NORMAN - Ch 9
Insulspan panels typically come in: (p 266)
8' widths and are up to 24' in length.
When you begin you ventilation efforts, the fresh air being drawn toward the nozzle can: (p 250)
cause this smoldering material to burst back into flame, drawing all the heat and smoke right past the nozzle team. If practical, keep the fire between the nozzle and the vent point until you are sure there is little danger from this fanned rekindle.
Before starting the fan (PPV), the IC should know the answers to the following: (p 253)
Where is the life hazard, including searching FFs? What is the location and extent of the fire? is it in any void spaces? What is the status of all hoselines? Are they operating or ready to operate? What degree of confinement is present? If the fire is already largely self vented, PPV may not be useful. What exhaust openings are available or can be created? What PPV equipment is available? Will the power supply create any issues at the command post? What environmental factors exist in the vicinity of the fan? Dust, powders, weeds, or other materials that might be drawn into the fan, damaging or impeding operations.
In cases where exposed roof joists were unacceptable for reasons of aesthetics and energy conservation, a: (p 258)
ceiling has typically been added, usually a wooden framework suspended several feet below the roof from light wooden hangers.
Joists act as _________, and the more bays you open, the: (p 262)
a draft curtain; faster things will clear up. Keep the wind at your back.
A parapet wall usually does indicate: (p 274)
a fire wall
When opening a bulkhead door on the roof of a building, you should: (p 254)
check inside the door for trapped occupants as the first action upon reaching the roof.
A working fire on the top floor of any large-area flat-roof building requires: ( 258)
an immediate commitment of at least 4 members equipped w/ 2 power saws, 2 -6 or 8 foot hooks (take 10'ers for larger building, which may have a cockloft as much as 5 feet deep), a halligan tool, an axe and a portable radio.
The OV team is responsible for: (p 247)
an immediate exterior survey of the structure, locating victims, locating the seat of the fire, and creating FF escape routes.
Having a hoseline on the roof to__________ is highly recommended. Operating a hoseline into any ventilation opening, however, must be__________. (p 263)
control fire from spreading across the entire roof surface; strictly forbidden
Fire in either the cockloft or the occupied floor below may be readily vented by: (p 258)
cutting a hole directly over the fire and pushing down the ceiling. This action is absolutely critical once fire has entered the concealed space, for there is no other means of venting this area.
The trench cut is a _________ tactic. It must be used in conjunction with: (p 267)
defensive; a vent hole. Primary vent hole must be cut first.
The key to success for the entire operation on a rain roof: (p 265)
depends on the roof team recognizing the presence of the rain roof early enough to permit deployment of a hose stream to this area.
Never ventilate where you will create a __________ problem. (p 271)
exposure. Horizontal and vertical ventilation can both be problems if fire venting from the opening exposes nearby people or buildings.
If further expansion of a roof cut is need, it is generally better to: (p 262)
extend an existing cut that it is to start a new one.
Probably the greatest danger FFs engaged in roof ventilation is the: (p 272)
fellow firefighter. particularly the member handling the power saw, but it could also be the member w/ the axe, hook, or any other moving object in conditions of poor visibility.
"Textbook ventilation" (opening the windows) creates only: (p 242-243)
half the window opening that breaking double-hung windows does.
The _______ the nozzle pressure, the ________ air that is moved. (p 249)
higher; more
Window venting is the most suitable type of ventilation for most fires in: (p 244)
houses and similar-size structures that have high window-to-room-size ratios.
Thinking that ventilation is not as important as it was in the past because FFs have SCBA's and can breath has several problems: (p 242)
it totally ignores any victims who might still be in the building, and it assumes that the FF's masks will always protect them. Third, the buildup of heat that results when venting is't prompt and effect-- results in flashover. fourth: BUILDINGS ARE BEING MADE TIGHTER AND TIGHTER--potential for backdraft explosions is increasing w/ every bit of insulation.
The _____ is the simplest, fastest type of examination hole possible. It is also: (p 259)
kerf; easily repaired if fire doesn't severely damage the roof. It is made simply by plunging the saw through the roof and then pulling it out. This creates an opening about 1/4 in wide by 10 in long. Although quickly made, it often isn't a very positive indicator of fire, since the opening is so narrow that it doesn't allow you to view the areas on either side. If there is fire directly below the hole, it will show through, but fire on either side may not be visible.
The sequence of cuts needed to produce an 8x8ft opening must be: (p 260)
logically planned so that members making the later parts of the hole won't be downwind of the earlier segments where heat, smoke, or fire might prevent them from completing their tasks.
By heating up the products of combustion, the fire has made its by-products rather mobile. All we have to do is: (p 249)
open doors, windows or skylights, and the smoke will readily pour out. This is called natural ventilation.
Insulspan panels require very little ___________, thus spanning an area as large as ______ without ________. (p 266)
other support; 24', joists.
The second most common vertical avenue is the: (p 255)
pipe chase
FFs will have great difficulty locating, opening, and attack fires in void spaces because of: (p 256)
poor visibility (very smokey). The answer is total ventilation. This includes venting all window and other horizontal openings, as well as roof ventilation, particularly over the top of vertical voids.
Ventilation can be defined as the process of: (p 242)
removing the toxic products of combustion and replacing them w/ fresh air.- Ventilation is an ongoing battle between the fire and the FFs for control of the building.
Experimentation has proved that putting a positive pressure in a stairwell, the flow of heated gas can be: (p 251)
reversed, enabling attack crew to gain a foothold on the fire floor.
Generally, before there is any danger of supporting joists succumbing to fire, the __________ will have burned through first. (p 258)
roof boards (1x6 planks)
Peaked roof, found on many private homes, are usually much more easily vented by: (p 248)
smashing window in the gable ends or dormers than by cutting the roof itself.
Another concern for all members, added to the roof is _____________. It is typically encountered in high value occupancies, such as jewelry and appliance stores, gun shops, and especially in high crime neighborhoods. It consists of: (p 272-273)
steel plating; 4x8' sheets of steel, from 1/8 - 1/4" thick.
Be sure whenever venting windows in the fire area: (p 258)
that the wind won't be blowing inward and fanning the flames.
To be most successful with at trench cut: (p 267)
the ceiling below the roof opening must be pushed down for the entire length and width of the cut, removing as much fuel in the fire's path as possible.
If you try to stand up to open a window for ventilation, and are driven back down by heat: (p 244)
the glass should be broken WHEN THE HOSELINE IS CHARGED.
Cutting an inverted roof should proceed in: (p 264)
the same way as cutting a standard roof. Use extra caution to avoid making too deep a cut, therby severing parts of the 2x4 framework.
Other factors that influence the choice of vertical or horizontal ventilation, or both, include: (p 248)
the size and location of the fire, the construction of the building, the available staffing, and the effects of weather, particularly wind.
Even if the fire appears confined to a lower floor, you should take immediate steps to fight it on the the top floor or in the attic if: ( p 255)
the soil pipe on the roof feels hot to the touch. A hoseline must be stretched, the top-floor ceilings must be pulled, and if fire is present, the roof must be opened.
The most common vertical artery is: (p 254)
the stair case.
Generally, there are two types of old-style flat roofs: (p 256)
the standard flat roof, where the main roof joists are right at the roof level, w/ their roof boards nailed directly to the joist; and the inverted roof, where the roof boars are nailed to a framework of 2x4's, raised several feet above the main roof joists.
Immediately upon reaching the roof, the members should: (p 258)
vent any vertical shaft they find such as bulkhead doors and skylights.
Several dangers of a rain roof: (p 264)
1. the added weight was never designed into the original roof supports, which may be approaching the point of failure. 2. the two layers can substantially delay, or even prevent, venting. 3. the multiple layers create multiple void spaces where fire may be hiding.
Problems w/ insulspan panels: (p 266)
1. the nature of the product (styrofoam insuation is highly combustible, producing tremendous quantities of toxic smoke and intense flame; and the OSB is also combustible.) 2. thickness. units being installed in Brookly, NY, are as much as 8.5" thick. The typical 12" circular saw has a depth of cut of only 4", rendering typical ventilation techniques impossible.
Timbers of old style flat roofs are limited in length to about a ____ft span between supports, most often a ______wall or _________. Nailed directly to the roof beams is the __________, usually __________. This is generally covered by several overlapping layers of_________. (p 257)
20'; masonry wall or steel I-beam. roof decking; 1x6" tongue in groove planking; tar paper.
Older flat roofs have wooden beams of ______, or even ______, as main support beams. Typically, these are spaced _____inches apart and can carry nearly the same load as the floor joists below them. (p 256)
2x10; 3x12; 16 inches
When you encounter energy efficient windows, undertake window venting: (p 245)
ASAP while the attack team is in a safe area, preferably behind a closed door. If this isn't possible, it may be desirable to delay venting until after the hose stream has thoroughly cooled the fire area.
Critical items for the roof team to report to the IC: (p 276)
Any visible life hazards Size and shape of the building, particularly depth, which may not be visible from the street. Construction of the roof, paying particular attention to trusses. Condition of roof Fire showing through the roof Threatened exposures Weights resting on the roof Location of parapet walls Shafts w/in the building Setbacks, or extensions that are not visible from the street.
Opening or breaking a window decisions should be based on: (p 244)
First, have an idea of the progress of fire control and search efforts; second, consider that conditions will get worse before they get better.
Draw backs of using a hose stream for ventilation:
It can't be used at minor fires where water damage is a concern. In areas of poor water supply, the drain of using part of the available water to move smoke may mean running short of water for fire control. Should not be used in area of below-freezing temperatures if the spray will land where the resulting ice could create fall hazards.
______________ structures such as_____________ and_____________, having a sizable body of fire already in the cockloft, don't generally benefit from trench cuts, since the length of cut needed to go from wall to wall demands so much cutting that it is impractical. (p 271)
Large area; supermarkets and taxpayers. These buildings are better fought by putting all available saws to work cutting multiple large vent holes over the fire so that hoseline crews can put the fire out.
When planning a roof cut, the considerations are: (p 260-261)
Means of escape from the roof if things go badly; second, when positioning the cut is the wind direction.
__________can involve hoselines portable fans, or building ventilation systems, depending on the resources available and the fire situation. (p 249)
Mechanical Ventilation
PPV has decided advantages over negative pressure: (p 251-252)
The first is efficiency- a fan blowing in can move almost twice the volume of smoke as compared to the negative mode, especially if churning occurs. Since fans are set back from the doorways, they don't clutter the access routes. They have a ready ability to remove flammable vapors safely- natural gas/propane, etc.
Disadvantages of PPV: (p 252-253)
The most serious being the danger of fanning a smoldering fire into a serious conflagration. IF THE FIRE IS IN A CONCEALED SPACE, HOWEVER, IT MAY NOT BE POSSIBLE TO EXPOSE IT AND DARKEN IT DOWN FAST ENOUGH TO PREVENT CONSIDERABLE EXTENSION. PPV must not be used if FFs are entering the building from any point other that where the fan is operating. The fan can provide fresh air to trapped occupants, but if there is an exhaust opening in their vicinity, there is a risk of blowing any fire between the victims and the fan right at the victims.
Early recognition of the presence of an inverted roof, plus understanding of how one behaves under fire conditions, will allow: (p 264)
members on the roof to evaluate more realistically just how bad the conditions are.
In old style flat roofs, during construction, the entire roof surface was then: (p 257-258)
mopped w/ hot tar to seal it. In some cases, gravel was then spread over the hot tar to act as a retardant to the spread of flames.
A trench cut is: (p 270)
not an offensive ventilation hole but rather a defensive, home built fire stop. As such, using hoselines through this type of opening is absolutely acceptable.
The most important concept to remember when discussing ventilation is that it must be: (p 244)
of sufficient volume to win the battle w/ the fire.
In buildings w/ modern double or triple pane, energy-efficient glass, you must create an exception to the break or open sequence. In this case: (p 245)
the sudden admission of oxygen as the attack crew enters can have catastrophic results. Extremely rapid fire growth or even backdraft is possible.
When distinguishing between venting for fire and venting for life, the key factor is: (p 243)
the timing of the ventilation. Venting for life should obviously begin as soon as the life hazard is recognized.
The primary factor in H, E, and O shaped buildings is: (p 267)
they all have a common cockloft over all the wings.
The most logical place to cut an extending fire off is in the _________area, where the narrowness of the opening allows a limited number of personnel to fight a holding action w/o being outflanked by fire. (p 267)
throat
The pattern that moves the most air from an area is one that is: ( p 249)
tight enough to move the stream and gas out of the area yet wide enough to entrain large amounts of air. Generally, this is in a range of about 30* fog pattern.
The first step in making any ventilation opening is: (p 259)
to locate the proper site, usually as close to directly over the fire as is safe.
The best way to breach Lexan (polycarbonate) sandwiched panes of glass is: (p 247)
to use a circular saw w/ standard carbide-tipped blade if available. If a saw is not available, it is possible to cut through this type of window using the blade of an axe. (car windshield method) Avoid striking the glass at a 90* angle. THE LAST THING YOU WANT TO DO IS TO DRIVE THE HEAD OF THE AXE COMPLETELY THROUGH THE GLASS, BECAUSE IT GETS STUCK EASILY AND IS DIFFICULT TO PULL BACK THROUGH.
A serious fire in ___________or__________demands roof ventilation if the fire is to be extinguished from the interior. (p 248 fig 9-5)
top floor or cockloft
Two types of inspection holes: (p 259)
triangular or kerf cut
The immediate assignment of one or members to ___________________ from the outside is a exceptionally important assignment to be made. After placement of the initial attack hoseline and designation of an interior search team, quite possibly the next most crucial position to be covered is the ________________. (p 246)
vent the fire-area windows; Outside Ventilation (OV) team.
If a person is reported to be in a room adjacent to the fire area: (p 243)
venting the windows will allow an influx of fresh air to someone whose life depends on it. Still, if you don't immediately take steps to remove that victim, you may worsen his/her plight by drawing fire toward the vent window. Generally, horizontal ventilation for a life hazard must be coupled w/ an immediate rescue effort.
2 main reasons for performing ventilation: (p 242)
venting to allow attack teams to enter and operate w/in the structure (venting for fire), and venting a specific area to provide fresh air for breathing and to improve visibility while searching (venting for life)
Immediate __________ has saved hundreds of lives by preventing mushrooming and drawing fire away from victims. It should be a primary tactic at most: (p 243)
vertical ventilation; low-rise, nonfireproof multiple dwellings.