BOOK 100 HIGH RISE MANUAL CHAPTER 6 VENTILATION Flashcards
A downward draft, or “_____________ effect,” becomes more pronounced when outside temperatures are higher.
Reverse stack effect
These vertical passageways provide excellent channels for the travel of fire and smoke, and are also utilized by occupants and Fire Department personnel to exit or access the interior floors.
Stairshafts and elevators
Stairshafts in high-rise buildings constructed after ____ are required to employ a shairshaft ventilation system.
1974
The fans must provide not less than __ cubic feet per minute while maintaining a positive pressure of not over __ lbs. on interior doors.
50
25
HVAC systems can form natural channels for the distribution of smoke within a building. These systems can be operated by _________ or ______ systems.
Manual or automatic
a high-rise building will “_____ ________” (movement of air, smoke, etc.) between the floors and into stairshafts.
Leak internally
Most high-rise buildings can be classified as “________ _______” (external glass panels are not openable).
Sealed buildings
These _____ systems are capable of retaining smoke, heat, and fire gases until they are manually ventilated to the outside environment.
Hvac systems
Smoke can travel between floors due to different types of construction such as unsealed openings, spaces or cracks between floors, and “______ _______” construction (openings utilized for pipes, elevators shafts, electrical alleys, etc.).
Poke through construction
Additionally the pressure generated by a fire (up to _____ times atmospheric pressure) will force smoke through these openings and may contaminate other floors or stairshafts within the building.
Three times
_______ of smoke and fire gases occurs as heat and smoke travel vertically within a building. These products of combustion will rise through any available vertical opening, cooling as they rise, until the temperature is equal to the temperature of the surrounding air.
Stratification
This stratification of smoke and fire gases generally serve as a “___” for other products of combustion which will tend to bank down below the stratified smoke and horizontally spread to other portions of the building. This process is common in vertical stairshafts.
Lid
__________ is a condition caused by smoke and fire gases that cannot vertically escape a building. Smoke and fire gases will rise to the highest level possible and then begin to bank down and fill all available spaces
Mushrooming
Open passageways created by _____ that have been opened or inadvertently “left open” will allow fire and smoke to travel horizontally and/or vertically to additional areas within a building.
Doors
Openings created by ______ that have been broken, removed, or opened will allow fire and/or smoke to travel horizontally through the interior of a building.
Windows
Openable windows, what era
Pre 1960
Post –1960 – Tempered glass on at least ____sides of the building. (At corners, and at ___-foot intervals or less.
Two sides
50 foot intervals
Post-1974 – Tempered glass on ____ sides of the building. (At corners, and at ___-foot intervals or less.)
4 sides
50 foot
Tempered glass windows are identified by___-inch luminous or reflective decals in a lower corner which indicate they are “_______________”
3 inch
For fire department use
What may be substituted for tempered glass
Openable windows, mechanical smoke removal systems
Post_____Requirement of Smoke Control Systems (Uniform Building Code) in high rise buildings has eliminated the requirement of the installation of tempered glass.
Post 1996
Many HVAC systems incorporate remote controlled
______ at the supply and return ducts on each floor.
Dampers
These dampers can be ______ to prevent heat loss during periods when the building is unoccupied (energy conservation), and can be opened to supply “________” air to floors within the building as necessary.
Closed
Conditioned
Unless the HVAC system is contributing to the spread of fire or smoke throughout the building, it should be left in the ____ (________) position.
On operating position
provide natural channels for the flow of smoke and fire within a high-rise building.
Stairshafts
For ventilation purposes, stairshafts can be placed in two categories:
- Stairshafts that open to the _______ only of a building and provide ______ _____
- Stairshafts that open to the ________ of a building and provide roof access
Interior
Roof access
Exterior
the natural air flow within building stairshafts is virtually static in buildings up to ___ stories. Buildings over ___ stories will naturally flow minimal amounts of air in an upward direction.
25
25
Natural vertical air currents of _____ to ____ mph, that flow upward in stairshafts, can be created by simply opening a door at the bottom and roof levels of a stairshaft.
Three to six
________ _______ created by Fire Department blowers can effectively create or augment the natural flow of air in a stairshaft and result in the discharge of contaminants within a stairshaft by pressurizing the ground level entrance opening to the stairshaft and removing the contaminants through the smoke control dampers (if present) at the top of the stairshaft and/or opening the roof level door.
Positive pressure
Water turbine blowers produce significantly less ______ and will provide more than _____ the cubic feet of air per minute that a like-sized gasoline powered blower. Water turbine blowers can be requested through____
Less noise
Twice
MFC
High-rise buildings constructed after 1974 are required to employ an emergency smoke control system that is comprised of the following components:
Pressurized Stairshafts
Mechanical Smoke removal system
Tempered glass or openable windows
When the building control room or fire control station has been located , check the status of the following
Smoke indicators for potential location and extension of fire
Elevators
HVAC SYSTEM
Building stair shaft pressurization fans
Emphasis should be placed on determining the stairshafts that open to the roof of the building. These stairshafts can be easily cleared of contaminants, facilitating the use of the stairshaft for ________, _______, or _______ operations.
Evacuation
Access
Ventilation
shall be responsible for ensuring that stairshafts are pressurized. Primary emphasis shall be placed on the stairshaft utilized by the Fire Attack Team or stairshaft used to access Staging.
Lobby control
Regardless of the size, portable blowers should be placed __ feet to __ feet back from the doorway and angled back at least __ degrees.
4 to 6
5 degrees
Placing fans in a ___shape is more effective than placing them is series
V shape
Placing portable fans inside the building ___________floor is a way to generate pressure differentials to increase the effectiveness of positive pressure in tall buildings.
Below the fire floor
Vertical ventilation by opening the door to stair shaft and opening a door at the top of the stair shaft the Stairshaft pressurization fans may be utilized “____ or _____” blowers for this operation
With or without
______ ventilation of a contaminated floor in a high-rise building can be effectively accomplished by utilizing blowers or a combination of blowers and stairshaft pressurization fans to pressurize a stairshaft and then directing the flow of pressurized air across the floor to be ventilated
Cross ventilation
Cross ventilation directs the flow to
Windows or to an opposing stairshaft that opens to the roof
If windows must opened/broken for ventilation purposes, utilize the windows on the _______ side of the building, if possible.
Leeward
The preceding cross ventilation operations are effe ctive up to ___ floors in a high-rise building.
25
If it is necessary to cross ventilate floors above the 25th floor, it may be necessary to utilize an additional _______ in the pressurized stairshaft to supply additional pressurized air to the floor to be ventilated
Blower
