Chp. 4 Building Systems Flashcards
What roles do stairs provide in a building system?
- enable access to multiple levels of a structure
- serve as a basic component of building egress during
an emergency.
Convenience stairs
- not part of the means of egress
- usually open and connect only two levels per code
limitations.
Six common types of stairs:
- straight run
- return
- scissor
- circular
- folding
- spiral
Buildings that often include scissor stairs:
- airport terminals
- convention centers
- malls
- cinema complexes
The modern design arrangement for scissor stairs allows for ______________ at each floor landing, which provides additional exit capacity. Older designs restrict egress from the stairway into one corridor on even numbered floors and into opposite corridors on odd numbered floors.
- ingress and egress
Circular stairs serve only ________. The minimum width of the run is usually _______.
- two levels
- 10 inches
Firefighters should be aware that springs in ___________ lose tension rapidly when exposed to heat, and the stair assembly may swing down into the structure during a fire, providing a vertical path for fire and smoke spread.
folding stairs
Both folding stairs and fixed ladders may have _________ lower than the weight of a firefighter wearing full PPE. Many departments recommend against using these stairs for firefighting purposes.
weight limitations
Measures indicated in building codes to protect stair enclosures include:
- limited penetrations for light, fire protection, and
environmental control - required self or automatic closing fire rated doors
- separation from rest of building
- stairway vestibules
Building codes have traditionally required a minimum of one smoke proof stair enclosure for stairs serving buildings ____________. More recently, codes also require protection for stairs serving floor levels more than ________ the level of exit discharge.
- five stories or higher
- 30 feet below
Typically located on the exterior perimeter of the building and are entered through ventilated vestibules or open exterior balconies .
smoke proof stair enclosures
A correctly operating system should allow firefighters to begin suppression operations concurrently with occupant egress. In high rise structures, codes require dedicated, ________________ designed solely to provide firefighters a safe route to access and attack a fire.
pressurized stairways
Protect the stairway enclosure and provide a means of smoke ventilation before smoke enters the stair enclosure. Accessed through a vestibule or an exterior balcony.
passive smoke proof enclosures
Building codes typically allow the use of open stairs in buildings only when they connect no more than __________ above the basement level.
two adjacent floors
Conveyor systems often penetrate fire barriers , and are protected by features such as:
- fire doors
- shutters
- water spray fixed fire suppression systems
