High-Rise Flashcards
Define high-rise building.
A building with either six or more stories or a building where the highest occupied story/floor is greater than 75’ from the lowest level of fire department vehicle access
In 1976 VA Uniform Statewide Building Code was modified to require what in highrises?
Fire control room
What construction type are most high rise buildings?
Fire resistive construction
What is reflex time?
The time needed to assess the situation upon arrival of the first units, gather info from the annunciator panel, identify and confirm fire floor, proceed to that floor, locate the fire on the floor and prepare to operate.
Residential High Rise Characteristics
Center hallways, numerous interior compartments and 24 hour occupancy
Commercial High Rise Characteristics
center core construction with circuit corridors around the core of the building and may have large, open expanses on each floor. Occupancy loads normally greater during business hours. Elevators, stairwells and mechanical rooms are located in the middle core of the building with offices or residential spaces making up the perimeter of the floor.
What are some concerns of atriums in high rises?
Difficult to control smoke conditions. Typically required to include full sprinkler protection, smoke exhaust systems and smoke curtains.
What may you find in buildings with long hallways?
Fire rated doors throughout the hallways length. If the hallways are sectioned off by fire doors you will typically find a stairwell and standpipe for each area
Pre February 1976 Buildings:
Typically steel and concrete, most are not sprinklered and do not have fire control rooms, modern fire alarms, or elevator control systems.
Features common to older structure include:
- Compartmentalized office and residential spaces with mazelike corridors
- Non-compartmentalized open floor plans for commercial office occupancies
- Presence of window AC units and/or lack of building-wide heating, ventilation and HVAC systems
- Conventional windows that may be opened
- Lack of suspended ceilings (less hidden void space)
- Steel structural members encased in concrete
- Exterior, masonry walls that are tied directly into each floor
- pre- or post-tensioned concrete floors
- reinforced concrete columns
Post February 1976 construction
Fire resistive construction with the following required fire protection features:
- Class III standpipe–2 1/2 in discharges with 1 1/2 reducers
- A compartmentation option existed for buildings built prior to April 91’, however, the vast majority of post 1976 buildings are either partially or fully sprinklered
- Firefighter service to elevators
- HVAC system capable of exhausting smoke
- 2 means of egress per floor
- Fire warning system
- building communications system
- fire control room
- standby and emergency power systems
All occupied high rises in NOVA have (with few rare exceptions):
- At least two approved exits from each floor
- enclosed stairwells
- some type of smoke control system or compartmentation. This includes windows that can be opened, tempered glass panels on at least two sides of the building that can be broken out, or a modified HVAC system that can exhaust smoke to the outside without contaminating other floors
High rise roofs:
may be of much lighter construction that the floors, It may consist of an insulated metal deck roof or be of the same construction as the floors below, but with a weather barrier installed
Each fire station should ensure that preplans exist for the high-rise structures in their area. When possible a copy of this should be placed?
In the fire control room at each building
What is a bulkhead ref highrise buildings?
Bulkhead is when the stairwell extends to the roof in an enclosed entrance way. (looks like shed on roof)
How is roof access obtained?
- hatch
- bulkhead
- penthouse machine room
How are curtain walls attached and how can the contribute to vertical fire spread?
The are mounted to the floor sections or frame of a building (bolted or welded brackets), gaps of 6-12” are common between the floor and exterior wall. Fire stops are required however their effectiveness is questionable. Expect vertical extension through these spaces as well as downward, including the plenum space on the floor below
Intumescent coating?
Spray on fireproofing often used as fire resistive measure for floor/ceiling support systems
Buildings built prior to 1980 may what kind of sprayed on fiber?
asbestos
How much air can low mass concrete (formed concrete) contain?
Up to 20%
How much lighter is formed concrete than traditional concrete?
10-88% lighter
When can failure due to fire occur in light weight concrete?
Failure occurred at 80% of the designed load after 45 minutes of fire exposure. Thermal cracks appear within 14-16 minutes of fire exposure.
Buildings with fixed windows are required to have certain windows that can be broken in the event of an emergency, how are they marked?
Maltese cross or a fire helmet etched in the lower corner of the pane, some may also be opened with special keys or devices
What are windows in highrises made of?
- Plate glass
- Tempered glass
- lexan
Doors leading from the stairwell to the hall, roof or mechanical room may be locked above what floor?
Lobby or first floor
What is a stair door unlock switch, and where is it likely located?
A switch that will simultaneously unlock without unlatching stairway doors, may be in the fire control room
Isolated stairs
Usually have individual entrances and access only one section of the building
Scissor stairs
Independent stairwells on either side of the core. Each stairwell may only serve every other floor.
Accommodation stairs (access, convenience stairs)
Open, unprotected stairways leading from floor to floor within a single occupant’s space
Post 1976 construction should contain what in the stairways
Hard-wired communications linked with the fire control room
What does the presence of a security gate indicated in a stairwell?
The gate denotes the last floor with an exterior entrance
Yard stanchion?
FDC mounted away from the building in the surrounding yard
Hydrants should be found how close to FDC in post 1976 construction?
Generally within 100’ of standpipe and sprinkler FDCs
Pressure-reducing valves should be bypassed for fire department use, how can this be accomplished?
By breaking the “L” shaped arm that restricts the riser wheel
The fact that HVAC ducts at perimeter windows of the building may be fed fresh air from the ducts located in the ceiling of the floor below, allows?
Rapid fire extension
What is a damper? (HVAC systems)
A device controlled by fusible links that limits fire spread through ducts.
In a flat belt design elevator system where is the machinery mounted?
In the elevator shaft and/or on top of the elevator car. Not in the traditional elevator room.
Blind shaft elevators?
Only serves a specific portion of the building and has no openings on other floors.
Define fire control room
A room used for any system in a high-rise where detection, fire protection, air handling systems and communication are centralized for fire department use.
Fire Control Rooms will contain the following:
- Annunciator panel(s)
- Telephone communication systems
- Public address systems
- Pressurization/smoke control systems
- HVAC
- Emergency generator and stand by power status
- Automatic door unlocking systems
- Telephone with an outside line
- Key box with multiple sets of keys
- Building plans
In high rises PA system speakers are required in:
Hallways, elevators, stairwells, rooms, tenant space exceeding 1000sq ft, and all dwelling units
Do office buildings or hotel/residential high rises have a greater potential for horizontal and vertical fire extension?
Office buildings
If more than two floors above the fire still contain occupants, a search and rescue evacuation branch should be established, who leads it?
A chief officer
If a small scale evacuation is required what is the group charged with the evacuation?
Search and Evacuation Group
Mushrooming?
Typical smoke movement found in residential and commercial structures without impact from environmental conditions. Results in smoke rising upward from the fire floor until it reaches the roof/veiling level. Smoke then banks off of the roof/ceiling and migrates downward, back towards the fire floor.
What does cold smoke signify?
Fires brought under control by sprinkler systems
Stack effect?
Natural movement of air within a relatively tightly-sealed building due to the temperature difference between the air on the inside and outside of the structure. Stack effect more noticeable in winter due to the considerable difference between inside and outside temperatures.
Reverse Stack Effect
Stack effect can be reversed, resulting in the movement of air in a vertical shaft, due to the outside temperature being higher than that inside
What is the most effective method for controlling and preventing flashover?
Cooling the overhead area.
Wind driven fires can exist with winds as low as?
10-20mph
What five conditions must exist for a wind driven fire to occur?
1-Fire in the structure
2-Failed or open window to the outside in the fire area
3-Presence of wind on the exterior of the structure
4-Failed or open door to area leading into a common hallway (usually caused by the fleeing occupant leaving the door open)
5-Unobstructed path to an outlet for the fire to vent (open apartment door across the hall, open stairwell door, or open bulkhead door)
To aid in size up of a wind-driven fire, personnel should be aware of:
- presence and direction of wind
- failure of windows to the fire area
- lack of smoke/flames pushing from the failed window and/or intermittent smoke and flames pushing from the failed window
- presence of a large volume of fire within the fire area
What must the first due truck advise immediately upon their arrival to the fire floor?
If they can close the door to the fire area
What alternative tactics did NIST show for when personnel cannot make entry into the fire area?
1) an exterior attack using elevated master streams through the fire apartment window
2) exterior attack via portable ground ladders
Contents of high rise buildings have a heat release rate that allows the fire to double in size how often?
Every 90 seconds
Metal door that opens outward may be an entrance to?
An electrical vault
In buildings under construction how many floors below the finished floor must a riser be?
Two floors
If concrete work is underway and the formwork is in place and burning can firefighters be committed for interior ops?
No
Five basic points of the operational plan for high-rise fires?
1) Determine fire floor
2) Verify fire floor
3) Control occupants
4) Control of building systems
5) confine and extinguish the fire
At a minimum what building systems must be brought under FD control?
Control of elevators, fire pump and any air handling systems
What is the fire load in general office space?
7.7 pounds per square foot (psf)
Fire load for a conference area?
5.9 pounds per square foot
Fire load in a file area?
16 pounds per square foot
What should Engine crews wait for before opening doors into the fire area?
Wind conditions reported by the vent group who should open a window on the same side as the fire to check conditions
What position in a high rise fire will the second chief likely assume?
Fire attack group supervisor
What is the fire load in residential highrise occupancies is considered low and requires a fire flow of?
10gpm per 100sqft involved
How many engine companies should be paired up to operate a 2 1/2 in a high rise situation?
2 engine companies
Required fire flow for commercial high rise occupancies?
20gpm per 100sqft involved
A reported vehicle fire in a parking garage attached to a high rise should be treated as?
A high rise building fire
With parking garage ventilation systems will activate upon receipt of an alarm?
Large fans, if they don’t automatically start they will need to be controlled manually
In a below grade garage what can help keep the attack stairwell clear of smoke?
A combination of the garage ventilation system and PPV
What is the minimum initial alarm assignment for a high rise fire?
5 engines 2 trucks 1 squad 2 BCs 1 EMS super 1 Command Aide 1 EMS unit
When can elevators without fire service control be used?
Only after the first engine and truck/squad have climbed the stairs and assessed the fire floor situation.
How many companies can be in an elevator car together?
2
If the fire is reported on a floor at this point or below, personnel should walk up.
6 floors above ground level or lower
If there is smoke in the lobby will the elevators recall to the lobby.
No, they will recall to an alternative location.
The first in engine should wait for what company before proceeding to the fire floor unless there is a significant delay.
1st due special service.
If the fire is below grade in a highrise where should the RIT position?
Outside the IDLH but in close proximity such as one floor above but not below.
Where should the first due truck position for a highrise?
Side alpha unless the fire location can be readily identified then park on fire side of building.
If the first due truck is a tower ladder can they ride the bucket to the fire floor?
Yes, but only after communicating it with command and the first engine.
What are the search priorities for a residential highrise?
Fire unit
Exit hallways
Adjacent units and the units across the hall from the involved unit
Search priorities for non-residential highrises?
- Immediate fire area and floor
- Floor above the fire area
- The top floor including the hallways, stairwells and elevators leading to these areas
- Floors between the floor above the fire and the top floor
If the second due truck is a tower and the fire is within reach of the aerial what should the driver do?
Raise the tower to the level of the fire via the bucket and remain ready for placement as needed.
Who establishes the base area?
6th due engine, the 6th due engine driver becomes the base officer
How many spare cylinders should each company on the second alarm or greater bring with them?
2 spare cylinders per unit
What is the minimum equipment engine companies reporting to staging shall bring?
100’ 1 3/4 and 100’ 2 1/2 highrise packs. Plus their two spare cylinders per unit.
What is lobby control responsible for?
- unit tracking and recording
- elevator operations
- building systems control
- stairwell identification
- coordinating civilian evacuation of the building
What are the search designation markings?
/ means search is underway in a room/apt/office etc.
X followed by unit identifier indicates it is complete
What are the three basic ventilation tactics for a highrise?
- horizontal through the windows
- vertical through the stairwells
- use of the buildings HVAC system
In a commercial highrise what type of ventilation should not be used?
Horizontal
What vertical shaft is the least desirable option for ventilation?
Elevator shafts
If the elevator shaft is to be used for ventilation what must be done?
- ensure adequate opening at the top
- move the elevator car below the floors to be vented
- open and secure hoist way doors on the floors to be vented
- secure ladder across the front of all open hoist way doors
When should a search or evacuation group be activated in a highrise fire?
If there are more than two floors above the fire that still contain building occupants
Where should the search and evacuation post be set up?
At least two floors above the highest fire floor near the evacuation stairwell
What is the minimum staffing for stairwell support?
Firefighter positioned every two floors
What is the priority equipment to get moved upstairs by stairwell support?
Air cylinders. Anticipate no more than 15-20 minutes per cylinder during firefighting operations
What should stairwell support personnel expect to deliver to the fire area?
- cylinders
- extra packs
- deployment of supplied air line from mobile air unit (250’)
- water
- standpipe packs
- flashlights/lighting
- radio batteries
What is the medical unit in a high rise fire responsible for?
Treatment and care of fire department personnel
Where is the medical unit located?
One floor below staging, rehab is here too
