Burning building collapse is the ____ leading cause of death?
Fourth
The NFPA states that stress is the number ____ leading cause of death?
One (42%)
Falls, falling objects, and contact with objects is number ________ leading cause of death?
Two (27%)
Exposure to fire products is the ____ leading cause of death?
Third (18%)
Burning collapse is the ____ leading cause of death?
Fourth (7.4%)
Four factors that contribute to building collapse?
AALF
1. Age
2. Abandonment
3. Lightweight Construction
4. Faulty Renovations
The term "Structural Collapse" according to Dunn is defined as?
Any portion of a structure that fails as a result of fire
T or F
If a burned section of plaster ceiling falls on top of a firefighter, it is structural collapse?
TRUE
Arch:
A curved masonry structure used as a support over an open space. (pg10)
Balloon Construction:
Studs that extend from foundation to the top plate near the attic
A beam is a horizontal structural member subject to compression, tension, and shear, support by one of 3 methods:
Cantilever beams, continuous beam support (3 point connection), simple supported beam (2 point connection)
Cantilever Beam:
a beam supported or anchored at only one end, which is considered a collapse hazard during fire exposure.
A beam supported at both ends?
Continuous Beam Support
a beam supported at both ends?
Simple Supported Beam
Braced Frame Construction:
sometimes called "post and girt" construction; Vertical timbers called post reinforce each of the four corners of the structure, and the horizontal timbers called girts reinforce the floor level. Posts and girts are connected by fastenings called mortise and tenon joints. During a fire, braced frame building wall often fails in an inward/outward collapse.
Buttress: (inside version is called a pilaster)
A wall reinforcement of brace built of the outside of the structure, sometimes called a wall column
Collapse:
A failure of any portion of a structure during a fire.
Curtain-Fall Wall Collapse:
When an exterior masonry walls drops like a falling curtain cut loose at the top.
Inward/Outward Collapse:
The collapse of an exterior wall that breaks apart horizontally
Lean-Over collapse:
A type of wood framed building collapse indicated by a burning structure slowly starting to tilt or lean over to one side
Lean-to-Floor Collapse:
A floor collapse in which one end of the floor beams remains partially supported by the bearing wall, and the other end of the floor beam collapses on the floor below or collapses but remains supported
90 Degree Angle Wall Collapse:
A type of burning building collapse. The walls falls straight out as a monolithic piece at a 90 degree angle, similar to a falling tree
Pancake Floor Collapse:
The collapse of one floor section down upon the floor below in a flat, pancake-like configuration
Tent Floor Collapse:
A floor collapses in the shape of a tent
V-Shape Collapse:
The collapse of a floor at the center of the floor beams.
Column:
A vertical structural member subject to compressive forces
Columns and bearing walls are parts of?
Vertical frameworks
Girders and beams are parts of?
Horizontal frameworks
Other primary structural members are?
Ridgepoles, hip rafters, headers, and trimmer floor beams
Convenience Stair:
An opening in a floor slab for a stair between floors, Sometimes called access stair
Coping Stone:
The top masonry tile or stone of a parapet wall,designed to carry off rain water
Corbel:
A bracket or extension of masonry that projects from a masonry wall.
Corner Safe Areas:
Four flanking zones around a burning building.
Deck:
a horizontal surface covering supported by a floor or a roof beam.
Deflection:
A bend, twist, or curve of a structural element under a load.
Facade:
The front or face of a building.
Fire Cut Beam:
A gravity-support beam end designed to release itself from the masonry wall during a collapse
Fire Load:
The measure of maximum heat release when all combustible material in a given fire area is burned.
Fire Resistance Rating:
A relative rating to indicate in hours how a long a wall, floor, ceiling, beam, or column will sustain performance during a fire.
Fluted Metal Deck:
A wavy pice of sheet steel deck used to support concrete floor.
Force:
The cause of motion, change in motion, or stoppage of motion.
Frame Tube Construction:
The world trade center towers were frame tube construction
Girder:
A structural element that supports a floor or roof beam.
Global Collapse:
A total collapse of the building.
Gravity Load:
A combination of dead load and live load.
Gusset Plate:
A metal fastener in the form of a flat plate used to connect structural members.
Hat Truss:
A means of load distribution connecting core columns and perimeter columns.
Header Beam:
A support used to reinforce an opening in the floor of a wood-framed ordinary, or heavy timber building.
Joist:
A piece of lumber used as a floor or roof beam
Interstitial Space:
A concealed space between floors used to contain large mechanical and electrical equipment.
Kip:
one kip equals 1,000 lbs
Laminated Beam:
A glued or layered composition beam
Lintel:
A horizontal piece of timber, stone, or steel placed over an opening in a wall
Loads:
Forces acting upon a structure.
Axial Load:
Passes through the center of a structure and is the most efficient manner by which a load can be transmitted through a structure.
Concentrated Load:
A load applied at one point or within a limited area of the structure.
Dead Load:
A static or fixed load created by the structure itself and all permanent equipment within.
Eccentric Load:
A load transmitted off-center or unevenly through a structural member.
Impact Load:
load applied to a structure suddenly, such a a shock wave.
Lateral Load:
Any type of loa applied to an upright structure from a direction parallel to the ground.
Live Load:
A transient or movable load
Static Load:
A load that remains constant, applied slowly.
Torsional Load:
A load creates twisting stress on a structural member.
Wind Load:
A lateral load imposed on a structure by wind.
Load Stress:
An internal stress created by a load in a structural element, including compression stress, tension stress, and shear stress.
Mortise:
A structural connection often used in braced wood frame construction.
Multilevel Floor Collapse:
a floor failure that causes one or more floors below and one or more enclosing walls to collapse.
Open Web Steel Bar Joists:
a lightweight steel truss used as a floor or roof beam.
Passive Fire Protection:
the fire containment provided by a structure is considered "passive" fire resistance.
Pilaster:
a masonry column bonded to and built as an integral part of the inside of a masonry wall.
Platform Wood Frame Construction:
A building of this construction has one complete level of 2x4" wood enclosing walls raised and nailed together; floor beams and deck for the next level are constructed on top of these walls.
Primary Structural Member:
a structure that supports another structural member in the same building.
Progressive Collapse:
when the initial structural failure spreads from structural element to structural element resulting in the collapse of an entire structure.
Purlin:
a timber laid horizontally perpendicular to support the common rafters of a roof.
Restrained Beam End:
a welded, nailed, bolted, or cemented end of a floor or roof beam.
Ridgepole:
a horizontal timber that frames the highest point of a peak roof
Safety Factor:
The quotient of the load that will cause a structure to collapse divided by the load of a structure is designed to support.
Stress:
a force extended upon a structural member that strains of deforms its shape.
Tenon:
a projecting, reduced portion of a timber designed to be inserted into the mortise hole of another timber.
Terrazzo:
a polished floor covering made of small marble chips set in several inches of cement.
Timber:
Wood larger than 2x4"
Trimmer Beam:
a wood beam constructed around the perimeter of a floor opening.
Truss:
a braced arrangement of steel or wood-frame work made with triangular connecting members.
Unrestrained Beam End:
a beam resting on a support, held in place only by gravity
Area Wall:
a freestanding masonry wall surrounding or partly surrounding an area.
Bearing Wall:
an interior or exterior wall that supports a load in addition to its own weight.
Demising Wall:
a partition wall that extends from floor slab to floor slab above.
Fire Wall:
a nonbearing, self-supporting wall designed to prevent the passage of fire from one side to another
Freestanding Wall:
a wall exposed to the elements on both sides and the top, such as a parapet wall
Parapet Wall:
the continuation of a party wall, an exterior wall, or a firewall above the roofline
Party Wall:
a bearing wall that supports floors and roofs of two buildings
Spandrel Wall:
The portion of an exterior wall between the top of one window opening and the bottom of another.
Veneer Wall:
a finished or facing brick or stone wall used on outside of a building.
Horizontal Collapse Zone:
the horizontal measurement of the wall
Vertical Collapse Zone:
The expected ground area that a falling wall will cover when it collapses.
How does smoke spread in a high-rise building?
HVAC system
NFPA recommends that a roof of noncombustible/limited combustible structure be built as?
The total weight of asphalt and insulation not weigh more than 12-15 lbs per square feet or roof
Type 2 Const. may allow fire to spread through?
The combustible roof deck
Type 1 fire-resistive const. may allow fire to spread by?
Auto exposure from window to window
Whats a major problem in an ordinary constructed building?
The fire and smoke spread throughout concealed spaces.
What's the largest and most serious concealed space?
Common roof space or cockloft
For a building to qualify as heavy timber const. a wood column cannot be less than?
8 in. thick in any dimension and wood girder cannot be less than 6 in thick
Type 4 creates radiated heat that can travel?
up to 80 ft and ignite combustible portions of nearby buildings.
True/False; wood-frame const. is the only one of the 5 types that has combustible exterior walls?
True
How many sides do wood-frame building have?
7, the exterior walls
Concrete ceiling collapse in a reinforced concrete fire resistive building is caused by?
Spalling
What is the main disadvantage of the open web bar joist?
Its susceptibility to damage by fire in the combustible contents inside the building.
Ordinary Construction building main hazard?
Parapet Walls
3 ways in which a masonry wall may collapse?
1. 90-degree angle
2. Curtain fall
3. Inward/Outward
Which collapse is the most common?
90-degree angle collapse
Collapse zone distance?
Equal to the height of the wall
What position should firefighters be in to protect against collapse?
Flanking
What's the most dangerous parapet?
One constructed as the front wall of a one-story structure above several large display windows.
Leading cause of death by collapse?
Floor failure.
3 ways floors collapse
1. Floor deck may collapse
2. Floor beam collapse
3. A multilevel floor collapse
Cause of a lean-to-floor collapse
Floor pulling away from a bearing wall
Cause of a unsupported lean-to floor collapse
A bearing wall failure
Cause of a tent floor collapse
By an explosion
Cause for a V-shape collapse
Center floor overload
Cause for pancake floor collapse
Impact of a heavy falling object
Strategies and Tactics for floor deck collapse?
Sound the floor
Strategy and tactics for floor beam collapse
use the reach of the hose stream
Strategy and tactics for multilevel floor collapse
Withdraw firefighters
The 3 recurring factors that contribute to floor collapse in burning buildings?
1. Vacant buildings
2. Renovated buildings
3. Buildings overloaded
Types of peaked roofs
Gabel
Hip >3 main
Gambrel
Shed
Manshard
Primary structural members in sloping roof const.
Ridge rafters
Hip rafters
Bearing walls
3 most common types of wood const. used for sloping roofs?
1. Timber truss
2. Plank and beam
3. Rafter const.
Two ways for FFs to protect themselves on a peaked roof?
1. A roof ladder hooked on the ridge rafter
2. Operate off of a aerial
T/F Truss const. is the most dangerous roof system that a FF will encounter?
TRUE
How do you quickly determine if a fire has spread to the roof space of a bowstring truss?
A triangular cut may be made in the sloping front or rear of the roof from the safety of an aerial apparatus.
When a truss roof appears weakened by fire, where should FFs retreat?
a direction perpendicular to the roof trusses
The most unstable structure in a community?
Places of worship
Strategy for a place of worship?
Always prepare for defensive master stream
What is the primary ventilation hole in a place of worship?
A rose window (stained glass)
What's the most unstable feature of a place of worship?
The temple tower or steeple
When a fire building has a steel bar joist system supporting the roof, what kind of ventilation is preferred?
Horizontal
The 2 most common structural elements formed by bending steel?
1. Bar joist truss
2. C-Beam
The failure temperature of steel?
1,000-1,100 degrees
The least effective way of protecting steel?
Spray-on fire-retarding material
Four factors that determine the speed with which unprotected steel will fail during a fire?
1. Temperature of fire
2. The load stress
3. The steel thickness
4. The fire size
Unprotected steel bar joist trusses and steel c-beams can collapse in how many minutes?
5-10
2 types of wood truss systems?
1. Heavy timber
2. Lightweight wood
Lightweight trussed rafters are expected to collapse in how many minutes?
10
When fire enters the concealed spaces there is how much % faster fire spread?
100%
Where are voids that allow firefighters to escape at during ceiling collapse?
Near enters and shelves
Types of ceilings?
1. Directly affixed to the floor or roof joists above
2. Suspended below the joists
The most dangerous ceiling?
Suspended
Types of stairs?
1. Straight run
2. U-turn
3. L-shaped
The safest type of fire escape?
Exterior screened in balcony
Hazard for party balcony?
Can get overloaded and fail
The most common fire escape?
The standard fire escape
T/F victims should be considered a life hazard on a fire escape?
True, and should be assisted down to the floor below the fire into a window and use the interior stairs
She should a firefighter stand when lowering a drop ladder?
Under the escape to avoid being hit by it or use a ground ladder
The most common danger when climbing a fire escape?
Step collapse
Three ways the wood-frame building can collapse?
1. 90 degree angle collapse
2. Entire building can lean over and collapse on its side
3. One or all four walls may fall in an inward/outward collapse
Which wood-frame construction present the greatest hazard?
Brace-frame
Four most widely used wood frame construction?
1. Braced-frame
2. Balloon frame
3. Platform frame
4. Lightweight wood frame
T/F special occupancy structures kill more firefighters than any other occupancy?
True
Buildings under construction or demolition are classified as what?
Special occupancy
What should be used to protect a crane operator at a fire in a building under construction?
A master stream
A structure that is 75-100 years old is what?
At the end of its life span
Target hazards are?
Dangerous and abandoned, neglected, unoccupied structures
Target Hazards need?
Frequent inspections, board up orders, and pre
fire planning
per NFPA unprotected lightweight steel bar joists fail when exposed to how many minutes of fire?
5-10 minutes
How thick is glass in a residential building?
and in a commercial?
1/16" or 1/8"
1/4" or 1/2" and weigh 2.5-5 lbs. per sq. ft.
FFs inside a burned out structure during overhaul/salvage should never throw out smoldering material or trim glass shards by knocking them outside unless?
The area below has been cleared and a FF is standing guard outside at ground level
Procedures for throwing objects out of a window during overhaul?
1. Obtain permission from I.C.
2. Notify or assign a FF outside the building to clear the area or civilians and act as a safety guard
3. After the area is clear, the FF actin as guard signals when to throw the smoldering objects out or breaks of jagged glass shards
4. When objects have been discarded out the window, notify the FF below who has been assigned safety guard
Post fire analysis
-Fact sheet recording building information
-Fireground diagram should be drawn up showing the area of collapse.
-Photographic color slide documentary of the area should be prepared
What should a Post Fire Analysis be used for?
FF training on strategy and tactics
5 types of building construction?
1. Fire Resistive
2. Noncombustible/ limited combustible
3. Ordinary brick-and-joist
4. Heavy timber
5. Wood frame
How can fire spread in a fire resistive building?
By a network of holes, concealed spaces, and voids
When a fire in a noncombustible building is darkened down, the I.C. should have a FF do what?
Check the covering above the fluted deck for extension
The heat from a fire reaching the underside of a corrugated steel deck is transmitted upward to the concrete floor above, the concrete floor may buckle upward how many inches?
Between 6-12 inches.
If it s absolutely necessary to operate a master stream in a collapse zone, what should be done?
It should be secured to direct the stream effectively and safely and then left unattended.
During a firefighting operation, a parapet, marquee, canopy, or cornice should be what?
Monitored for failure.
What is more of a collapse danger, a canopy of marquee?
Canopy.
If a bolt, cable or framework connector of this non-continuous beam fails on a canopy, it can cause what?
A complete canopy collapse.
What is the most dangerous canopy?
A metal or wood shed suspended over a truck loading area.
When the collapse zone is greater than the reach of the hose stream, the I.C. should consider what?
Operating the hose stream from a flanking position.
Because of falling objects the most dangerous area outside a burning building is?
The sidewalk directly in front.
Ornamental cast stone and decorative terra-cotta parapet walls are often attached to steel reinforcement rods and angle irons, making them susceptible to what?
Total collapse.
If a bowstring truss roof fails it will shift the weight to the parapet wall and cause?
A violent inward/outward collapse.
When do parapet walls often collapse?
During the overhaul stage.
Structural Hierarchy:
The destructiveness of a collapse depends on the first structure to fail, and where this structure is positioned within he building supporting system.
Multilevel floor collapse most often happens in burning buildings with?
That have columns and girders supporting the floors.
What should there be during an uncontrolled fire in a High-Rise fire?
A "time-limit" for interior
operations
What was a new benchmark in the fire service?
The evacuation of FFs from a burning high-rise building due to structural danger (Philadelphia Fire Chief "Meridan Fire")
Priorities of firefighting
1. Life Safety
2. Incident Stabilization
3. Property Protection
What should be done if a fire rages out of control for hours despite FF's efforts?
A structural engineer should be called to evaluate the buildings stability.
If FFs are withdrawn from a high-rise fire, what should still be done?
Continue to supply the sprinkler system and use master streams from adjoining high-rise buildings.
What is a Fire Breeder?
A building where arsonists can start a fire and remain hidden from view.
When is the most dangerous time for floor collapse?
During the end of the fire, the decay stage, after the fire has been extinguished.
What should be done after a major fire where master streams have been used?
The building should be inspected before overhauling begins.
If a building is in danger of collapse and overhauling cannot be done, what should the I.C order?
Outside master streams to cool down the smoldering fire - called "Hydraulic Overhauling" or "Defensive Overhauling"
What are the primary structural members in wood construction?
Header and trimmer beams
What will the collapse of a primary structural element cause?
The collapse of other structural supports
Which roof has the largest area of unsupported roof deck?
Truss roof
Where is roof rotting often found?
At roof edges, where roofs change slope and where sloping roof abuts a vertical plane. FFs should avoid walking on these areas whenever possible.
Roof coverings can be divided into 2 categories?
Built-up coverings and prepared roof coverings
WHAT DO BUILT-UP ROOF COVERINGS CONSIST OF?
Several layers of materials applied to the roof.
What do prepared roof coverings have?
Materials nailed to a roof deck
One slate or tile shingle can be how thick, and weigh how many lbs.?
2 inches thick and weigh up to 10 lbs.
Several causes of slate and tile shingle collapse?
-The wooden roof deck to which the shingles are nailed to is destroyed by fire
-All stone is adversely affected by a sudden changes in temperature, it cracks and breaks when suddenly heated by flame
-A powerful hose stream striking a sloping roof can drive slate or tile from the roof top into the air, causing broken pieces to fall around the perimeter of a burning building where FFs are working
What is another danger of slate or tile roofs?
That they conceal a fire weakened roof structure.
A high-pitched roof, like that of an "a" frame or English Tudor roof, cannot be walked on safely even with the assistance of a roof ladder. What should a FF do?
A FF must operate from an extended aerial ladder or while standing in the bucket of a tower ladder.
What determines if a FF can walk safely on a sloping roof?
Pitch
What will a roof ladder NOT protect FFs from?
A roof rafter collapse
What will a roof ladder protect a FF from?
a roof deck collapse
When FFs are operating at a private home with a sloping roof, what is more effective than cutting a vent hole?
Venting top-floor windows
The type of roof construction should be included in what?
The pre-fire plan
All depts. should develop a SOP for sloping roofs based upon?
Life safety, fire containment, and property protection
3 ways FFs die when operating at fires involving timber truss construction?
1. FFs can be killed operating outside, when the truss collapse, they can push out a masonry wall, the falling roof can cause a secondary collapse
2. FFs operating on the roof can fall through the collapsing roof.
3.FFs operating inside can be crushed and burned to death when the collapsing truss roof falls on them.
Timber:
Wooden construction larger than a 2x4 but not large enough to be classified as heavy timber
A timber roof can be built in a variety of shapes...
Incline plane
Parallel Chord (flat roof)
Bowstring (most common)
When a FF discovers the type of truss in a building fire should immediately do what?
Relay this info to the officer in charge
The large space created by the concave , arched underside of the bowstring truss roof acts as what?
A heat sink
In a timber truss building the main fire will be where?
In the
roof structure, not in the content below
What should be done if a fire extends into a timber truss attic space?
Prepare for a defensive outside attack and protect exposures
The fire strategy for the first arriving engine co. at a timber truss roof building without a ceiling should be?
To attack the fire directly with a large diameter hose.
What is the key to safety when operating at a fire in a truss construction building?
Communication
Where should ventilation take place at a place of worship?
The rose window first, then the side windows nearest the fire.
If a fire reaches the attic of a place of worship...
It cannot be extinguished with handheld lines.
How many minutes can lightweight construction last with fire exposure?
5-10 mins.
What is the most common flat roof supporting member used in older ordinary constructed buildings?
Conventional solid wooden joist
Steel failure depends on?
The load it carries , the dimensions of the steel beam, and the protection insulating covering over the steel surface.
3 most common methods to protect steel from heat
1. Concrete encasement
2. Membrane ceiling (fire retarding ceiling0
3. Spray-on fire retarding material (most popular) also is the least effective method for protection
The lightweight steel bar joist must be viewed by FFs as extremely hazardous in roof and floor construction for 2 reasons?
1. Failure characteristics of unprotected steel
2. Joist spacing
Strategy for lightweight wood truss roof or floors?
Content Fire- stretch a hose line
Structure Fire- burning in a concealed space or floor spaces, go defensive
Suspended ceilings are most often found in 3 occupancies?
1. Stores
2. Top floors of multiple dwellings
3. Renovated buildings
Which part of the suspended ceiling traps or pins FFs in a burning building?
The grid system or framework behind the ceiling sheathing
What is the heaviest part of a suspended ceiling?
The grid system
The most important first step for the rescue of FFs trapped beneath a collapsed suspended ceiling is to?
Sweep the collapse area above the ceiling with a hose line and knock down the flames.
Straight run and L-shaped stairs are built through floor openings in the center or the side of a structure and are dependent upon what?
The stability of the floor for support, it will collapse with the floor.
If a stairs appears in danger of collapse, what should FFs do?
Place a ladder over the weakened stair rise and climb unto the ladder rungs
What it the most common fire escape?
The standard fire escape
Should FFs stand beneath a counter-balance stairway or it's cable, pulley wheel, or heavy balancing wheel?
NO
Why is the inward/outward collapse the most dangerous?
Because it is sudden, it gives no visible warning signs prior to failure, and unlike most other building failures it may involve the collapse of 2, 3, or 4 walls simultaneously
3 factors that contribute to inward/outward collapse of a breached frame wooden building?
1. Fire destruction of bearing walls
2. Failure at the mortise-and-tenon connection
3. Exterior wall overload
If a building under construction is exposing a crane, what should the I.C. do?
Setup a collapse zone equal to the height of the crane.
2 types of concrete spalling?
1. Explosive
2. Dropping
What is the most serious type of fire at a construction site?
The combustible formwork used to support a cast-in-place concrete floor
What are shanties required to be?
Noncombustible construction and at least 30' from the building under construction
What is the strategy for fires in formwork supporting floors?
Outside aerial master streams
Which hoist car do you use in a construction site?
The one for personnel not material
What are hazards with the Bell System (hoist car)?
1. Has no safety brake
2. The bell signal sounds like a SCBA alarm
When is the best time to do a pre-fire inspection on a building under construction?
On the weekend
When should construction sheds, shanties, and offices be inspected?
During work hours?
What is the first order an I.C. issues at a collapse?
To secure the area
The collapse rescue plan of action:
1.Secure the area
2. survey the entire site
3. Shut-off utilities
4. Rescue surface victims
5. Search voids
6. Take a safety time out
7. Tunnel and trench to buried victims
8. Start general rubble removal with cranes.
A list of safety actions an I.C. may consider when receiving a reported danger
1. Acknowledge the report and take no immediate action
2. Light up the danger area
3. Assign an experienced officer or chief to investigate
4. Increase supervision
5. Alert a R.I.T. response
6. Evaluate an unstable structure with a telescope lens
7. Rope or tape off danger area
8. Establish a collapse zone around a danger area
9. Evaluate people and FFs near a reported danger area
10. Order a ;atrial withdrawal of FFs from a section of building
11. Change strategy from offensive to defensive by withdrawing FFs
12. Order immediate emergency evacuation of all FFs.