Book 29: Ventilation Techniques Flashcards
What is ventilation?
Ventilation is the “systematic” removal of heat, smoke, and fire gases from a structure, and replacing it with cooler, clean, fresh air.
Effective ventilation will accomplish what four main objectives?
- Save lives.
- Assist in firefighter access.
- Control the horizontal spread of fire.
- Reduce the possibility of flashover and backdraft.
If the heat, smoke, and fire gases are not released, they will accumulate at the highest point of the structure and begin to bank down and spread laterally. This process is generally known as
Mushrooming
_____is a condition where all of the contents of a room are heated to their ignition temperature. Once their ignition temperature is reached, the entire room will quickly be involved in flames.
Flashover
According to book 29, how many firefighter deaths are attributed to flashover?
100 deaths on average 85 due to flashover
In a confined area, if the structure’s contents reach their ignition temperature and there is not sufficient oxygen to support combustion; all that is needed is an air (oxygen) supply to explosively change the superheated area into an instant inferno. This condition is best known as ______
Backdraft
What are the two types of ventilation
Horizontal and vertical ventilation
____ _____is the systematic removal of heat, smoke, and fire gases through wall openings such as doors and windows.
Horizontal ventilation
What two methods are performed with horizontal ventilation?
Natural and positive pressure ventilation.
_____ _____is easily done by opening doors and windows and allowing the wind to ventilate the building.
Natural ventilation
_____ ______ ______is a method of forcing clean, fresh, pressurized air into a structure with blowers. By systematically opening doors and windows to channel the pressurized clean air, you can effectively ventilate smoke out of a structure.
Positive pressure ventilation
______ ______is the opening of the roof or existing roof openings (skylights, hatch covers, etc.) for the purpose of allowing heat, smoke, and fire gases to escape from the structure into the atmosphere.
Verticals ventilation
What are the 2 types of ventilation holes?
Heat Hole (Offensive) Strip Ventilation (Defensive).
A ____ _____ is a hole placed directly over the fire or as close to the fire as safety will allow.
Heat hole
When cutting on a lightweight roof should employ what practice?
“trading space for time”
____ _____helps to stop the horizontal spread of fire. must be done in conjunction with a heat hole.
Strip ventilation
_____ _____ ___is a technique used when cutting plywood sheathing (4 cuts). Center rafter provides the largest hole possible with the ______amount of cuts.
Center rafter cut
Minimum
_____is the material used to comprise the base and exterior covering for the roof. The base material can consist of solid wood sheathing, plywood-type materials, corrugated metal, and other materials
Decking
Plywood sheathing is installed so that the __’ dimension of the plywood crosses the rafters or joists and the __’ dimension parallels the rafters or joists. The sheets of plywood are then staggered much like a brick or block wall. This is called
8’
4’
Diaphragm nailing
____ ____ are made parallel to ____with no concern to locating rafters.
Dice cuts
Rafters
___ _____ are metal clips used to hold the butted ends of plywood together. They are common on _____roofs.
“H” clips
Pitched
____ __ ____is a cut made through the roof decking that is made perpendicular to rafters. This cut is used to locate _____This cut involves ______ rafters. must be done on roofs covered with ______ and _______ _______. This cut is usually the first cut made on a _____ _____ ____.
A head cut
Rafter
Rolling
Plywood and diagonal sheathing
Center rafter cut
____ _____ _____motion brings the pulling tool under and up to the decking in a smooth, forceful motion that will separate the decking materials from the rafters.
The “J” hook
____ _____ ____ is a single cut made through the roof decking, the same width as the ____ ____ ____. Although not as effective, the kerf cut can be used as an alternative to using the _____ _____ _____.
A kerf cut
Chain saw lade
Smoke indicator hole
Where should ground ladders be thrown?
Uninvolved corners of the structure.
A minimum of _ ladders should be thrown to an involved structure
2
Once all 4 cuts are complete, use a rubbish hook and push down on the ____ side (the side closest to your _____and pull on the far side. This method is used with the center rafter louver technique. This is?
Near side
Ladder
Louver
_____ _____ are usually made from a 2” x 4” laid flat between rafters to provide a nailing surface for the edge of the plywood sheathing. Since the plywood normally used is _’ x _’ in size, a nailing block will usually be found every __feet.
Nailing blocks
4’x8’
4 feet
A cut through the roof decking made parallel to the roof rafters.
Parallel cut
A door leading from the interior stairwell to the roof.
Penthouse door
____ ____is a small triangular piece of roof covering (composition), which is removed from the roof to expose the roof sheathing.
A plug cut
Rolling rafters is used to make___?
A head cut
_____ _____ ___is a light cut of the roof covering, usually composition only. This cut is used to facilitate the removal of multiple layers of ______ ______(______).
A score cut
Roofing material (composition)
___ ____ ____is a light cut made with the chain saw, cutting through the roof covering and plywood sheathing. The saw is not inserted deep enough to cut through the ______. You “___” over the top of the rafters.
A skim cut
Rafters
Skim
_____ ____ when used in conjunction with an offensive ventilation hole (heat hole), can help stop the horizontal spread of fire.
Strip ventilation
With conventional construction, if time and safety permits, the roof team “___” cut the heat hole directly ____ ___ ____
Will
Over the fire
When operating on a ____ ____ ___roof (or suspected lightweight truss), the ventilation team shall never conduct ventilation operations directly over the fire.
Lightweight truss roof
On a lightweight truss roof, Members should employ the practice of “_____ ____ ___ _____” so that they may complete their roof-cutting operation prior to the fire impinging on a given ventilation hole.
Trading space for time
On roofs sheathed with plywood, the “Head Cut” is made _______ to rafters. You need to know ____ ______ in order to accomplish any Heat Hole or Strip Ventilation Hole.
Perpendicular
Rafter direction
A properly placed heat hole saves lives and will allow firefighter access by reducing____, _____, and ____ ____inside the structure.
Heat smoke and fire gases
A____ _____ will also reduce the possibility of backdraft and flashover, and will slow down the _______ spread of fire.
Heat hole
Horizontall spread
A strip ventilation hole should be placed ____ ____of the fire, and the strip ventilation hole should extend the entire _____ of the building, creating a _______
Well ahead
Width
Firebreak
Center rafter can also be used for cutting strip ventilation on _” x _”or _” x _” sheathed roofs.
1’’x4’’
Or 1’’x6’’
Ground ladders should be thrown to the _______ _____ of the structure.
Uninvolved corners
The exception to the rule of throwing ladders the the uninvolved section is?
Roof ladders
For roof ventilation, a “MINIMUM” of ___ ladders should be thrown to the involved structure.
Two
A plug cut is used to determine ____type and ______ _______ ______.
Shearing type and roof composition thickness
______ _____ _____and ____ _____ _____are all materials used for floor and roof decking. The normal and most common size for plywood is 4’ x 8’. Under fire conditions, plywood burns at a quicker rate than solid wood sheathing and plywood _______
Plywood, chip board, and oriented strand board
Delaminates
are usually constructed from glass or plastic. On apartment buildings, will be placed over hallways and stairwells.
Skylights
On commercial buildings skylights are placed over ____ ____
Manufacturing areas
When using skylights in conjunction with roof ventilation, it is imperative that you ________ remove skylights.
Systematically remove
Remove skylights in the same ______ and order as you would cut ____ _____.
Direction
Ventilation holes
a small triangular hole cut through the roof decking (sheathing and roofing material) made with the chain saw or an axe.
Smoke indicator hole
A smoke indicator hole is used to indicate ____and ____ conditions directly below the indicator hole.
Smoke and fire conditions
Smoke indicator holes should be placed along the path of _____or _____ every ___ ____.
Access or egress every few yards
Placing smoke indicator holes in the path of the fire can monitor
Fire spread
Smoke indicator holes can be placed on roofs of buildings attached to fire buildings to indicate _____ _____
Interior exposure
a technique used to assist the roof team to safely walk on a roof.
Sounding
Sounding utilizes a long-handled tool (____ ____/____ _____) used to hit the roof.
Rubbish hook/pike pole
Because of its weight and reach, a long-handled _____ _____ is superior to, and recommended over, a ____ ___ ____ as a sounding tool.
Rubbish hook
Pick head axe
are placed on roofs to ventilate attics and building interiors.
Turbine ventilator
ventilators are working correctly, ____ _____ _____. A turbine-style ventilator is about __% more effective when the turbine is spinning.
Leave them alone
30%
are plumbing pipes that extend from inside the structure through the roofline.
Vent pipes
Vent pipes can be constructed from ____ ______, ______ ____, or _____ ____.
ABS plastic
Cast iron, steel pipe
____ ____ ___ is a series of two cuts used to identify rafter direction “ONLY.”
45 degree cut
The first 45-degree angle cut is made toward or away from any _____ _____. A 45-degree cut will ensure the saw will ______ a structural member.
Exterior wall
Intersect
45 degree cut:
When you hit a rafter, “___.” Make a second cut ______ or _______ to the exterior wall.
Stop
Parallel or perpendicular
If rafter type and rafter direction are unknown, a ___ _____ ______ cut will tell you rafter type and rafter direction, the _____type, the _______ of roof composition and when complete, it can act as a ____ ______ hole.
45 degree inspection cut
Sheathing type
Thickness
Smoke indicator hole
A 45-degree cut will ensure the saw will intersect a structural member. When the saw makes contact with a rafter, ___ over the rafter and continue the cut for approximately _ to __ inches.
Roll the rafter
6-10’’
This technique is used for cutting 1” x 4” or 1” x 6” solid, spaced, or diagonal sheathed roofs.
Dicing
Dicing has many advantages. First, it is _______. The roof team will always be working back toward their ______. The roof team can work __________. After the chain saw operator makes the ____ cut, the puller can start pulling boards, and the chain saw operator can continue cutting the roof.
Directional
Ladder
Simultaneously
Third
Dicing does not require the cutter to know the exact _____of the rafters. _____ type and ______ are all that is required to be known.
Location
Rafter type and direction
Dicing:
If needed, the first cut performed in this operation is a ____ ____ or ____ ____
Score cut or head cut
Dicing:
The length of the dice cut is determined by the _____ of the tool being used to pull the sheathing (pick-head axe, rubbish hook)
Reach
Always leave a minimum of ____un-pulled section between the cutter and the puller.
One
Center rafter louver:
The head cut is started by first cutting ____ from your ladder to locate your first “_____” rafter.
Away
Outside
Center rafter louver:
Reverse directions, and cut back _____your ladder. Roll the second “_____” rafter and ____ at the third “inside” rafter.
Towards center
Stop
Center rafter louver:
Move back to the first “outside” rafter and cut a _____ cut approximately _ to _ inches _____ the rafter.
Parallel
2-3’’
Inside
Make the ____ cut, cutting towards the ladder. Start at the first “_____” rafter, roll over the second “_____” rafter, and stop at the third “____” rafter.
Bottom cut
Outside
Center
Inside
Make a parallel cut approximately _ to _ inches inside the ____ “inside” rafter. Then louver section.
2-3’’
Third
EXPANDED CENTER RAFTER LOUVER WITH CONSTRUCTION:
Move back to the first “_____” rafter, and make a _____ cut approximately __ to __ inches inside the rafter.
Outside
Parallel cut
2 to 3’’
CENTER RAFTER LOUVER AGAINST CONSTRUCTION
The head cut is started by first cutting ______ from your ladder to locate your first “______” rafter.
Away
Outside
CENTER RAFTER LOUVER AGAINST CONSTRUCTION:
Reverse directions and cut back ______ your ladder. ___ rafters. Make “______” as long as intended hole.
Towards roll
Head cut
CENTER RAFTER LOUVER AGAINST CONSTRUCTION
Move back to the first “_____” rafter and make a _____ cut approximately _ to _ inches _____ the rafter. Make parallel cut approximately ____ feet long.
Outside Parallel 2-3’’ Inside 3 1/2’
CENTER RAFTER LOUVER AGAINST CONSTRUCTION:
After making what number cut when initiating your bottom cut when Do you lover the section?
Fifth cut
Drop method:
While standing on ____, the first cut is made _____ to the lam-beam, stopping at the _____.
Purlins
Parallel
Purlins
Drop method:
Cut _____ and ______ to the purlins. Cut completely through plywood and _” x _” rafters. Cutters must work together. Cut _ to _ inches inside of the purlins to avoid hitting ____ ____.
Inside
Parallel 2x4’’
4-6’’
Metal hangers
Pull back method:
(Offensive)
Standing on _____, the first cut is made parallel to ___-____, stopping at purlins.
Purlins
Lam-beam
Pull back method:(offensive)
Cut small ______ through roof _____. Insert ____ _____into triangles. Rubbish hooks are used to pull back roofing and decking materials.
Triangles
Decking
Rubbish hooks
Pull back method:
(Offensiv)
Cut completely through the ____ rafter, and stop at the _____ rafter.
First
Second
Pull back method:(offensive)
Pullers pull back 4’ x 8’ panel with rubbish hooks. Panel will break at plywood _____.
Seam
Pull back method (offensive)
Pullers insert rubbish hooks over _____ rafter. Cutters cut completely through ___ rafters. Stop at ____ rafter.
Exposed rafter
Two rafters
Third rafter
Offensive louver:
While standing on _____, the first cut is made _____ to lam-beam, stopping at ____
Purlins
Parallel
Purlins
Offensive louver:
Cut parallel to _____; locate center rafter. ___ center rafter. Stop at ___ rafter. Cut _____ of third rafter. Cut ____ of third rafter. _____ section.
Purlins Roll Third Inside Outside Louver section
Louver off a lam-beam/ main beam (defensive):
While standing on a lam-beam, reach out approximately ___ feet, and make first cut _____ to rafters from ______ to _____.
3 1/2 feet
Parallel
Purlin to purlin
Louver off a lam-beam/ main beam (defensive):
Cut parallel to _____purlin, ___ center rafter, and stop at ___ ____.
Outside
Roll
Lam- beam
Louver off a lam-beam/ main beam (defensive):
Cut parallel to ____-____, from purlin to purlin.
Make _____ cut parallel to ____ purlin, roll center rafter, and stop at ____-___
Lam-beam
Fourth
Inside
Lam-beam
Louver off a lam-beam/ main beam (defensive):
Because of work area limitations (standing on a lam-beam), cutter and puller ______ _____. Before louvering section, make _____ cut. Cut from purlin to purlin.
Exchange tools
Outside
Louver off a purlin (defensive)
While standing on a purlin, start “___ ____.” Reach out as far as you comfortably can, approximately ___feet. Start at ____ lam-beam.
Skim cut
3 1/2
Outside
Louver off a purlin (defensive)
Skim cut” over rafters from ______to _____
Lam-beam to lam-beam
Louver off a purlin (defensive)
Cut parallel to ___ ____and stop at ____ Cut parallel to ____; locate center rafter. ____ center rafter and stop at ____ rafter.
Lam-beam Purlin Purlin Roll Third
Louver off a purlin (defensive)
Make _____ cut inside of ____ rafter. Make fifth cut _____ of third rafter After fifth cut, _____ section.
Fourth
Third
Outside
Louver
