Chapter 4 Flashcards
Means of Egress
Continuous and unobstructed path of exit travel from any point in a building or structure to a public way; consists of three separate and distinct parts: exit access, exit, and exit discharge.
Convenience Stair
Stair that usually connects two floors in a multistory building.
Tread
Horizontal face of a step.
Riser
Vertical part of a stair step.
Run
The horizontal measurement of a stair tread or the distance of the entire stair length.
Rise
Vertical distance between the treads of a stairway, or the height of the entire stairway.
Landing
Horizontal platform where a flight of stairs begins or ends.
Products of Combustion
Materials produced and released during burning.
Exterior Stairs
Stairs separated from the interior of a building by walls.
Fire Escape
Means of escaping from a building in case of fire; usually an interior or exterior stairway or slide, independently supported and made of fire-resistive material.
Smokeproof Stair Enclosures
Stairways that are designed to limit the penetration of products of combustion into a stairway enclosure that serves as part of a means of egress.
Passive Smoke Control
Smoke control strategies that incorporate fixed components that provide protection against the spread of smoke and fire. Passive smoke control components include fire doors, fire walls, fire stopping of barrier penetrations, and stair and elevator vestibules.
Escalator
Belt driven moving stairs that move in one direction at a fixed rate of speed.
Elevator
Vertical traveling mechanical system used to transport people and items in a multistory building.
Hoistway
The vertical shaft in which the elevator car travels; includes the elevator pit.
Alternating Current (AC) Circuit
Electrical circuit in which the current can move through the circuit in both directions and the flow can be constantly reversing.
Direct Current (DC) Circuit
Electrical circuit in which the current moves through the circuit in only one direction.
Machine Room-Less (MRL)
Elevator hoistway that includes all components, including motors, mounted within the hoistway itself to eliminate the need for a machine room at the top of the hoistway. The elevator controls may be located remotely from the elevator system.
Dumbwaiter
Small freight elevators that carry items, not people, and generally have a small weight and size capacity.
Elevator Pit
Depression at the base of an elevator hoistway that contains equipment and maintenance access.
Shear Wall
Wall panels that are braced against lateral loads. May be load bearing or nonload bearing.
Mushrooming
Tendency of heat, smoke, and other products of combustion to rise until they encounter a horizontal obstruction; at this point they will spread laterally until they encounter vertical obstructions and being to bank downward.
Blind Hoistway
Used for express elevators that serve only upper floors of tall buildings. There are no entrances to the shaft on floors between the main entrance and the lowest floor served.
Utility Chase
Vertical pathway (shaft) in a building that contains utility services such as laundry or refuse chutes, and grease ducts.
Refuse Chute
Vertical shaft with a self-closing access door on every floor; usually extending from the basement or ground floor to the top floor of multistory buildings.
Pipe Chase
Concealed vertical channel in which pipes and other utility conduits are housed. Pipe chases that are not properly protected can be major contributors to the vertical spread of smoke and fire in a building. Also known as Chase.
Heating, Ventilating, and Air Conditioning (HVAC) System
Mechanical system used to provide environmental control within a structure, and the equipment necessary to make it function; usually a single, integrated unit with a complex system of ducts throughout the building. Also known as Air Handling System.
Cupola
A type of rooftop projection historically used for ventilation and lightning, and modernly added for aesthetics.
Return-Air Plenum
Unoccupied space within a building through which air blows back to the heating, ventilating, and air conditioning (HVAC) system; normally immediately above a ceiling and below an insulated roof or the floor above.
Smoke Damper
Device that automatically restricts the flow of smoke through all or part of an air-handling system; usually activated by the building’s fire alarm signaling system.
Fire Damper
Device that automatically restricts the flow of air through all or part of an air-handling system; usually activated by the building’s fire alarm signaling system or fusible links.
Exhaust System
Ventilation system designed to remove stale air, smoke, vapors, or other airborne containments from an area. See Heating, Ventilating, and Air Conditioning (HVAC) System.
Forced Air System
A building heating and cooling system that uses air as the heat transfer medium.
Hydronic System
A building heating and cooling system that uses water as the heat transfer medium.
Cooling Tower
Rooftop or independent unit that ejects waste heat into the atmosphere to lower the temperature in a system. Commonly used in HVAC systems.
Recirculation
Movement of air back into a ventilation system after being ejected.
Hurricane Glazing
Protective treatment for exterior windows designed to withstand hurricane conditions including high wind and impact.
Smoke Control
Strategic use of passive and active devices and systems to direct or stop the movement of smoke and other products of combustion.
Smoke Control Mode
Setting on an HVAC system or Fire Alarm Control Unit system that can be activated automatically or manually to initiate a programmed smoke control procedure.
Firefighter’s Smoke Control Station (FSCS)
Interface between the smoke management system and the fire response forces.
Draft Curtains
Noncombustible barriers or dividers hung from the ceiling in large open areas that are designed to minimize the mushrooming effect of heat and smoke and impede the flow of heat. Also known as Curtain Boards and Draft Stops.
Smoke Tower
Fully enclosed escape stairway that exits directly onto a public way; these enclosures are either mechanically pressurized or they require the user to exit the building onto an outside balcony before entering the stairway. Also known as Smokeproof Enclosure or Smokeproof Stairway.
Single-Injection System
Stairwell pressurization system that uses on point of supply air; pressurization can be lost if the system becomes unsealed through the use of doors.
Multiple-Injection System
Stairwell pressurization system that uses an air supply shaft that discharges supply air at a uniform rate along several points within the stairwell.
Compensated System
Stairwell pressurization system that can modulate the pressure in the stairwell in relation to the interior of the building, or vent excess pressure.
Overpressure
Air pressure above normal or atmospheric pressure.
Transformer
Device that uses coils and magnetic fields to increase (step-up) or decrease (step-down) incoming voltages.
Arc
High-temperature luminous electric discharge across a gap or through a medium such as charred insulation.
Dielectric
Material that is a poor conductor of electricity, usually added to tools used to handle energized electrical wires or equipment.
Polychlorinated Biphenyl (PCB)
Toxic compound found in some older oil-filled electric transformers.
Generator
Device for generating auxiliary electrical power; generators are powered by gasoline or diesel engines and typically have 110- and /or 220- volt capacity outlets.
Stationary Storage Battery System
A system including a battery, a charger, and electrical equipment for a particular application. This type of system can include a lead-acid battery or a safer type of battery.
Buildings that are four or more stories in height may be
Required to include one stairway that extends to the roof for access to mechanical equipment, and is identified by signage in the stairway
Stairs with open sides must
Also include handrails and guards to prevent people or objects from falling onto adjacent spaces
Protected stairs must
Resist the effects of the products of combustion
Exterior stairs are naturally ventilated
On one or more sides
Passive smokeproof enclosures protect the stairway enclosures and provide a
Means of smoke ventilation before the smoke enters the stair enclosure
Building codes typically allow the use of open stairs in buildings only when
They connect no more than two adjacent floors above the basement level
On elevators with DC motors, the brakes
Do not play any part in actually stopping the elevator car. The motor stops the car and then the brakes are applied to hold the car in place
Terminal device
An electric switch that terminates power before the elevator reaches the upper or lower limits of the hoistway
Buffers
Large springs or hydraulic cylinders and pistons located at the bottom of the pit that acts as shock absorbers should the terminal switch fail. Buffers cannot safely stop a freefalling car; they only stop a car traveling at its normal rate of speed
Speed reducing switch
Also known as the speed governor. This switch slows the drive motor when an elevator starts to exceed a safe speed
Overspeed switch
Also connected to the speed governor. This switch is activated if the speed reducing switch fails to slow the car sufficiently
Elevator and stair shafts are built early in the construction process, and
Often use shear walls.
When used as a means of egress, an elevator shaft must be
Equipped with safety lights and fire ratings suitable to height of the structure
Rooftop smoke and heat vents are typically required Roofs of
Large area buildings and in buildings with a few windows including industrial, storage, and Mercantile buildings
The size and spacing of smoke and heat vents depends on
The floor to ceiling height of the building and the nature of the contents
The method used to determine the vent area requires
An analysis of the rate of heat release of the fuel, the ceiling height, and the depth of the curtain boards
