What are demising walls?
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Walls that separate residential units from each other and from common areas.
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What are demising walls?
Walls that separate residential units from each other and from common areas.
What does compartmentalization in residential buildings mean?
They are divided into smaller, fire-resistant areas.
What kinds of vertical shafts exist in highrise buildings?
Pipe shafts, electrical shafts, mail chutes, laundry chutes, and trash chutes.
What is a penthouse in a highrise office building?
The top floor usually serving as a mechanical floor with equipment like fans and boilers.
What challenges can sloping terrain create for building floor design?
The ground floor may be higher or lower at different ends, complicating floor identification.
What type of floor plans do property managers often have for highrises?
8½ by 11 inch drawings showing core configuration and demising walls.
What is a common feature of hotel layouts compared to condominiums?
Hotels usually have a center corridor with rooms on each side, while condominiums have a defined core.
What is the definition of a highrise building?
A building with a distance from the ground to the top floor of at least seventy-five feet.
What are the two broad categories of highrises?
Commercial and residential highrises.
What does the officer seek from the security guard?
He asks if there is an elevator ready to take them up.
How are floors supported in lightweight concrete constructions?
By steel I-Beams or steel trusses.
How can mechanical floors affect the appearance of a building's height?
They have very high ceilings, making them appear as two levels from outside.
What are the two common types of residential highrises?
Hotels and condominiums.
What are the dangers of suspended ceilings in a fire situation?
They can fall, creating entrapment hazards for firefighters.
How does the sub-level floor numbering usually progress?
From the top down, starting with BI for the first level below ground.
What type of flooring construction might be used in highrise buildings?
Reinforced concrete or lightweight concrete on metal pan.
What construction method can be used for core walls?
Concrete or drywall over metal studs.
What is the primary function of slab penetrations in a building core?
To provide access for mechanical, electrical, and telecommunication services.
What types of dampers are commonly used in newer buildings for demising wall openings?
Automatic fire dampers that close when the floor goes into alarm.
Why might a main lobby be one level above ground level?
Design choices and aesthetic considerations.
What is the primary focus of the book?
Emergency systems in highrise buildings.
Where are main mechanical rooms typically located?
On a sub-level (below ground) or at the top of the building.
What designation is given to parking levels in buildings?
Levels P1 through P7.
What special fire protection systems are often used in telecom floors?
Preaction sprinkler systems or special gaseous extinguishing systems.
How do parking levels differ from tenant floors in highrise buildings?
They usually have a shorter slab-to-slab height and more substantial floor construction.
What should be checked regarding curtain walls?
Whether the floor/curtain wall gap is filled and covered.
What should be carefully fire-stopped in buildings?
Slab penetrations for pipes and electrical risers, as well as demising wall penetrations for conduit, cable, and air ducts.
What is a potential issue with fusible link dampers?
They can fail to close properly, allowing smoke to pass through before activation.
What type of ceiling is typical in high-rise office space?
A suspended ceiling consisting of a metal grid and ceiling tiles.
Why was the firefighter overwhelmed when the elevator doors opened?
Because they had arrived on the fire floor, which was filled with heat and smoke.
What happens to ceiling tiles during a fire due to updraft?
They can be lifted from the grid, increasing the entry of superheated gases.
What is a key characteristic that differentiates office floors from main lobbies in highrise buildings?
Main lobbies often differ in floor layouts, sprinkler valve locations, standpipe outlet placements, and ventilation configurations.
Why do firefighters consider residential buildings a greater life safety problem?
Because people are present in residential buildings 24 hours a day, engaging in various activities.
What should be noted about the main lobby's location?
Whether it is on street level or elsewhere.
Where are loading docks usually located?
At the back of the building or on a less visible side.
What areas are typically included within the core of a building?
Mechanical rooms, electrical rooms, telecommunication rooms, and restrooms.
What are demising walls?
Fire resistive walls extending from the floor slab to the bottom of the floor above, enclosing building cores.
How can the structure of a mechanical penthouse differ from other floors?
It often has a smaller floor area and lighter construction materials.
How did the firefighter determine which floor had the fire?
By counting the rows of windows on the exterior of the building.
What motivates the engine company officer in the scenario?
To impress the battalion chief by successfully extinguishing the fire.
What is the purpose of telecom floors in highrise buildings?
They support high-security telecommunication equipment and functions.
What type of building construction materials should be identified?
Concrete or steel frame.
What are demising walls commonly used for?
To separate different companies' spaces on multiple tenant floors, and enclose core walls and computer rooms.
How does smoke behave in a highrise building?
Smoke is free to move from level to level.
Where is the core usually located in a building?
Typically in the center of the floor area, but it can also be on one side or have multiple cores in larger buildings.
What materials can core walls be constructed from?
Concrete, masonry blocks, or drywall.
What should be done when the firefighter realizes they are on the fire floor?
Activate the Door Close button, select another floor to escape, and notify incoming companies of the correct fire floor level.
What often fills at least one floor in hotels?
Service equipment like air conditioning units, boilers, and laundry machines.
What is important for prefire planning in highrise buildings?
Reliable building information.
What is a key difference in design between commercial and residential highrises?
Commercial towers usually have greater average floor heights, while residential buildings are more compartmentalized.
What is the significance of pre-fire planning regarding building levels?
It helps firefighters have critical information during emergencies.
What materials can a curtain wall consist of?
Panels of glass, stone, or various other mediums.
What often compromises the compartmentalization provided by office walls?
The ceiling plenum is often open to fire spread.
Why are slab penetrations considered potential avenues for smoke and fire spread?
Because they can allow smoke and fire to travel between floors.
What is the purpose of fire-rated doors in demising walls?
To protect door openings from the spread of fire.
At what height are buildings typically considered highrises?
Buildings over six stories.
What are the two types of floor construction in highrises?
Poured-in-place concrete or lightweight concrete on metal pans.
What is a common characteristic of the first and second floors in highrise buildings?
They are often very tall and may appear to be more than two floors from the street.
What is often found in the Fire Control Room to aid firefighters?
A diagram of the building's levels posted on the wall.
What common mistake can occur when identifying the fire floor from outside?
Assuming fire from the thirty-fifth row of windows indicates a fire on the thirty-fifth floor.
How can core wall construction influence emergency situations?
It can impact forcible entry events or elevator emergencies.
What potential hazard does the return-air grill present during a fire?
It allows smoke, heat, and flammable gases into the plenum.
What issue do cubicle partitions create during firefighting operations?
They complicate search operations and hose line advancement in smoke.
Why is it beneficial to visit buildings prior to an emergency?
To document critical information that may be used in an emergency.
What types of occupancy should be identified in a highrise building?
Office, residential, or a combination of occupancies.
What materials are commonly used for the frame of highrise buildings?
Steel, concrete, or a combination of the two.
What type of elevator do they use for emergency operations?
A freight elevator in Independent Service mode.
What does the officer assume about the security guard?
That he knows how the elevators operate.
What is the common purpose of a loading dock in a building?
For moving furniture, equipment, and supplies in and out.
What are the primary functions of the core of a highrise building?
It contains various types of vertical shafts, including ventilation shafts, elevator shafts, and stairwells.
Why can firefighters have difficulty determining the fire floor level from outside?
Different heights and designations of floors can create discrepancies.
How do electric magnets function in relation to fire-rated doors?
They hold doors open and release them to close when the fire alarm system is activated.
How are modern condominium buildings typically constructed?
Around a center core containing elevators, stairwells, ventilation shafts, and electrical rooms.
Why are common areas in residential highrises usually air-conditioned differently than living units?
Common areas typically receive conditioned air from other floors through multiple level shafts, while living areas often have individual air conditioning.
What critical action does the officer take to identify the fire floor?
He counts the rows of windows to determine the fire floor.
What does the officer declare when he enters the building?
He announces the 12th floor as the fire floor.
What is often used to coat steel frames in highrise buildings?
A fire retardant coating, often asbestos-based in older buildings.
How can loading docks benefit firefighters during an emergency?
They provide convenient access points, especially when the front entry is unsafe.
What is a common designation for the second floor in highrise buildings?
It is often called 'Mezzanine,' with the third floor being Level 2.
What can make a ground floor appear to have two levels from the outside?
Having a very high ceiling.
What error did the firefighter make regarding the fire floor?
The firefighter mistakenly took the elevator to the fire floor instead of a safe location.
Do demising walls provide a fire barrier in the plenum above the ceiling?
No, they do not prevent the spread of fire.
What can happen when ceiling structure and cables fall during a fire?
It can lead to entrapment and has resulted in fatalities among firefighters.
What information about the building's floors should be gathered?
The floor designations from bottom to top.
Why do telecom floors require a guaranteed power supply?
To support critical, multi-million dollar per minute functions.
Why is it important to understand highrise construction for firefighters?
Various construction features are important for firefighting operations.
Why should floor designations not be taken for granted?
Because they can vary between buildings, especially for sub-levels.
What is a key characteristic of office walls within individual company spaces?
They are usually partition walls with open space above the ceiling.
How can miscounting floors lead to confusion for firefighters?
If firefighters count windows, they may mistakenly think the fire is on the 16th floor when it is actually on the 14th floor.
How does omitting floor numbers impact highrise marketing?
It can make a building seem more prestigious; for example, a fifty-story building sounds more impressive than a forty-story building.
What is the space above ceiling tiles often referred to?
The 'ceiling plenum.'
What are main mechanical floors like in commercial highrise buildings?
They are much taller, usually without ceilings, and contain boilers, chillers, huge fans, pipes, valves, tanks, and pumps.
What type of construction are highrise buildings typically made of?
Fire resistive construction.
What is the exterior skin of a modern highrise building called?
Curtain wall.
What space is often filled with fire-stop material in highrise buildings?
The space between the floor slabs and the curtain wall.
What unusual floor designation was mentioned in a Houston building's example?
The floor above Level 13 is designated as Level 13.5.
Why might Level 13 be omitted in a building's floor designations?
Because it is considered unlucky, making the building appear taller with a Level 14 above Level 12.
What implications can early miscommunication about the correct fire floor have?
It can lead to operational mistakes and has been involved in firefighter deaths.
How do openings in demising walls function for air return?
They allow return air to reach the mechanical room and may be equipped with dampers.
What should firefighters do if a fire is contained within demising walls?
Remove ceiling tiles around the demising walls to view horizontal ventilation openings.
