Ch 13 Vertical Ventilation Flashcards
Before stepping onto any roof, firefighters she_____ and _____ the roof and they should continue to do so as long as they are on the roof
Sound, read
Firefighters should sound every roof with a hand tool as they advance, except for roofs covered with _______ or________
Tile, slate
To ________ A roof means to observe the roof, construction features, and other indicators that can warn firefighters of potentially unsafe conditions
Read
Because Vince, skylights, and other features penetrate a roof _________ the rafters or joist, they can offer other clues to the location and orientation of roof supports
Between
Firefighters should ______ the roof with the blunt end of a pike Pole, rubbish hook, or axe any time they attempt access
Sound
Roofs covered with _____ or _____ cannot be sounded and the individual pieces must be removed to reveal the underlying structure
Tile,slate
______ ladders should only be used to give the fire fighter more secure footing on pitched roofs
Roof
To prevent spot fires downwind of the burning building, a fire stream may also be used to cool the thermal column rising from the ventilation exit opening. When fire streams are used for this purpose, it is important that the stream be directed ______ or at a slightly upper angle across the opening but never into the exit opening itself
Horizontally
Once firefighters are on the roof, they should test the roof by gently_____ on it while holding onto the ladder or parapet wall with one hand
Bouncing
most roof assemblies employ a _____ system with rafters spaced from 12 to 24 inches on center, spanning the shortest distance between structural members or bearing walls
Parallel rafter
If sounding does not reveal the location and direction of the rafters, a diagonal cut through the roof covering can be made with a chainsaw or rotary saw at an angle of____ degrees to any exterior wall
45
a triangular hole, also known as an _______, can be completed to determine spacing, roof thickness and possible fire conditions in the attic
Inspection hole
While departmental SOP‘s must always be followed, it is recommended that a clear space of at least_____ be maintained in all directions from anyone using a cutting tool in vertical ventilation
10 feet
chainsaws used for forcible entry or ventilation are usually equipped with ______ chains to allow cutting through nails and light gauge metal components
Carbide tipped
The cutting procedure used with chainsaws is very similar to that used with rotary saws. One difference is that the operator should first make sure that the ________is working
Chain Oiler
To be most effective, a chainsaw must be used with the bar at a _______angle to the roof surface
Right
Cutting a roof with an_____ should be done as close to the rafters as possible to minimize the tendency of the roof surface to deflect when struck
Axe
Pike poles can be used to strip roofing in much the same way as pick headed axes are used. The hook is inserted into the___________, and the roofing is pulled back
Leeward crosscut
In the roof construction nomenclature, the angle or degree of slope is called the________
Pitch
______ roofs are usually supported by wooden or metal rafters, laminated beams, or engineered trusses spanning the shortest distance between bearing walls
Pitched
The most common examples of _____ roofs are the gable, hip, lantern, and shed styles
Pitched
All rafters in hip roofs run_____ to the nearest outside wall
Perpendicular
The _______ roof consist of a high gabled roof with a vertical wall above a downward pitched shed roof section on either side
Lantern
The______ roof can be seen as half of a gable roof or as a slightly pitched flat roof sloped in one direction only usually from the front of the building down to the back
Shed
_______ trusses heavy duty trusses with sloping ends
Bridge
The______ roof has a double slope on each of its four sides
Mansard
The _______ roof includes characteristics of both flat and pitch roofs; four steeply sloped sides rise to meet a flat top call a deck
Modern mansard
A _____roof is most often found on barns and other outbuildings
Gambrel
The ______ roof may be seen as two opposing shed roofs that meet at their lower edges in the middle of the building
Butterfly
_______ roofs are designed to shed rain and snow, so their main hazards are steepness and the lack of secure footing for firefighters working on them
Pitched
Pitched roof’s should be vented at the highest point on the______ side directly over the fire or as close to it as safely possible
Leeward
In many areas, flat roofs are more common on Mercantile and industrial buildings, multiple dwellings, and apartment complexes then on single-family dwellings. This type of roof ordinarily has a slight slope of______ or less from the front toward the rear of the building to allow drainage
Two-twelve pitch
Flat roofs are commonly supported by______ joists or rafters similar to the joist used in floor systems
Horizontal
Because it is difficult and time-consuming to cut concrete roofs that are more than _______thick, they are often designed with built-in access panels that can be lifted out in an emergency
4 inches
Poured gypsum roofs consist of bar joist or I-beams with brackets welded to the Joists. gypsum board is placed on the brackets and is covered with a layer of gypsum cement up to _____inches thick to which wire mesh reinforcement is added
2 1/2
A _______ roof will often reveal itself when the vent pipes that penetrate the roof appear to be taller than usual
Sagging
_______ roofs may be supported with bowstring trusses, or arches of steel, concrete, or laminated wood
Arched
Steel arches can be made from plate girders or trusses. Typically, arches are spaced at _____to_____ foot centers
16,20
The ________ Truss roof, commonly found in older buildings houses a variety of commercial or industrial occupancy‘s, uses an arch with a wooden or metal bottom cord
Bowstring
The ________ Arch roof uses massive arches of steel, concrete, or laminated wood buttressed into the ground at each end
Trussless
the _____ Roof is another type of trustless arch made up of interlocking geometric framework on which plank sheeting is laid
Lamella
________ roof construction consist of laminated beams of various sizes commonly 6 x 36“ to span the length or width of the building
Panelized
A three layer, laminated insulation paper is sometimes used on the underside of_______ decking
Panelized roof
All trusses also have a top chord and a bottom cord, connected by other components known as the_______
Web
The bridging effect of parallel chord trusses causes the top cord to always be in ____ and the bottom chord in _____
Compression, tension
Some parallel chord trusses are constructed of wooden components held together with sheet metal gusset plates, also known as _______
Gang nails
Common ________ roof truss configurations are the Howe, Pratt, and Fink trusses
Pitched
Like many parallel chord trusses, the most common pitched roof trusses are pre-fabricated of relatively small dimension wood, usually_____ inch lumber held together with metal gusset plates were the components intersect
2x4
___________ consist of three main components; a top chord, a bottom chord, and a solid 3/8in inch plywood or OSB web
Wooden I-beams
The most common substrate is _______, also called roofing felt
Tar paper
Roof coverings are classified in NFPA _______, guidelines on roof coverings and roof deck construction
203
______ and ____ shingles are the most common because of their appearance and inherent durability
Cedar, redwood
Shakes and shingles are usually nailed to wooden 1x 4 inch or 1 x 6“ _______ with a space of about 1 inch between the planks
Plank sheathing
Composition roofing also comes in a variety of materials and shapes. The most common forms are _______ and rolls of various widths
Shingles
_____and______ Roof coverings are very common on flat or nearly flat roofs
Tar, gravel
_________. Wooden strips fastened to a wall, floor, or ceiling for the purpose of attaching a finishing material
Furring strips
________ are normally square or rectangular metal covered hatches that provide an exit from an attic or cockloft onto the roof and are often accessed from the top floor or the attic by a ladder
Scuttle hatches
______ Vents are square or rectangular structures that penetrate the roofs of a single story building to provide additional natural light and Ventilation
Monitor
Cutting ______ is often the fastest and most efficient way of opening a roof
Louver Vents
A second method of louver venting, sometimes called rolling the rafters, involves making the two longest cuts_______ to the rafters
Perpendicular
Primarily a defense maneuver,_______ is sometimes referred to as strip ventilation
Trench ventilation
When creating an opening for ________ventilation, firefighters should only cut the roof covering and sheathing and not the members supporting the roof
Trench
_________ has proven to be particularly effective in limiting the spread of attic fires in strip malls and other buildings that have long, narrow, common attics
Trench ventilation
___________ is accomplished by cutting and opening in the roof, at least 4 feet wide, across the entire width of the building
Trench ventilation
Firefighters should never get on a roof wearing anything less than full protective clothing, SCBA and a pass device. As a minimum, the vent group leader should also be equipped with a _____
Portable radio
An ______ is often the safest and most efficient means of gaining access to a roof and should be positioned to gain the greatest advantage possible
Aerial device
In general, the strongest points of any roof are where the roof meets the outside walls, directly over roof supports, and at ridges or valleys. The weakest points are_________
Between the supports
Because roof supports always run ______ to the outside walls, firefighters should never walk diagonally across the roof of a burning building
Perpendicular
The most common examples of _____ roofs are the gable, hip, lantern, and shed styles
Pitched
In the past, this type of roof was often used in industrial and institutional buildings to maximize natural light and ventilation it is rarely seen in modern buildings
Sawtooth roof
In addition to the hazards presented by the pitch or slope of the roof and by falling debris, the growing use of lightweight roof trusses can present an equally serious hazard to firefighters. These assemblies are often held together only with metal _______that can warp and pull out of the wood when exposed to direct flame impingement
Gusset plates
____— arches can be made from plate girders or trusses
Steel
When 10 to 20% of a _______ roof burns away, sudden failure of the remainder of the roof is likely
Lamella
The most common type of roof trusses are parallel chord trusses and ______ trusses
Pitched roof
The ______ effect of parallel chord trusses causes the top chord to always be in compression and the bottom chord in tension
Bridging
Common pitched roof truss configurations are the _______,________and ________
Howe, Pratt, fink
One 8 x 8‘ opening is equal in area to________ holes
Four 4x4
______&________ reduce the chances of firefighters getting on or remaining on a roof that is structurally unstable
Reading, sounding
Whenever firefighters are on a roof, the building should be laddered on ______
At least two sides
Because Vents, skylights, and other features penetrate a roof between the rafters or joist, they can offer other clues to the________
Location and orientation of roof support
The positioning of skylights can indicate the location of ________
Roof supports
Firefighters should _____ the roof if possible with the blunt end of a pike pole, rubbish shook, or ax anytime the attempt access
Sound
In general, the strongest points of any roof are where the roof meets the outside walls, directly over _______, and ______
Roof support, ridges or valleys
Firefighters can reduce the risk of falling through a fire weakened roof by walking only over________
Roof supports
If the structural integrity of the roof is in question, it is often best to ventilate from_______
An aerial device
If a stream is directed into a ventilation exit opening, it will counteract the _______ and push steam and smoke down into the building toward any firefighters working inside
Natural convection currents
When firefighters reach the point where the ventilation opening is to be made, every cutting and pulling operation should allow them to continually work from the _____ toward the _______
Involved area back, uninvolved area
When ventilating any roof begin the ventilation opening on the ______ and back toward the wind so that the smoke in hot gases are blown away from the vent crew
Leeward side
The most common cutting tools used for vertical ventilation are the ____,_____ and the ______
Rotary saw, chainsaw, pick head axe
Chainsaws used for forcible entry or ventilation are usually equipped with ______ to allow cutting through nails and light gauge metal components
Carbide tipped chains
To keep both hands free for other work, some firefighters wear their axes in _______strapped around their waist
Scabbard
While some fire departments have designed their own special stripping tools, the most common ones are the ______,______ and the _______
Pick head axe, pike pole, rubbish shook
The slopes of pitched roofs often vary with climate and aesthetic considerations. The pitch is expressed in ________
Inches of fall per horizontal foot
The most common examples of pitched roofs are the ______,______,____ and the_______
Gable , hip, lantern, shed
Inverted roofs differ from conventional flat roofs primarily in the location of their________
Main roof beams
From the outside, an inverted roof looks like any other flat roof, but the surface may feel _____ to anyone walking on it
Springy or spongy
The design of the ______roof often creates a concealed space several feet in height between the ceiling and the roof deck
Inverted
Very similar to an inverted roof is the so-called rain roof, this can be found over any type of roof, it is most common on buildings with ____ or _____ roofs
Flat, arched
This type of roof has characteristics of both pitched and flat roofs
Modern mansard roof
Ventilation holes in flat roofs should be cut _____ to the rafters and _____ to the outside walls of the building
Parallel, perpendicular
While a conventional square or rectangular ventilation opening may span several rafters, ______only leave one rafter in the center
Louver vents
When glass skylights must be broken, firefighters should break a ______ first and pause before breaking out the remaining panes
Single pane
_____ are typically used to support roofs that must span large, open spaces unsupported by pillars or post
Arches
Both ____&______ forces continuously act on an arched roof
Horizontal, vertical
These roofs incorporate the same or similar top cord as the truss roofs, but steel tie rods are used instead of bottom cords for lateral support with turnbuckles to maintain proper tension
Bowstring arch roof 
Concrete, clay, or ceramic tile roofs use tiles that are usually flat, interlocking pieces that hook over 1 x 2“ inch battens sometimes called _______, nailed to the sheathing or directly to the rafters
Furring strips
Tile and slate roofs are somewhat fragile and often cannot be walked on without breaking the tiles. To reduce breakage, firefighters should step only on the________ of the tiles, and they may spread their weight by working from roof ladders
Lower half
This type of roof covering consist of aluminum, fiberglass, or 18 to 20 gauge steel panels over a wooden or metal substructure
Light gauge metal or fiberglass
These structures usually enclose the top of stairways that terminate on the roof, and they usually have a metal clad exterior door of standard size
Penthouses (bulkheads)
Some residential and small office buildings have a horizontal row of windows installed on a vertical wall between to offset roof sections
Clerestory windows
Primarily a defensive maneuver, trench ventilation is sometimes referred to as____-
Strip ventilation
In most cases a _____ cut is fastest for making a trench vent
Center rafter (louver)
Wooden deck roofs may present a hazard if light weight plywood or OSB is used. Panels of ___to ___ inch thickness offer a little fire resistance, but may be difficult to remove for tactical ventilation
3/8, 5/8
Trench ventilation is accomplished by cutting an opening in the roof at least _____ wide across the entire width of the building
4 feet
