Ventilation Flashcards
Fires fought prior to 1970 were fueled primarily by ___materials
Legacy
Legacy materials consisted mostly of
Natural fibers and wood products, which produced a cooler fire with lighter colored less flammable smoke
Firefighters advancing a hoseline found a more defined ___, with cool air beneath a smoke layer, and a fire that took
Thermal layer, longer to fully develop (flashover)
Fires today are fueled predominantly by
Petrochemical based or synthetic products that produce a hotter, darker, blacked smoke
The change in basic building contents has made an environment that achieves flashover approximately __faster
30
Temperatures rise in buildings due to types of fuels and confined radiant heat, concentrations of poisonous fire gases build, and the building materials and contents confining the fire provide
Fuel for its growth
Because of todays fires develop more rapidly, firefighters often arrive on scene just prior to or during
Flashover
There is less defined smoke layer due to hotter, more advanced fire and an increase volume of combustible smoke, this creates
Low visibility and high heat environment
Vent prior to fire attack will introduce oxygen in an environment that is fuel rich and allowing fire
To grow rapidly
___ is responsible for determining strategy and tactics on each working incident
IC or command
When considering ventilation, command should consider vent for __ and then for fire co trip and property conservation
Life safety
Systematic and coordinated removal of the products of combustion from a structure involved in a fire
Ventilation.
The movement of heat and smoke from higher air pressure within the building fire area to all other lows air pressure areas both inside and outside of a structure involved in a fire
Flow path
The rate at which energy (heat) is released by the burning of a fuel and oxygen mixture
HRR heat release rate
The opening of a window or door in a structure opposite the advancing interior crews for the purpose of allowing heat, smoke and fire gases to escape from the structure into the atmosphere
Coordinated horizontal vent
A method of ventilating a structure
by mechanically blowing fresh air into the space in sufficient volume to create a
slight positive pressure within, thereby forcing contaminated air out an exhaust
opening.
Coordinated positive pressure ventilation
Opening the roof or existing roof openings for
the purpose of allowing the products of combustions (smoke and heated gases)
to escape into the atmosphere.
Coordinated vertical ventilation
The practice of closing doors while conducting a search or during forcible entry prior to initiating firefighting operations. “Controlling the Door”
will isolate the fire area limiting spread to uninvolved areas and eliminating flow
paths that are not part of the ventilation plan.
door control
Radio terminology used to let the ventilation team know it is an appropriate time to break the selected window, or for the ventilation team to inform interior crews that they are preparing to break a window. Example: “Truck 2 from Engine 30, we are knocking down the fire. You can take glass on the Bravo/Charlie corner.” “Truck 2 copy, taking glass.”
Take glass
The direction that is upwind from the intended ventilation point (door, window, or the selected location for a roof ventilation hole).
windward side
The direction that is downwind from the intended ventilation point (door, window, or the selected location for a roof ventilation hole).
Leeward side
The primary responsibilities of the first due truck company on a box alarm will
be
Life Safety
The primary responsibilities of the second due truck company on a box alarm will be \____
assisting with unfinished first due truck company responsibilities, laddering upper floors for egress, and vertical ventilation if needed
Once it is
determined that no rescue problem exists, the need for a second truck will be evaluated by Command. The second truck will be returned in service as ___
soon as practical.
Truck company functional assignments will be made by the ____each morning at roll call
company officer
Irons Firefighter - Entry set, pick head axe, other forcible entry tool needed specific to the incident, search rope if needed.(inside team)
Irons Firefighter .
6 foot hook, TIC (if available), and pick head axe. Consider the need for a water extinguisher. (inside team)
Hook FF
(outside team) TIC (if available), pick head axe, appropriate sized ladder to reach upper floor windows for ventilation and egress of civilians and
firefighters.
AO
Outside 6 foot roof hook, pick head axe, and a second ladder to reach upper floor windows for ventilation and egress of civilians and
firefighters.
OV FF
These are recommended assignments, but actual assignments each day are at the ____, based on crew familiarity and experience levels.
Officer’s discretion
Typically tower ladders, aerial platforms, and straight ladder trucks will assign
the two inside Firefighters as the ___ making one the Hook Firefighter
and the other the Irons Firefighter.
inside team
. Much like the overall fire ground strategy, ventilation strategy can be ____
offensive, defensive, or a combination of the two
It is common for a ventilation opening in a fire building (window, doors, roof openings) to act simultaneously as ___
an inlet for fresh air and an exhaust vent for the products of combustion.
Based on varying building configurations and ventilation profiles, there may be ___ flow paths during a structure fire.
several
Any open window represents a ____ vent point that will become a flow path if not isolated from the fire area.
low-pressure
By practicing ___ firefighters can isolate the fire area and shut off potential flow
paths
door control
__- is a measure of the size of the fire compared to the thermal hazard or
effects of the fire.
HRR
Providing oxygen to a ventilation limited fire will increase the ___
HRR
Increases is the ___ will result in increased heat and smoke production in the fire area and in all flow paths
HRR
If possible, openings should be made ____the operating hose line, which will provide a flow path for steam, heat and smoke to exit the
structure ahead of the nozzle team.
opposite
Ventilation openings should ___ be created behind an advancing hose line.
never
The keys to any type of successful ventilation opening are proper ___ and
proper ___ with the interior attack line(s).
Placement and timing
Utilizing mechanical blowers to exhaust smoke, heat, and the products of combustion out an opening while entraining cool, clean air into the compartment.
Negative pressure
The use of high-volume fans to create a slightly
higher pressure within a structure at an inlet opening, thereby
exhausting heat, smoke, and products of combustion out an
exhaust opening.
Positive pressure
Utilizing the air movement created by a fog or broken
stream to help draw the products of combustion out of the
structure. This method is typically used after the fire has been
controlled and when other types of ventilation are unavailable.
Hydraulic
When working on lightweight construction buildings firefighters ____ conduct roof operations directly over the fire
must not
____ break windows if the location of the fire is
unknown
DO NOT
