OBJ 3.3 Flashcards
Sally port
A sally port is a secure, enclosed entryway to a prison or holding facility.
Bollards
Bollards are short, sturdy vertical posts. They are used as security devices to keep vehicles away from plazas and buildings.
Elevator types
Hydraulic: Most appropriate for low-rise buildings, hydraulic elevators are usually slower and have a maximum travel distance of 50 to 60 feet. They use hydraulic pistons to push the elevator car from below.
Traction (geared and gearless): Most appropriate for mid-rise and high-rise buildings, traction elevators use cables and counterweights to move the elevator car. The cable is attached to a motor at the top of the elevator shaft that moves the car up and down while using the counterweight to make the process more efficient.
Machine room-less: Both hydraulic and traction elevators typically require a machine room to house the main motor, but recent advances in elevator technology allow both types to function without the requirement of a machine room.
MDF and IDF
Main distribution frame (MDF): A distribution frame that connects and manages communication between IDF rooms within the building and external public lines coming into the building.
Intermediate distribution frame (IDF): A distribution frame that connects individual workstations with the MDF.
Borrowed light
A window inside a building in a partition between a room that doesn’t have windows and one that does, so that the interior room can “borrow” light from the latter.
Inventor of the modern elevator
Elisha Otis is credited with inventing the modern elevator when, in 1854, he showcased his invention of a safety brake, making elevator travel much safer.
Inverse square law
The concept that, in a free field, the intensity of sound drops by 6 dB for every doubling of distance from the source of sound.
Sound transmission class
Is an integer rating of how well a building partition attenuates airborne sound. Higher STC ratings equate to better noise attenuation.
Deluge system
Fire sprinkler system in which sprinkler heads are always open. When activated by a sensor, all sprinkler heads activate at once. Used in high-hazard areas where flooding could be required to control a fire.
Dry standpipe system
Fire sprinkler system in which pipes are fixed in the building and filled with compressed air. They are not filled with water until needed (by the fire department), which makes this a good system for areas subject to freezing.
Wet standpipe system
Fire sprinkler system in which pipes are always filled with water and pressurized at all times. They are the most common system, with a low initial cost and a quick response time, but they are susceptible to freezing.
Coaxial cable (coax)
Cable commonly used by cable operators, telephone companies, and internet providers to convey data, video, and voice communications.
Cat-5 cable
Cable commonly used to connect and create local computer networks (aka, Ethernet cable).
Magnetic lock (mag-lock)
An electromagnetic door locking mechanism that is created by a current moving through a wire. If the current is disrupted, the metal wire is no longer magnetized and the lock will no longer function as a security method. It can be hooked up to fire alarms, card readers, or other trigger points to turn the current on or off and control the door.
Hold open
Door hardware meant to hold a door in the open position. Can be manual (loop and hook), magnetic (opposite magnets on wall and door), or electromagnetic (charged wire). If electromagnetic, it can be linked to a fire alarm to automatically close.
Electric strike
An electromagnetic door locking device created by a low-voltage current and used with various locksets. If the current is disrupted by a card reader or other trigger, the door is allowed to open. If the current is engaged, the door will remain locked.
Closer
A mechanical device that closes a door after someone opens it or after it was automatically opened. Typically mounted on the top of a door and to the doorframe.
NFPA
National Fire Protection Association.
Notable building fires
Great Chicago Fire, 1871.
Triangle Shirtwaist Factory, New York, 1911.
Hartford Hospital, Connecticut, 1961.
Beverly Hills Supper Club, 1977.
MGM Grand, Las Vegas, 1980.
The Station nightclub , Rhode Island, 2003.
Grenfell Tower, London, 2017.
FDC
Fire department connection. Located on the outside of the building, the fire department connection is where firemen can hook their hoses up to the sprinkler or standpipe system to supplement the water supply. The FDC is composed of an inlet, which is the part that you see, a check valve, and piping.
Types of fire engines/trucks
Different types of firefighting apparatus are made to specialize in various fire and rescue operations. Ladder, pumper, and tanker trucks are the three main types that service building fire and rescue operations.
Fire command station
A room in a high-rise building that contains communications equipment that the fire department uses to coordinate its team in the event of a fire. The command center is usually on the first floor and is easy to find. This room contains graphic annunciator panels that indicate where fires have been detected, where sprinkler systems have been activated, and other important information.
Notable structure collapses
Tacoma Narrows Bridge due to wind gusts, Washington State, 1940. Hartford Arena, roof collapse due to snow, Hartford, Connecticut, 1978. Kansas City Hyatt Regency Hotel atrium walkway collapse due to a faulty connection detail of a hanger rod to a box beam support, Kansas City, Missouri, 1980.
Horizontal assembly
In fire-resistant construction, a horizontal assembly is a roof or floor assembly designed to restrict the spread of fire.
M, S, N, O
M, S, N, and O are the four basic types of mortar. M is the strongest mortar, followed by S, N, and then O. M is used in brick, concrete block, and stone masonry construction; it can be used on or below grade for foundation walls, retaining walls, and pavement. S contains two parts portland cement, one part lime, and nine parts sand; it can be used on or below grade for foundation walls, retaining walls, and pavement. N is general purpose mortar; it can be used above grade in both exterior and interior load-bearing installations, often with soft stone masonry. O is used in both exterior and interior non-load-bearing installations.
Sabin
A unit of sound absorption. One square foot of 100 percent absorbing material = 1 sabin. Used for calculating the reverberation time of theaters, concert halls, recording studios, etc.
Acoustical absorption A (sabins)
(Total surface area of barrier or component between rooms, S) x (coefficient of absorption, a ).
Noise reduction coefficient
(Total sabins, sound absorbing units, A) / (total surface area in the room, S).
Resonance
The tendency of a system to vibrate at increasing amplitude at certain frequencies.
Reverberation
The persistence of sound after a sound is produced. A reverberation, or reverb, is created when a sound or signal is reflected, causing a large number of reflections to build up and then decay as the sound is absorbed by the surfaces of objects in the space, which could include furniture, people, and air.
