FF1 Chapter 11 Tactical Ventilation
Kerf Cut
A single cut the width of the saw blade made in a roof to check for fire extension.
The two main considerations for positive pressure attack are ___ and_____
Fire location and exhaust to intake
What to assumption should firefighters make about any structure fire to guide their decisions when ventilating a structure
The structure itself consists of lightweight construction the fire in the structure is ventilation limited
Generator
used to provide power for electrically powered air movement device
True or false. A spongy roof can be an indication of a possible roof collapse but should not be taken as the only sign of roof instability
?
How was ventilation used to benefit extinguishment operations
Can create an interior environment or egress path with more tenable conditions
Four wind assisted ventilation windows and doors on the ___ of the structure should be open first to create an exhaust point
Downside
True or false it is safe to use stairwells or elevator shaft simultaneously for evacuation and exhaust path
False exhaust pass requires a separate path
Rapid fire development is caused when ____ from ventilation is introduced into the room causing heated gases to quickly reignite
Fresh air
Exhaust
In terms of ventilation The location where hot gases in the products of combustion leave a structure
Intake
In terms of ventilation, the location where air is being entrained toward a fire.
Exhaust opening
Intended and controlled exhaust locations that are created or improved at or near the fire to allow products of combustion to escape the building.
No mechanical devices are used door control would be an example
Natural horizontal ventilation
Stack Effect
Phenomenon of a strong air draft moving from ground level to the roof level of a building. Affected by building height, configuration, and temperature differences between inside and outside air.
Using a high-volume fan to create a slightly Higher pressure inside the structure than outside
Positive pressure ventilation
Louver cut
Rectangular exhaust opening cut in a roof, allowing a section of roof deck (still nailed to a center rafter) to be tilted, thus creating an opening similar to a louver.
Life safety
Refers to the joint consideration of the life and physical well-being of individuals, both civilians and firefighters.
Downwind side
Side of a building away from the wind blow pressure side
List for indicators of possible roof collapse
Spongy roof melting asphalt HVAC sagging/leaning fire coming from roof
Exposures
Structures or separate parts of the fire ground to which a fire could spread
Negative-pressure ventilation
Technique using smoke ejectors to develop artificial airflow and to pull smoke out of a structure
Why must firefighters consider exposures when ventilating
The routes the smoke and heated gases would naturally travel to exit that may be the same routes occupants need for evacuation and firefighters need for working
True or false Wind direction and strength is an important factor in tactical ventilation and should be reported to team members and or a supervisor
True
True or false an advantage of using mechanical ventilation to clear contaminated atmosphere is that it ensures more control of airflow
True
Vertical ventilation
Ventilating at a point above the fire through existing or created openings and channeling the contaminated atmosphere vertically within the structure and out the top. Done with openings in the roof, skylights, roof vents, or roof doors.
Hydraulic ventilation
Ventilation accomplished by using a spray stream to draw smoke from the compartment through an exterior opening
In order to prevent flashover of a compartment
Ventilation must be coordinated with fire attack
Windows as slow as ____ can affect the structure of making it wind driven
10 mph (15kph)
Mechanical ventilation
Any means other than natural ventilation. This type of ventilation may involve the use of blowers and smoke ejectors.
Which tool would be used to break windows and chop holes through roof decking when creating ventilation openings
Axe
Ventilating basement fires must be coordinated with fire attack but it's more important to determine what the first stage is _____ ventilating a basement
Before
Heating ventilating and air conditioning systems in windowless buildings unless specifically designed to clear the area of smoke are more likely to
Contain products of combustion
Is the primary mode of heat transfer from one compartment to another in a structure fire
Convection
Which action would be an effective way to keep the fire from growing and developing
Covering exterior doors and windows
Trench cuts are used to
Create a defensible line ahead of an advancing the fire
Trench cut
Cutting an exit opening in a roof of a burning building extending from one outside wall to the other to create an opening at which a spreading fire may be cut off
Positive pressure attack
Do you use an application of high-volume ventilation fans for the suppression that are intended to force heat and smoke towards desired exhaust openings
When performing natural horizontal ventilation doors on the ____ Side of the structure are opened to serve as intakes so that fresh air can enter in force smoke towards the exhaust opening
Downwind
When performing vertical ventilation it is important to
Ensure that the main structural supports are not cut when making an opening
When ventilating an environment_____ or ______ fire tech must be used immediately to cool the gases and surfaces in the room
Exterior or interior
True or false wanna flash over for us as long as firefighters are in full PPE they should be safe to continue working in these conditions
False PPE can fall under flashover condition
True or false ventilation equipment only needs to be inspected if a problem occurs
False routine inspection is necessary
True or false if winds are blowing at 10 mph (15 kph) or greater firefighters are safest when working with the wind blowing at their faces
False they would be safest with the winds at their back
What is a disadvantage or safety concern of performing hydraulic ventilation
Firefighters must be in a contaminated atmosphere to operate the nozzle
Ventilation without coordination will lead to
Flashover
Which of these is used to control the flow of fire gases and smoke during ventilation operations
Flexible duct
Your company response to a residential structure fire the incident commander determines that the fire is confined to the basement and then it will be necessary to ventilate the space the homeowner says that the basement is used only for storage and it's completely filled with boxes of them along the only exterior windows that provide access to the basement are small and covered with security bars the stairwell to the basement is accessible from the inside of the structure. What are two methods that may be used to ventilate the basement identify three hazards related to ventilation that the team may encounter what's stragedy maybe used to reduce the risk before ventilating the basement
Horizontal ventilation and breaching the floor floor collapse flashover Backdraft natural paths from the basement such as stairwells and hoist way shaft
Used to clear the room or structure smoke heat steam or gases after the fire is controlled using a spray stream from a fog nozzle
Hydraulic ventilation
Before ventilating it is important to cut a _____ to determine the President of the fire below and check the construction features of the roof
Inspection hole
What three incident priorities are achieved when tactical ventilation is implemented correctly
Life safety incident stabilization and property conservation
Used when the natural flow of air currents and currents created by the fire are insufficient to remove the smoke heat and fire gases
Mechanical horizontal ventilation
positive pressure ventilation
Method of ventilating a room or structure biomechanically blowing fresh air through an inlet opening in the space insufficient volume to create a slight positive pressure within thereby forcing containment in an atmosphere out the exit opening
Using air moving equipment to expel smoke from a structure by developing an artificial airflow or enhancing natural ventilation
Negative pressure ventilation
Tactical Ventilation
Planned, systematic, and coordinated removal of heated air, smoke, gases or other airborne contaminants from a structure, replacing them with cooler and/or fresher air to meet the incident priorities of life safety, incident stabilization, and property conservation.
You are assigned to the second do engine company on a single story residential structure incident commander has assigned your company to prepare for vertical ventilation explain what your size up will consist of what tools will you need for this assignment what factors should be considered before cutting a hole in the roof what factors should be considered before starting the positive pressure fan
Respond to fire establish a plan of action time of day life hazards areas building type of construction occupancy and weather conditions Power saw chainsaw ladders and a pike pole roof collapse stable structure spongy roof melting asphalt pressure intake and exhaust
Upwind side
Side of a building against which the wind is blowing, the high pressure side.
Ventilation
Systematic removal heated air smoke gases and other airborne contaminants from structure cool fresh air go to Staybridge and facilitate so funny revelations
Natural Ventilation
Techniques that use the wind, convection currents, and other natural phenomena to ventilate a structure without the use of fans, blowers, and smoke ejectors.
Horizontal Smoke Spread
Tendency of heat, smoke, and other products of combustion to rise until they encounter a horizontal obstruction. At this point they will spread laterally (ceiling jet) until they encounter vertical obstructions and begin to bank downward (hot gas layer development)
True or false firefighters should be positioned to keep doors closed as much as charged hose lines will allow in order to control the flow path
True
True or false tactical ventilation improves life safety for firefighters by creating tenable path of egress
True
True or false when firefighters control the flow of oxygen smoke and hot gases they then control the rate of the fire growth and spread
True
What should a fire fighter do before stepping off a ladder, parapet wow or other places of safety onto the roof of a burning building
Using a Halligan to make sure roof is safe and won't collapse
When considering breaching the floor the type of floor construction can be determined by
Using a pre-incident planning survey
Using a hole in the roof above the fire or opening existing roof access doors scuttles or skylights
Vertical ventilation
Positive pressure
When pressure is higher inside a structure than outside the structure, causing smoke and fuel gases to move toward lower-pressure openings.
Negative pressure
When pressure is lower inside a structure than outside the structure, causing fresh air from outside to move inside.