Chap 1 General Collapse Info Flashcards
Unprotected lightweight steel bar joist fail
When exposed to 5-10 min of fire
Four factors that will increase building collapses are
- The age of the building ( buildings have a life span of 75-100 years)
- Abandonment - buildings deteriorate due to exposure to weather conditions
- Use of light weight construction materials
- Faulty renovations -illegal and improper building construction and renovations
Fire resistance and collapse resistance are directly related to
The Mass of a building
Lightweight building construction includes small unseen changes
Elimination of wood bracing between flor and roof beams
Wood stud wall and floor construction spaced 36 inches instead of 16 inches
The use of 1/4 inch thick wood sheathing for roofs and floors instead of 3/4 or 1”
Roofs supported by 2x4 “ wood beams instead of 2x8 or 2x10 “ beams
Structural collapse is
Any portion of the structure that falls as a result of fire
No matter how small
Example glass that falls do to heat to window frame ( not when fireman vents )
Fallen object is
Any object other than the structure that falls is thrown or knocked loose from burning building
Glass falling because of venting by ff
What is the most common falling object from at a structural fire
Broken glass from windows being vented
When objects must be thrown out of windows during overhaul or salvage then :
- Obtain permission from IC
- Notify or assign a ff outside the building to clear the area of civilians and act as a guard
- After the area is clear the ff acting as guard signals when to throw the smoldering objects out or break off jagged glass shards
- When all objects have been thrown out the window notify ff who has been assigned as safety guard
Which part of the building is more likely to collapse and kill ff?
Floors collapse the most ff
Roof is next most dangerous
Then wall
then ceiling collapse
