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High-Rise Buildings
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Learning Objectives (1 of 18)
• Describe the magnitude of the high-rise fire problem in terms of number of fires, number of fire fatalities, and property loss.
• Explain the effect the loss of life and property at the World Trade Center on September 11, 2001 has on the statistical analysis of high-rise fires in relation to loss of life and property in high-rise buildings.
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Learning Objectives (2 of 18)
• Define a high-rise building from a fire department perspective.
• Explain elevator recall and its advantages during a fire emergency.
• Enumerate the responsibilities of lobby control.
• Explain why using an elevator during a fire emergency is a calculated risk.
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Learning Objectives (3 of 18)
• List and discuss the seven rules for safety when using an elevator during a high-rise structure fire.
• Describe the process of using an elevator under fire department control.
• Explain the duties of stairway support and when it should be used.
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Learning Objectives (4 of 18)
• Compute the number of fire fighters needed to staff stairway support for a fire on the 30th floor of a high-rise building where the elevators are unsafe to use.
• Identify negative and positive aspects of using helicopters at a high-rise building fire.
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Learning Objectives (5 of 18)
• Construct a chart showing the angle of deflection for fire streams operated from the exterior into an upper floor of a high-rise building.
• Compute the approximate pump discharge pressure needed to supply a hose stream operating on the 20th floor.
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Learning Objectives (6 of 18)
• List four occupancy types that are commonly found in high-rise buildings.
• List five special considerations when developing a pre-plan for a high-rise building.
• Compare old-style tower construction to modern, planar-style high-rise buildings.
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Learning Objectives (7 of 18)
• Define and explain the advantages of a smoke-proof tower.
• Discuss methods that can be used to maximize the limited stairway capacity in a high-rise building and how fire department operations can hinder evacuation.
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Learning Objectives (8 of 18)
• Describe an EVAC system and identify the advantages and disadvantages as compared with other notification systems.
• Explain the difficulties in determining the location of the fire from the exterior of a high-rise building.
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Learning Objectives (9 of 18)
• Develop a high-rise decision tree with decision points addressing fire location, size, and elevator availability.
• Explain how heat affects smoke movement in a high-rise building.
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Learning Objectives (10 of 18)
• Define stack effect and explain the conditions necessary for positive and negative stack effect.
• Explain how wind affects the neutral pressure plane.
• Discuss the importance of extinguishment to life safety in a high-rise fire.
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Learning Objectives (11 of 18)
• Explain what is meant by a “wrap-around” fire.
• Describe the hazards involved in ventilating upper floors by removing window glass and how to protect fire fighters and civilians on the street below.
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Learning Objectives (12 of 18)
• List pathways for floor-to-floor fire extension in a high-rise building.
• Define “lead time” and extrapolate the estimated lead time for a fire on the 40th floor of a high-rise building when elevators are unavailable.
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Learning Objectives (13 of 18)
• List practical forms of non-radio communication that can be used at a high-rise building fire.
• Discuss when interior and exterior staging would be used at a high-rise fire.
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Learning Objectives (14 of 18)
• List the duties of the interior staging officer.
• List the duties of lobby control.• Compare and contrast factors that
affected fire operations at the One Meridian Plaza fire in Philadelphia and at the First Interstate Bank Building fire in Los Angeles.
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Learning Objectives (15 of 18)
• Evaluate the number of possible fire deaths in a high-rise building at the Peachtree Plaza fire in Atlanta based on the number of actual civilian fire deaths and probable deaths had the fire been on a higher floor.
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Learning Objectives (16 of 18)
• Explain the negative effects of operating an exterior stream into a high-rise building.
• Compare the designed “accidental aircraft” impact at the World Trade Center to the actual impact of the aircraft on September 11, 2001.
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Learning Objectives (17 of 18)
• Describe the conditions leading to structural collapse at the World Trade Center.
• Describe how a “convergence cluster” could affect search-and-rescue operations at a high-rise building.
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Learning Objectives (18 of 18)
• Evaluate operations at a simulated high-rise fire in your response area.
• Size-up, develop an incident action plan, assign units to carry out the plan, and develop a NIMS organization for a simulated high-rise fire scenario.
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Overview (1 of 2)
• High-rise fires represent an extraordinary challenge.
• The chance of rescuing victims from the exterior is near zero once the fire is above the reach of aerial apparatus.
• Tactics and strategies are the same that apply to any other structure fire.– With considerations because of the height of the
building
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Overview (2 of 2)
• The overall number of fires, civilian fire deaths, and property loss seems to be trending downward. – Probably due to more buildings being
sprinkler-protected
• A sprinkler-protected building is a safer building for fire fighters and occupants.– However, fire departments should not
place total reliance on the sprinkler system.
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High-Rise SOPs
• Incident scope can be reduced through pre-planning and code enforcement.
• Special tactics will be needed to control fire forces.
• Use of NIMS and high-rise SOPs can ensure successful operations.
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High-Rise Definition
• Most codes define a high-rise in terms of height and/or stories.
• Fire departments think of a high-rise as being beyond the reach of available aerial apparatus.
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Logistics
• Logistics and access problems increase with height.– The more floors above the fire, the more
people are likely to need assistance, and the more fuel there is to burn.
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Fire Fighter Safety (1 of 2)
• Risk increases in proportion to the height of the building and the height of the fire above grade level.
• Interior stairs are the only means of egress available for fires above the reach of aerial apparatus.
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Fire Fighter Safety (2 of 2)
• Good tactics and safety cannot be separated.
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Lobby Control
• An assignment in which a crew is responsible for duties related to managing the stairways, elevators, and the HVAC systems
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Fire Fighters’ Use of Elevators
• Fire-ground logistics will be improved if fire fighters can safely use elevators.
• Department SOPs should address:– Circumstances safe/unsafe use– Alternative measures for getting needed
equipment to the fire floor when elevators cannot be safely used
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Elevator Safety
• Calculated risk; should be avoided unless it will substantially improve operations
• Use stairways for fires on lower levels.
• Only used under the close supervision of lobby control
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Split-Bank Elevators
• Divided into several zones to allow access to specific floors of the building
• Should be included in pre-plan information
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Split-Bank Elevators
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Elevator Recall
• A safety feature designed to send elevators to ground level when the fire alarm is activated
• Elevators remain locked at the ground level until fire fighters arrive and use a key to place the elevators on fire department service.
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Safety Rules (1 of 2)
• Do not use an elevator of questionable safety or for a fire on a lower level.
• Never take an elevator directly to the fire floor or above.
• Place the elevators under independent (fire department) control.
• Control all elevator cars in multiple hoistways.
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Safety Rules (2 of 2)
• Never overcrowd elevators.
• Wear personal protective clothing, including SCBA, and bring forcible entry tools.
• Send equipment rather than fire fighters on elevators.
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Stairway Support
• One or more fire fighters on every other floor– Shuttle equipment up through the building
• Used when using elevators is not safe
• One of the first assignments given when the fire is on the upper floors in a building without elevator service
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Life Safety (1 of 2)
• A method of indicating areas searched should be part of the department’s high-rise SOP
• Rescue and extinguishment teams should carry tools to force entry when necessary.
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Life Safety (2 of 2)
• The primary search should assure that all elevators are accounted for and checked for occupants.
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Helicopter Use (1 of 2)
• Extremely dangerous, often unnecessary
• Requires constant training and justification
• Can be used for rescue or reconnaissance
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Helicopter Use (2 of 2)
• Can create additional risks due to thermal updraft
• Risk-benefit analysis must be conducted.
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Partial Evacuation
• Can be decided upon in advance• IC may decide it is best to defend-in-
place• Depends on available fixed fire
protection• Only the occupants in affected areas
are evacuated from the building.– Others are told to remain in place.
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Calculated Risk
• Any time a decision is made to leave occupants inside a burning building, the IC is taking a calculated risk.
• The IC is depending on:– Construction features– Fixed fire suppression systems– Manual suppression efforts
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EVACS (1 of 2)
• Emergency Voice/Alarm Communications System– Uses recorded messages to notify
occupants of a fire– Provides specific directions for reaching
places of safe refuge within the building
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EVACS (2 of 2)
• Will also have manual overrides that allow fire fighters or building management to direct the evacuation
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Extinguishment• Exterior defensive fire control tools are
ineffective above the 8th floor.
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Standpipe Systems
• Smooth-bore or low-pressure nozzles should be used.
• Reduction in friction loss = increase in nozzle pressure
• System pressure can be boosted and water supply increased by pumping into fire department connection.
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Command Post
• Lobby may not be preferred location.– Should be isolated from disruption and
protected from fire and products of combustion
• Location should provide good communications and ample work space.
• Location should be communicated to all responding companies.
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High-Rise Pre-Plans
• Should address:– Elevator operations and elevator key location– Access/egress issues– Standpipe operations– Floor layouts for each floor– Ventilation concerns (e.g., HVAC system, special
windows, etc.)– Procedures or operations that are unique to the
building
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High-Rise Construction (1 of 2)
• Old style high-rise tower design– Heavy masonry construction– Seldom sprinklered– Better compartments
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High-Rise Construction (2 of 2)
• New style high-rise planar design– Structural steel frame– May be sprinklered– May be core construction– Central HVAC
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Central Core Layout• Stairways are located in the center of
the building (usually found in new-style high-rises).
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Side Core Layout• Stairways are located away from the
center of the building.
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Smoke-Proof Tower
• A stairway designed to be separated from the building by a landing– Built as a separate structure– Creates a separation that will limit the
spread of smoke into the stairway– Keeps stairway clear for evacuation– Could be pressurized to reduce chance of
smoke infiltration
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High-Rise Size-Up (1 of 2)
• Very difficult due to nonexistent or misleading visual information– Finding the fire can be difficult.– Fire can be present without any visual
signs.– Exterior visible evidence may be
unreliable.
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High-Rise Size-Up (2 of 2)
• Occupant reports may be unreliable.– Often located many floors above the fire
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Life Hazard Potential (1 of 2)
• The IC must match the occupancy classification to time factors.
• Working hours vs. non-business hours – Occupant load varies greatly
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Life Hazard Potential (2 of 2)
• The average office building has one person for every 100 ft2 (9 m2).
• Pre-planning aids in determining the life safety problem.
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Dispatch Information (1 of 2)
• Validity depends on alarm type.
• Follow-up calls from the public repeat and verify information already received:– Reporting people trapped– Requesting evacuation instructions– Report fire conditions in specific areas of
the building
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Dispatch Information (2 of 2)
• This information should be immediately relayed to the IC. – The IC should notify the appropriate
personnel to evaluate the situation.
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Smoke Movement
• Affected by weather conditions and fire intensity
• Fire intensity and size– Determine the extent gases are heated and
how high they will rise inside the building – Heat energy in low structures causes gases
to rise to highest level of building.– Gases stratify in high-rise buildings at a
point of equilibrium.
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Stack Effect
• The vertical airflow caused by temperature differences within and outside the building
• Results in unpredictable behavior of smoke
• Chances of stratification are less on a cold day versus warm day.
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Neutral Pressure Plane (NPP)
• The point in a high-rise where air is neither moving in or out.– Below the NPP, air is moving into the
building.– Above the NPP, air is moving out of the
building.
• The NPP is affected by heat from the fire, the stack effect, and wind.
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Incident Action Plan
• Incident priorities remain the same regardless of the type of structure. – Life safety– Extinguishment– Property conservation
• In a high-rise, ventilation and evacuation options are limited, so confining and extinguishing the fire is critical.
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Stairways
• Fire fighters may be trying to advance up while occupants are attempting to evacuate down.
• It is not always best to have all of the occupants in the stairways at the same time. – People on the fire floor and floor above are
in the greatest danger and should be evacuated first.
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Ventilation (1 of 3)
• Should be done by using reversible methods– Breaking windows high above grade level
creates a serious hazard below.
• Opening a window is much preferred to breaking it. – If a window is opened and the effect is
negative, it can be closed.
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Ventilation (2 of 3)
• Most high-rise buildings have sealed windows that cannot be opened.– Fire codes may require that a percentage
of the windows be operable or made of tempered glass so that manual ventilation is possible.
– This should be noted on the pre-incident plan.
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Ventilation (3 of 3)
• The operation of the HVAC system is usually reversible. – Should be shut down if the HVAC system
does not have the desired effect or spreads the smoke
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Interior Exposures
• All floors above the fire are exposures and need to be checked for extension.
• In modern buildings with curtain walls, fire can extend upward inside the building near the exterior wall.
• Fire also can spread upward through:– Stairways and elevator shafts – Pipe chases and utility penetrations
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Property Conservation
• Should be considered early in the incident
• High-rise office buildings may contain valuable contents:– Computers and other office equipment– Important files and documents
• The greatest property conservation exposure is often downward.
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Lead Time
• ICs must understand that it takes time to complete assignments.
• Lead time is impacted greatest by the level where the fire occurs, especially when elevators are not available.
• The IC must be able to anticipate needs and assign resources in advance.
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NIMS
• NIMS should be used at every structure fire.
• Proper use of NIMS tests a department’s training, pre-incident planning, and discipline.
• The span of control can be quickly exceeded at a major high-rise fire.
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Communications (1 of 2)
• Simplified by use of NIMS
• Division: used to identify a geographic location or assignment
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Communications (2 of 2)
• Most frequently cited problem at major operations– Breakdown may occur if separate
frequencies or systems are not provided.
• High-rise buildings make radio use difficult.
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Base: Exterior Staging (1 of 2)
• A location where support equipment and personnel are kept on the exterior of the building– Can also be called exterior staging
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Base: Exterior Staging (2 of 2)
• May be established near the fire perimeter– Generally limited to fires on lower floors
• The staging area is normally moved inside the structure during a high-rise fire.
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Interior Staging (1 of 2)
• Established to provide a readily available reserve force
• Normally two or more floors below the fire
• The interior staging area could be identified as interior staging or as the resource area.
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Interior Staging (2 of 2)
• Can be the site for a REHAB area
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Staging Officer Duties (1 of 2)
• Reports to the operations section
• Maintains records of the companies
• Maintains reserve personnel
• Requests additional resources
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Staging Officer Duties (2 of 2)
• Maintains an adequate supply of air cylinders and other equipment
• Supplies first aid equipment and medical services
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Lobby Control Duties (1 of 2)
• Controls, operates, and accounts for all elevators
• Assists in incident command post operations
• Locates and controls all interior stairs
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Lobby Control Duties (2 of 2)
• Directs incoming companies to the proper elevator or stairway
• Consults with the building engineer
• Controls the HVAC system
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Summary (1 of 6)
• The threat from high-rise fires is real.
• The chance of a serious fire is much greater in the non-sprinkler-protected, modern high-rise.
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Summary (2 of 6)
• Older buildings are constructed using massive structural members to support the structure and to provide fire barriers within the structure.
• A working fire in a high-rise can threaten thousands of occupants.
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Summary (3 of 6)
• The most effective way to extinguish a high-rise fire is by mounting an offensive attack.
• Attacking the fire from the exterior places fire fighters and occupants who are still inside the building in great peril.
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Summary (4 of 6)
• Using fire resistive structural features to contain the fire is preferable to an exterior attack.
• Fires on the upper floors of a high-rise building will often be beyond the reach of aerial devices.
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Summary (5 of 6)
• Occupant evacuation is usually limited to the interior stairs that can quickly become overcrowded.
• As the level of the fire floor increases, reliance on the standpipe system also increases.
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Summary (6 of 6)
• Getting resources to the places they are needed is complicated.
• The lead time dramatically increases for a fire on an upper floor if the elevator is not safe to use.
