St Chpt 8 Flashcards
An _______ Is the preferred strategy whenever conditions and resources permit an interior attack
Offensive fire attack
A____________Limits operations to the exterior, generally resulting in a large property loss and limiting rescue options
Defensive decision
The _________ Is based on staffing available to conduct an interior attack, water supply, ventilation, and most importantly a risk versus benefit analysis.
Offensive versus defensive decision
The objective of an _________ Is to apply enough water directly to the burning fuel to achieve extinguishment, thus providing a safer work Environment for firefighters, facilitating rescues, and reducing property damage.
Offensive fire attack
Are the most effective way to save lives and property, but are potentially the most dangerous strategy
Offensive operations
The _____ Is critical and the basis of the entire incident action plan
Offensive/defensive decision
Calculating the _______ Allows the incident commander to match the number And size of firelines to flow requirements
Calculating rate of flow
William Clark uses a derivation of the fire compartment volume in cubic feet divided by ________ to determine rate of flow in gallons per minute.
V/100
John Coleman notes that a hose streams extinguishing capability will generally be determined in about ______
30 seconds
He further recommends a trial and error approach in stating, “If you are at the top of a stairway and have a line directing water at a well involved second floor attic and you don’t darken down the fire within _______ or so, get more water
30 seconds
The continued use of initial attack lines when they are clearly overpowered by the fire is a sign of _____.
Poor training and the lack of fire ground discipline
Many refer to this failure to recognize the need for larger fire streams as a ________.
Residential mentality
One method of avoiding the problem of always using the same Fireline is to write _____ Requiring the use of 2 1/2 inch what happens when confronted with the fire in a large commercial building
SOPs Standard operating procedures
The success rate of the trial and error method is highly dependent on the ______ or the standard preconnected hose line
Flow rate
The ______ is probably the most commonly used method of determining flow rate.
Trial and error method
Royer Nelson formula
V/100
National fire academy formula
A/3
Is based on the very efficient cooling effect of water being converted to steam
Lloyd layman’s indirect attack theory
Recent research conducted by underwriters laboratories indicates that “________” by applying water into the fire compartment as quickly as possible, from the exterior can make conditions in the entire structure better.
Softening the target
In the absence of visible fire or heavy and/or pushing smoke conditions, the soften the target tactic _______.
Does not apply
The correct way to _______ is to apply a straight spraying or smoothbore stream at a steep angle through the window and off of the ceiling to allow water to rain down onto the burning contents and cool the hot gases.
Soften the target
Is widely used to reduce fire growth and prevent flash over by directing short blasts of water toward the ceiling
Pulsing
The _______ is based on the premise that the best rate of application is one that results in control of the fire within 30 seconds of effective application 80% efficiency
Royer Nelson formula
The major sumptuous of Royer and Nelson that structure fires are primarily__________ is true for many fires.
Oxygen controlled
Require less water than a free burning fire. Therefore, the royer nelson formula may understate the need in a well ventilated large area fire
Oxygen ventilation controlled fires
Although Clark advocates the v/100 formula, he knowledges that the progression to flashover is primarily based on the________ .
Ratio of the surface area of the fuel to the size of the enclosure
The progression to flashover begins with the fuel being heated until vapors being generated ______ ignite
Pyrolysis
The national academy developed the _____ formula for use in their fire courses.
A/3
An article by royer Nelson recognizes that the V/100 rate of flow formula is primarily a ____.
Planning tool
Large volume fires are the fires that require the application of a ______.
Rate of flow formula
Both the royer Nelson and national fire academy formulas ignore the _________; this is a substantial weakness in these formulas.
Fuel load and fuel type
If two 1 3/4 lines are not controlling a fire with a calculated rate of flow of 100 gpm the problem is probably a failure to _______
Effectively apply water
When confronted with a fire exceeding the rate of flow for two standard pre-connected hose lines with no pre-incident planned rate of flow data available, the IC will be forced to estimate the size of the involve compartment to determine the rate of flow requirement or else revert to_______.
Trial and error methods
The _______Formula is based on fuel consumption being oxygen controlled by the volume of the enclosure and does not reduce the rate of flow by the percentage of volume of the enclosure involved in the fire
Royer nelson formula v100
The ______ Is based on the area of involvement rather than the volume of the enclosure; therefore, a reduction by the area of involvement is recommended
National fire Academy rate of flow
The national fire Academy recommend a percentage of involvement modifier in applying the _____ rate of flow.
A3
Most fires Can be controlled with less then ___ during the ignition phase
1 gpm
Are the most accurate as they are based on actual fire experience and consider the important factors of area of involvement and fuel load
Sprinkler rate of flow calculations
Are not suitable for onscene use unless the pre-incident plan identifies flow requirements
Sprinkler rate of flow calculations
Are more effective in getting the wet stuff directly on the red stuff and they pre wet the exposed fuel much as fire fighters with hose lines wet exposures
Sprinklers
A close the royer Nelson and national fire academy rate of flow calculations systems show that the _______yields a higher rate of flow in most situations
National fire Academy system
When confronted with a fire in an area that is beyond the control to standard preconnected hose lines and in which the fire flow has not been preplanned ________ may be easier to apply
A3
Whether rate of flow is calculated in advance or on the fire ground, the IC should modify the formula on the basis of _____
Trial and error
When the average hose lay exceeds 250 ft, it would be wise to use a _____ or larger preconnected lines to compensate for the additional friction loss.
2in
Pressure loss due to elevation is ______ per foot of elevation
0.434
Many fire departments use a rule of thumb calculation for elevation loss, such as _____ per floor.
5 psi
Calculating friction loss is a bit more challenging than elevation, because friction loss in hose varies by size, hose type, manufacturer, age, and condition. It is best to use _________ to determine the actual friction loss in the hose carried on department apparatus.
Calibrated pressure gauges
One of the advantages of a pre-connected hose line is establishing a _________, Which eliminates the need to calculate hydraulics at the incident scene
Standard pump discharge pressure
Probably the most important point to be made is that departments should _______ their nozzles On a regular basis to ensure they are operating properly and to confirm the flow that can be expected from the hose nozzle configurations available on their apparatus
flow test
Every department should perform flow tests On their hose and nozzle combinations using a
Calibrated flow meter
A handheld line can generate a flow of up to
350 gpm
NFPA 14 standard for the installation of standpipe and hose systems, requires that a sign be posted, usually at the main control valve, stating the location of the two most _______ hose connections
Hydraulically remote
Standpipe outlets with a residual pressure exceeding 100 psi or a static pressure exceeding 175 psi are required to be equipped with ________.
Pressure reducing valves
When selecting a nozzle/hose combination for standpipe operations, consider the pressure at the standpipe discharges and select standpipe hose and nozzles based on the _______
Lowest pressure
One major disadvantage in using the aerial device for hose lines is that it is ___________.
No longer available for removing occupants or firefighters from the building
From an empirical point of view, the solid core of water produced by the ______ would appear to deliver more water with better penetrating power than a straight stream or large droplet stream.
Solid stream nozzle
Generally speaking, an _______ involves applying water from an interior position or an exterior position in close proximity
Offensive attack
In conducting an _____, the idea is to keep ventilation to a minimum while introducing a wide angle fog stream directed at the ceiling through the smallest possible opening, such as partially closed door or window
Indirect attack
Occasionally, a flat roof is covered by a peaked roof making it especially difficult to access the space between roofs.
Limiting openings to a small hole made to insert a piercing or larger nozzle may be the solution to this difficult fire
The ______ is preferred in the vast majority-of situations where conditions permit an offensive attack.
Direct attack
Class A fuels must be vaporized by heating the solid materials until combustible vapors are emitted; this process is known as
Pyrolysis
When firefighters encounter very high heat conditions, indicative of an impending flashover, directing stream overhead _______ is advised, but this should be done using short intermittent blasts with a straight stream aimed at the ceiling in a pulsing fashion before actually entering the fire compartment
Pulsing
Another way to soften the target is to apply water to the fire from an exterior opening. This approach is sometimes referred to as a _________.
Transitional attack
The ______ involves directing a stream from the exterior into a room that is involved in fire where the fire has self vented
Transitional attack
Fire can also extend vertically up the exterior of the building from windows or other openings on the fire floor. All of these potential routes of fire extension within the building are classified as ____ and need to be checked and protected with a hose line as required.
Internal exposures
Fire can extend to adjacent buildings _____as well.
External exposures
For most situations, the maximum outlet pressure to a flowing hose line will be _____.
100 psi
Mathematically the rates of flow would be equal for a ____ ceiling
33 1/3
The threat to human life is always the _______
First consideration
Only in situations in which flows excess of 1000 gpm are anticipated from a single pumper or for extremely long relay lines (over 700 ft) is it necessary to place another ______ in a large diameter hose water supply layout
Pumper
Venting is normally considered an offensive tactic however, the _____ is sometimes referred to as a defensive cut
Trench cut
Can be used in any large structure and are particularly suited to U shaped apartment buildings and garden apartments
Trench cuts
The 2000 ft two story single family dwelling with no basement and no exposures is sometimes referred to as a “______”
Low hazard occupancy
A _____ has the staffing necessary to function as a unit, such as an engine company, a truck company, or medic unit.
Staged apparatus
Apparatus without adequate staffing are classified as _______ rather than staged
Out of service or parked
Proponents of ________ claim that the product is superior to untreated water when used as a suppression agent or to protect exposures from radiant heat.
Class A foam
The second expected advantage of class A foam is that there is less water damage because _______.
Less water is used
Finally, prewetting fuels and providing a foam layer on an exposure seem to be the most useful applications of ______ in an urban or suburban setting.
Class A
Given the difficulty in calculating rate of flow at the fire scene, a strong recommendation is made to include the rate of flow as part of the preincident plan information when the flow exceeds the capabilities of the _______ used by the department
Two standard initial attack hose lines
Are based on the area or volume of the compartment on fire
Rate of calculations
By taking the concept of matching the hose line to the rate of flow one step further, it is possible to determine in advance the number and size of hose lines needed to combat fires in dwellings, apartment buildings, and small businesses. This is a form of preincident planning that is, preincident planning by
General occupancy
A 1 3/4 in. hose line is acceptable only when using the
V/100 formula royer Nelson
Given that the national fire academy figures tend to overstate the case, and there should always be a back up line, it can be concluded with a fair degree of confidence that fires within one and two family dwellings are normally within the flow capabilities of a ______ with back up line
1 3/4 in or 2 in.
Properties that are already equipped with a sprinkler system should have a ________ with all of the required water flow requirements stamped into the plate
Plate on the riser
Royer and Nelson assume an _____ efficiency in getting water into the immediate fire area
80%
Assuming that the first arriving company will place a 1 3/4 in. or larger attack line in position, the _______ method is generally applied
Trial and error method
When more than two 1 3/4 in hose lines are needed to control the main body of fire, there is an obvious need for_____ hoselines if an offensive attack is to continue
2 1/2 in
Applying water to the fire for 15 seconds in a small residential fire prior to making entry or just an entry is made ______, reducing heat
Softens the target
Just as with softening the target attack, the fire stream is applied for a short time to knock down a heavy volume of fire, making entry possible. The fire stream should be a handheld _______, not a fog stream or master stream
Solid or straight stream
There are times when the fire is shielded by non burning materials, such as in a warehouse with rows of high stacked commodities. If possible, the hose should be moved to a position that allows a direct attack. If this is not possible, then _______
Deflecting a solid or straight stream off of the ceiling and allowing the droplets to fall on the fuel is an alternative
Protecting exposures can involve hose lines on the exterior or interior of the exposed building. When working on the exterior, _____ are often the streams of choice.
Master streams
In an area with hydrants, providing at least _____ for a working structure fire is considered good practice
Two water supplies
Where the water supply is limited or non existent, consider using two pumpers or other means such a water tender, to augment the ______ to the pumper.
Water supply
Remember, for offensive operations, a minimum _____ must be capable of supplying the calculated rate of flow plus back up lines and other lines used to protect exposures
Water supply layout
During large scale incidents apparatus are often assigned to a
Staging area
