Ventilation 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.

Ventilation Objectives Con’t Know the different tools used for ventilation. Know how to explain and perform vertical ventilation.

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

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

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

Ventilation Disadvantages or Improper Ventilation Fire spread Accelerated burning Puts firefighters in danger Triggers Backdraft Structural Integrity

Ventilation Dangers of ventilations Light weight construction. Can cause fire to intensify and spread. Places firefighters in danger. Backdrafts. Weather conditions.

Ventilation Complications Lack of Pre-planning Barred/Screen windows. Overhead obstructions. Access Weather Improper equipment Man power

Ventilation Complications (Con’t) Visibility Roof pitch/type

Ventilation Perform Initial Size- up Life Safety Conventional or Lightweight Construction Determine type and style of roof Location/Extension of fire Weather conditions Does the roof look safe (risk vs benefit)

Ventilation Conventional Construction Size of structural members = strength

Ventilation Light weight Construction Trusses Members are under compression and tension Size of individual members are small If one member fails, other members may fail

Ventilation Safety Considerations Minimum of two ladders for egress Approach from uninvolved Ladder strong areas of the roof Ladder extended 5 rungs above roof line Shut down saws before climbing Minimum of 2 firefighters

Ventilation Safety considerations Cont. Full PPE/SCBA Utilize Portable Radio Sound the roof!!!!!! Watch out for guy wires/electrical wires Coordinate cut with command Keep the wind at your back Work from weak to strong area of roof

Ventilation Safety considerations Cont. Always know your egress routs Perform ongoing size-up Only cut as deep as necessary Do not cut structural supports Cut away from your body Make the cut as close over the fire as possible

Ventilation Safety Considerations Cont. Advise command when ventilation is complete Exit roof ASAP

When Where How ?

Ventilation Ventilation Size-up Is there a need. (Why) Where is it needed. (Where) Type needed. (How) Structural conditions allow for safe operations. Timing (When)

Ventilation 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.

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

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

Ventilation Roof openings Cut large opening –Minimum 4’x4’ –Windward side Smaller openings –May be necessary do to conditions Trench cut –From Exterior wall to exterior wall –4’ wide

Ventilation Vertical Ventilation Uses: Attics Areas open to the roof

Ventilation

Roof Construction Lightweight wood or metal joist Heavy steel trusses Wood “I” beams Built-up roof Concrete Roofs Metal roofs

Ventilation 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

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

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

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

Ventilation 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

Ventilation 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

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

Ventilation Built-up roof construction OR PLYWOOD GRAVEL

Ventilation 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

Ventilation

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.

Ventilation 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.

Ventilation

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

Ventilation Arched Roofs Bowstring truss Trussless arched roof Lamella roof

Ventilation

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.

Ventilation Hand tools Axe Halligan bar Pike poles Sledge hammer Ladders

Ventilation Power tools Vent saws Chain saws Circle saws Reciprocating saws

Ventilation 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

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