Collapse 2nd Edition Flashcards
According to NFPA the leading causes of FF deaths are?
- Stress
- responding/returning from emergencies
- falls
- falling objects
- coming in contact w/ objects
- ff caught/trapped
- burning building collapse
4 factors that will increase burning building collapse?
- age of building
- abandonments
- lightweight construction
- faulty renovations
Buildings have a life expectancy of ?
75 - 100 yrs
older buildings structures of this country will collapse at an increasing rate and kill more ff unless there is a much greater effort in?
preservation, rehabilitation and legal renovation
Abandoned and neglected, unoccupied structures are know as?
Target hazards
* must be targeted by FD for frequent inspections, board-up orders and fire preplanning
What cracks masonry walls?
Freeze-thaw cycle
*wind and rain erode mortar between bricks.
* water seepage into an unheated building s masonry wall will freeze, expand, and crack the bricks
NFPA states unprotected lightweight steel bar joist fail when exposed to fire for?
5 to 10 min
What part of the WTC towers was the first part of the building to collapse according to NIST?
Floors
During a fire a braced-framed building will often collapse?
Inward/outward
A bend twist or curve of a structural element?
Deflection
A facade includes 4 collapse dangers?
Marquee, cornice, canopy, parapet wall
A combination of dead load a live load is?
Gravity load
a gravity-support beam designed to release itself from the masonry wall during collapse?
Fire cut beam
* a beam end that is simply resting on a corbel shel or a girder
The roof a church with a peak is supported by?
side walls
an unsupported lean-to floor collapse can be caused by
A bearing wall failure
Most structural elements are designed with a safety factor of?
2 or more
A bearing wall that supports floors and roofs of 2 buildings?
Party Wall
The danger of a truss only exist when?
under fire conditions
To melt steel what temperature is requried?
2400°
* really reached at a structure fire
2 of the most common structural elements formed by bending steel is?
C-Beam and bar joist truss
the failure temperature of steel is in the range of?
1000° to 1100°
What temperature does a structure fire typically reach?
1700°
Time Temperature curve test states that ?
1000° takes 5 min
1300° takes 10 min
1700° 1 hour
2000° 4 hour
2400° 8 hours
Steel fails at temperatures of 1100° and looses?
40% of its load carrying capacity
2 common types of roof decks used above the fluted-steel deck of a bar joist or c-beam which are?
lightweight insulation or precast concrete plank
what is the main concern of the fire service used to connect the truss members together?
Sheet Metal Surface Fasteners
*only connect the outer ½ in of wood truss members
In any structural element the critical aspect that are subject to failure during fire is ?
the point of connection
*are the first to fail
at a content fire like a mattress or couch the strategy should be?
stretch an interior hoseline and extinguish
If fire involves the structure and is burning through the concealed roof or floor space the strategy should be?
remove people
take exterior attack strategy
The most dangerous ceiling is ?
suspended ceiling
Degree of injury of a local collapse of plaster ceiling is determined by?
thickness of plaster
height of the ceiling from which it fell
cushioning system inside ff helmet
Most dangerous ceiling is?
suspended ceiling
What are the 3 common types of suspended ceilings?
wood grid
a metal grid system w/ removal panel
a metal grid system w/ permanently affixed ceiling
1st step for the rescue of firefighters trapped beneath a collapsed ceiling is?
sweep the collapse area above the ceiling w/ a hoseline and knock down flames.
One gallon of water weighs about?
8 lbs
If working beneath a suspended ceiling that has partially collapse or is sagging badly, what should ff do?
Shore up the weakened ceiling temporarily with a Portable Ladder
When a suspended ceiling collapses, the grid system must first be?
Cut apart with a power saw
What can ff use to tunnel beneath collapsed ceiling or as a raising lever?
Portable Ladder
most often constructed of wood and found in private homes which type of stairs?
L-Stair
*2 sections stair change direction at a 90-degree angle
in the wooden interior of the building and logically the best avenue for initial fire attack is?
the stairway
Stairs found in masonry enclosures are independent of the floor structure and will not collapse during floor failure?
U-Return Stairs
The most serious collapse injuries on u-return stairs is?
collapse of intermediate landing collapse.
*ff stepping on them
the steel u-return stairs that sustain the most intermediate landing collapse are?
treads and landings constructed of stone unsupported by a steel pan
The most frequent collapse collapse of a u-return stair is?
stone stair tread or step
Intermediate landings made of stone or marble on steel-framed u-return stairs most often collapse under?
weight of ff descending the stairs
3 general classifications of fire escapes?
Party Balcony
Exterior screened
Standard fire escape w/ mechanical street ladders
Safest fire escape is ?
Exterior Screened fire escape
At fire escapes ff are injured by?
Step collapse
*weakened by corrosion
To avoid fire escape collapse, ff should climb steps?
smoothly and not stamp down on the tread, grip railing
* place one foot and apply pressure to the step first before placing full weight
What are new party balcony constructed of?
wood or concrete
Most common type of fire escape found on residential buildings is?
Standard fire escape
Standard Fire escape
60°- 70° angle of ladder (Steeper)
*see a kid or elderly bring in through window of safe apartment and through interior stairwell
Sliding drop ladder is held in place on the lowest balcony of a standard fire escape by?
Pendulum hook
FF lowering a drop ladder should stand?
Beneath the fire escape
*if it falls out of its tracks it will fall out away from fire escape
*a safer alternative is a ground ladder
When placing a boot on a fire escape, it should be placed?
near outside of the step where it meets the stringer
When descending down a weakened standard fire escape ladder you should?
face the ladder and hold on to guide rails
3 ways a wood-frame structure may collapse?
90° angle
inward/outward (3 story braced frame frequently collapse)
Lean Over and collapse on it’s side
Often signaled by the corners of the falling wall splitting apart from the remaining walls?
90-degree-angle wall collapse
Most dangerous, sudden, gives no visible warning signs prior to failure, may involve the collapse of 2, 3, 4 walls simultaneously?
inward/outward
*most common in braced frame
During a fire in a structure with masonry walls, it is rare that more than one wall will collapse at one time except in?
an explosion
Of the 3 major types of wood-frame construction, this one presents the greatest ff danger?
Braced-frame
Today, is the most widely used method of wood-frame construction?
Platform Construction
* superior to balloon and brace-framed because of no concealed wall voids that extent more than 1 floor
Lightweight wood truss construction suffer?
floor and roof collapse
* not wall or global (total) collapse of the entire structure.
*danger is early floor and roof collapse of truss floors and roof
3 factors that contribute to inward/outward collapse?
- Fire destruction of bearing wall
- failure at mortise and tenon connections
- exterior wall overload
In older buildings bearing walls were on?
The side
Private new homes have bearing walls on?
Front and rear
Kills more firefighters than fires in any other occupancy ?
Unfinished buildings
Major life hazard during a daytime fire at a building under construction will be?
Workers trapped on upper floors and especially workers inside cab of a crane
Crane collapse most often when ?
Overloaded, moved, assembled, or disassemble
*not during fire
The relative moisture content of concrete is greatest during?
The 1st 27 days after pouring
2 types of concrete spalling
Explosive spalling and dropping spalling
Are required to be noncombustible and at least 30 feet from building from buildings under construction?
Shanties
Number 1 ignition source found inside workmens shanty?
Portable heating device
In any building under construction, most state laws require?
Standpipe system in operating condition that rises 7 stories or 75 feet
Some state laws when a high-rise building under construction exceed 150 ft or 15 stories that ____ be placed to?
Os&y contol valve to subdivide the vertical pipe riser into sections
Construction sheds, shanties will be closed on weekends and should be examined?
During working hours
Collapse large caliber stream capable of delivering more than ___ gpm?
300 gpm
Roofs surrounded by parapet walls on the four sides of the building are?
Prone to water buildup
Sounds of large caliber streams
Stricking brick wall
Stikes side of wooden building when it enters a window
Stricking brick wall - splatter
Stikes side of woodwn building - drum
Enters a window - distant rumbling
One of the most important objectives of collapse rescue operations is?
Control and organization
After establishing command at a building collapse, one of thw 1st actions the IC must direct is to?
Restrict access to the scene
Terrorists attack IC should divide operations into ?
2 branches
- one for firefighting
- collapse sear-and-rescue
Search and rescue plan used in oklahoma and New York?
- Secure the area
- Survey collapse site
- Shut off utilities
- Remove surface victims
- Search voids and remove trapped victims
- Take time out
- Tunnel/trench
- Begin gwnwral rubble removal
After ordering police to secure the area at a collapse, the IC must order?
Site safety survey of the 6 sides (4 sides above and below)
At a collapse during time out who shoukd bw in the conference?
IC
Operations officer
Planning officer
Victim tracking officer
Whwnevwr there is a danger reported to thw command post who should this information be relayed to?
RIT
The most dangerous type of parapet wall is ?
Ornamental cast stone
Parapet wall most susceptible to total collapse are oftwn attached to steel reinforcement rods and angle rods?
Ornamental cast stone and decorative terra-cotta parapet walls
Complete withdrawal of firefighters
Any fire where steel bar joist, timber or lightweight truss construction is exposed
*large body of fire on several floors in an old building
At what temperature does steel warp, sag, bend and collapse when heated?
1100 to 1200
The best fire-resistive building in America?
Concrete structure
Structure that limit and confine fires best and suffer fewest collapse are?
Reinforced concrete
What is the safety factor?
2 to 1
*its exactly what you get, no extra
Most fire safe building in america?
Empire state building
After they found out Asbestos was hazardous what was used as a spray-on coating for steel?
Vermiculite or volcanic rock ash substance
Strategy is uded in a high-rise building where time necessary for total evacuation would be impractical is?
Defend-in-place
The distance defined as remote is?
15 feet
Phases of elevators?
Phase I - recapture elevator
Phase II - firefighter use
Phase III - enclosed and protected from smoke, fire and hose stream and sprinkler water
Occurs whwn an initial load failure spreads from the structural element to structural element, resulting in collapse of an entire structure?
Progressive collapse
High-rise fire -resistive steel frames are only protected against heat for ?
A maximum of 4 hours
One of the most important size up duties of 1st in chiefs and company officers is?
Locating fire and determining severity of it
A post-fire analysis is a strategy, tactics, and safety investigation from the point of view?
Fireground commander
There are many benefits in conducting a post-fire analysis. The greatest benefit occurs to whom?
Chief officer doing the analysis
What are the 3 parts of post fire analysis?
Part I - Printed form or fact sheet that is filled out and includes questions about the fire
Part II - fire ground diagram
Part III - photographic documentation
Types of buildings and fire spread weakness as well as general collapse characteristics:
Type I - fire-resistive:
- fire spread weakness :A/C
- collapse characteristics: localized collapse by spalling chunks of concrete
Type II - noncombustible:
- fire spread weakness: combustible roof deck
- collapse characteristics: early roof collapse
Type III - ordinary Construction:
- fire spread weakness: voids -
- collapse characteristics: parapet walls often collapse near roof level
Type IV - Heavy Timber:
- fire spread weakness: Fire load/radiant heat
- collapse characteristics: floor collapse followed my masonry wall collapse
Type V - wood-frame
- fire spread weakness: exterior walls
- collapse characteristics: Bearing Wall collapse
3rd and most important part of post-fire analysis is?
Photographic documentation
The collapse danger of a cellar is?
The 1st floor
