Chapter 16: Building Materials, Structural Collapse, and Effects of Fire Suppression
Traditionally, how large is the collapse zone?
1 1/2 times the height of the structure
What is a concern about lath and plaster during fire?
Conceals hidden fires and adds fuel to the fire
How do a building's contents affect fire growth and structural collapse?
Contents can retain water and increase the stress on structural members
In which stage of fire development does structural collapse become likely due to the weakened state of structural members and buildup of water?
Decay
Which type of building material is used to protect other materials because its moisture content gives it excellent heat resistance?
Gypsum wallboard
Which statement describes how glass will react under fire conditions?
Heated glass may crack when water is applied
How does the size of a wood structural member affect how it reacts to fire?
Heavy timbers remain strong even after exposure to direct flame
How does reinforced concrete react to exposure to fire?
It performs well, but can lose strength through spalling
How can HVAC systems affect tactical ventilation?
Move products of combustion to unaffected areas
Which type of building material can produce toxic gases and rapidly deteriorate under fire conditions?
Oriented Strand Board (OSB)
Which building material can potentially be harmful to firefighters because it contains a glue called urea formaldehyde that gives off a hazardous gas when it is heated?
Particle board
Which factor is likely to affect the speed with which a steel structural member falls under fire conditions?
Size
How does heat affect masonry?
Stones and concrete may experience spalling when they are heated
Which statement accurately describes how building materials and configuration affect fire behavior in a structure?
The longer the fire has burned, the most likely it is that structural integrity has been compromised
Which type of collapse is common for a Type V construction building?
Walls collapsing inward
How can water from fire suppression affect a building's structural stability?
Water weight added from suppression can cause floors to collapse
Which type of building material is affected by size and moisture content during fire conditions?
Wood
When establishing collapse zones
apparatus must not be positioned in the collapse zone
What is an indicator of structural collapse?
distorted structural members
When should firefighters begin considering the potential that a building will collapse?
during preincident surveys and size-up
When heated, steel structural members tend to
elongate and push walls outward
Overhaul operations may affect a structure's stability when
firefighters accidently cut through load bearing components
When should a collapse zone be established at a structure fire?
once defensive strategy is adopted
What should take place immediately after the collapse zone is cleared?
personnel accountability report
Cast iron may crack or shatter when it is
rapidly cooled with water
Why are buildings under construction more susceptible to fire spread?
sprinklers and FDCs are not yet operational
Once it is determined that collapse is imminent
the collapse zone should be cleared as soon as possible
Why can abandoned buildings pose great danger of fire and collapse?
the interior may be gutted and altered
Little or no water runoff from the interior of the structure can be an indicator that
the structure is retaining water and is at risk of collapse