Precast concrete
Lightweight concrete
Reinforced concrete
To vent this type is difficult and time consuming
Use natural openings, skylights, scuttles, ventilators, stairwells

60. Metal roofs Light-gauge steel Corrugated galvanized sheet metal
Aluminum
Vent with power saws using metal cutting blades, axe, or sheet metal cutters.
Use natural openings
Light-gauge steel
Corrugated galvanized sheet metal
Aluminum
Vent with power saws using metal cutting blades, axe, or sheet metal cutters.
Use natural openings

61. Flat Roof Industrial, commercial, and apartment buildings
Frequently pierced by chimneys, vent pipes, shafts, scuttles, and skylights
May be surrounded and or divided by parapets
May have HVAC unit on them
Industrial, commercial, and apartment buildings
Frequently pierced by chimneys, vent pipes, shafts, scuttles, and skylights
May be surrounded and or divided by parapets
May have HVAC unit on them

62. Flat roof construction
Wooden, metal, or concrete joist
Wooden or metal decking
Waterproof materials, insulation, gravel
Reinforced, lightweight concrete, or precast concrete
Wooden, metal, or concrete joist
Wooden or metal decking
Waterproof materials, insulation, gravel
Reinforced, lightweight concrete, or Precast concrete

63. Built-up roof construction
GRAVEL
Built-up Roof
Used on residential or commercial buildings
Solid wood rafters / lightweight wood or metal trusses
Plywood sheathing / metal decking
Tar, insulation, layers of composition and tar, gravel
OR PLYWOOD

64. Built-up Roof Opening built-up roof Remove gravel if present
Make inspection cut
Cut insulation and composition down to decking
Remove materials, sound roof for rafters or bar joist, then cut decking and remove.
Be careful not to cut to deep to avoid causing structural damage to the rafters
Removal of gravel only needed at starting points
Inspection cuts are to verify fire location and feasibility of ventilation
- Is construction wooden joist or lightweight construction
- Lightweight construction fails quickly under fire conditions
- How to open roof (wooden or metal)
Always work toward your except route.

66. Opening a flat roof Determining the location of the opening
Location and extent of fire
Wind direction
Exposures
Obstructions
Open using the built-up roof method.
Determining the location of the opening
Location and extent of fire
Wind direction
Exposures
Obstructions
Open using the built-up roof method.

67. Pitched Roofs Rafters or trusses 1X boards or plywood sheeting
Felt paper
Shingles- wood, asbestos, composition, metal, slate or terracotta tile.
May be gypsum slabs, approximately 2” thick, laid between metal trusses.
Rafters or trusses
1X boards or plywood sheeting
Felt paper
Shingles- wood, asbestos, composition, metal, slate or terracotta tile.
May be gypsum slabs, approximately 2” thick, laid between metal trusses.

69. Opening a pitched roof
Determine the location of the opening same as flat roof
Place roof ladder on the windward side of opening
Locate the rafters
Cut opening working the farthest distance from you towards yourself
Remove the decking
Push a tool into the hole to open a possible ceiling below
Determine the location of the opening same as flat roof
Place roof ladder on the windward side of opening
Locate the rafters
Cut opening working the farthest distance from you towards yourself
Remove the decking
Push a tool into the hole to open a possible ceiling below

70. Arched Roofs Bowstring truss Trussless arched roof Lamella roof

72. Opening an arched roof Cutting is the same as a pitched roof
Use of a roof ladder would be unlikely
Because of the potential for sudden collapse under fire conditions, roof operation should be done from an aerial ladder or tower.

73. Hand tools Axe Halligan bar Pike poles Sledge hammer Can opener
Hand saws
Ladders
Axe, TNT tool
Halligan bar
Pike poles, halligan hooks, etc.
Sledge hammer
Can opener
Hand saws
Ladders

74. Power tools Vent saws Chain saws Circle saws Reciprocating saws
Many makes and models
Gas or electric
Chain saws
Circle saws
Wood, metal, and concrete blades
Reciprocating saws
Wood or metal blades

75. Power tool safety Proper maintenance
Know tool operations and capabilities
PPE
Start tool before taking to operational area
Never carry, hoist, or climb while running
Keep front arm stiff while operating tools
Work with a partner
Proper maintenance
Chains or blades tight and sharp
Brakes devices working properly
Proper fuel, and oil levels
Know tool operations and capabilities
How to start
How to change blades or chains
Different type blades, and their uses
PPE
Start tool before taking to operational area
Never carry, hoist, or climb while running
Keep front arm stiff while operating tools
Prevents injury from kick-back
Work with partner
Watch your back
Stabilization

76. Review Discussed the importance of ventilation
Discussed ventilation techniques
Discussed the advantages and disadvantages of ventilation
Discussed precautions and dangers of ventilation
Discussed the different types of roofs, and their construction
Discussed different types of ventilation
Discussed the tools needed for ventilation