Chapter 4 Flashcards
Building codes have traditionally required a minimum of one___for stair serving buildings five stories or higher
Smoke proof stair enclosure
More recently codes also require protection for stairs serving floor levels MORE THAN___below the level of exit discharge
30 feet
This type of smoke proof enclosure protects the stairway enclosure and provides a means of smoke ventilation before the smoke enters the stair enclosure
Passive
These vestibules are also pressurized to assist in keeping smoke out of the stairway
Active smoke proof and closure
These enclosures are accessed through a vestibule or an exterior balcony
Passive smoke proof 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
The stairs are naturally ventilated on one or more sides
Exterior stairs
Stairs that are not part of the means of egress are often referred to as?
Convenience
Buildings that are _______ in height may be required to include one stairway that extends to the roof for access to mechanical equipment and as identified by signage in the stairway
4 or more
A primary safety hazard at conveyor penetrations during a fire
Incomplete door or shut or closure
Passenger elevators design to also carry freight
Service elevators
Elevators that carry people
Passenger elevators
Elevators Carry resources that may be bulky or heavy
Freight elevators
These elevators do not have brakes
Hydraulic elevators
Historically, the practical upper limit for hydraulic elevators was about?
6 stories
This elevator style is intended for cargo use
Dumbwaiter
For Carmen styles of elevators are:
Drum elevators. Traction elevators. Machine room less elevators. Dumb waiters.
These elevators are obsolete and only found in very old structures or in use as freight elevators
Drum
These elevators are the most common type of elevator in buildings over six stories
Traction
Electrical circuit and watch the current can move through the circuit in both directions and the flow can be constantly reversing
Alternating current
Electrical circuit in which the current moves through the circuit in only One Direction
Direct current
The brakes do not play any part in actually stopping the elevator car. The motor stops the car and then brakes are applied to hold the car in place
Elevators with DC motors
These elevators historically were drawn with ropes and used to move food from the kitchen to upper floors and occupancy is including: restaurants, schools, hospitals, retirement homes
Dumbwaiters
Tapered pairs of steel jaws that wedge against the guard rail‘s and bring the elevator to a stop. These are designed to stop a freefalling car
Elevator safeties
If the car continues to accelerate, the switch trips the over speed switch and applies the car safeties
Speed reducing switch
Elevator hoistway enclosures usually are required to be a fire rated assembly with_hour rating, depending on the height of the building
One or two hour rating
Elevator hoistwsy:
In a low rise buildings, the entire hoistway enclosure may consist of?
Gypsum, cement block, or other easily penetrating material
HVAC-
DUCT DETECTORS Are typically provided for fans with capacities_____to stop these systems under fire conditions and minimize unwanted smoke commitment
Exceeding 2000 ft.³ per minute
HVAC-
Codes regulate the location of air intakes to minimize drawing in the following hazards:
Combustible, flammable or toxic substances. Vehicle exhaust. Smoke from fires a nearby structures
HVAC-
The cooling equipment hazards are limited mainly to hazard associated with the?
Refrigerant and the electrical equipment
The distribution component of the HVAC system
Air ducks
Unoccupied space within the building through which air flows back to the heating ventilation and air-conditioning system. Normally immediately above the ceiling and below an insulated roof or the floor above
Return air Plenum
Device that automatically restrict the flow of smoke through all or part of an air handling system; usually activated by the buildings fire alarm signaling system
Smoke damper
Device that automatically restrict the flow of air through all or part of an air handling system; usually activated by the buildings fire alarm signal in the system or fusible links
Fire damper
Ventilation system designed to remove stale air, smoke, vapors, or other airborne contaminants from an area.
Exhaust system
A building heating and cooling system that uses air as the heat transfer medium
Forced air system
Many HVAC systems distribute conditioned air through the building from one or more mechanical equipment rooms via ductwork. Such systems are generally known as?
Forced air systems
Strategic use of passive and active devices in systems to direct or stop the movement of smoke and other products of combustion
Smoke control
The following systems can signal HVAC controls to transfer to smoke control mode:
Smoke detectors. He detectors. Sprinkler water flow switches.
“Automatic smoke control”
Smoke control systems-when a system has both automatic and manual capability,___shall take priority over___
Manual operation shall take priority over the automatic control
These hatchways often open a minimum of 4 feet in either direction
Heat and smoke events
Non-combustible barriers or dividers hung from the ceiling in large open areas that are designed to minimize the mushrooming affect of heat and smoke and impede the flow of heat. Also known as curtain boards in draft stops
Draft curtains
Roof vents in a sprinkler building may be of maximum value in removing products of combustion during the ?
Final or over hall stages of a fire
Fully enclosed escape stairway the exit is directly onto a public way
Smoke tower
One style of smoke control for stairways is the use of a___separated from a building Corredor by a vestibule that is open to the atmosphere
Smoke tower
In a___, the airflow into the stairwell can be adjusted depending on the number of doors that may open
Compensated system
Electrical equipment: high-voltage equipment is defined as operating at?
600 V or higher
Low-voltage equipment operator?
Less than 600 V
Device that uses coils and magnetic fields to increase step up or decrease step down in coming voltages
Transformers
Most modern dry transformers are designed for use inside?
Sprinkler spaces
Transformers containing PCBs are required to?
Be labeled
Material that is poor conductor of electricity, usually added to tools used to handle energized electrical wires or equipment
Dielectric
High temperature luminous electric discharge across a gap or through a medium such as charred insulation
Arc
Toxic compounds found in some older oil filled electric transformers
Polychlorinated biphenyls
