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.
Echo
A sound wave that has been reflected with sufficient magnitude and delay, so that it’s heard as a distinct sound separate from the directly transmitted sound.
Diffusion
The random distribution of sound from a surface that occurs when the surface dimension is equal to the wavelength of the sound striking it.
Diffraction
The bending of a sound wave around an object or through an opening.
Persistence
The result of multiple reflections in an enclosed space in a short period of time.
Noise criterion
This method consists of a set of criteria curves ranging from 63 to 8000 Hz and a tangency rating procedure. The criteria curves define the limits of octave band spectra that must not be exceeded to meet the occupants’ acceptance in the actual spaces.
Preferred noise criteria (PNC)
Preferred noise criteria (PNC) is a modification of NC curves that have sound pressure levels lower than the NC curves on the low/high-frequency needs of the chart.
Concert hall/recording studio NC: 15 dB to 20 dB.
Bedroom/hospital/large conference NC: 20 dB to 30 dB.
Private office/small conference/library NC: 30 dB to 35 dB.
Large office/retail/restaurant NC: 35 dB to 40 dB.
Lobby/open work space/laboratory NC: 40 dB to 45 dB.
Commercial kitchen/computer room/light maintenance shop NC: 45 dB to 55 dB.
Sound masking
A technique used to hide unwanted sounds by the addition of controlled sounds (aka, pink/white noise).
Speech privacy
Speech privacy is a function of the degree of sound isolation provided by the barriers between rooms and the ambient sound level in the receiving room. • Two measures used to evaluate open office acoustics are the articulation class and articulation index. • They are intended only for open office situations where speech is the primary sound concern.
Articulation class
Gives a rating of system component performance and does not account for masking sound.
Articulation index
The articulation index (AI) is a tool used to predict the amount of speech that is audible to a patient with a specific level of hearing loss. The AI figure for a given patient can range from zero to one, representing the proportion of the average speech signal that is audible.
Flutter
A buzzing or clicking sound that comprises repeated echoes traversing back and forth between two non-absorbing parallel surfaces.
• Either change the shape of the reflector or their parallel relationship or add absorption.
Electric locks
An electronic lock (or electric lock) is a locking device that operates by means of electric current. Electric locks may be connected to an access control system, the advantages of which include key control, where keys can be added and removed without rekeying the lock cylinder, and the ability to be remotely monitored and controlled, both for locking and unlocking.
CCTV
Video network for security. Video cameras are placed throughout a building and campus and wired to TV monitors in a central security location.
Card readers
A common electronic access control device. Systems can be programmed to control hours of use, monitor car use through logs, and remove access codes for a lost or stolen card.
Mechanical locks
A lock is any device that prevents access or use by requiring special knowledge or equipment. Mechanical locks are mechanical devices that secure an opening by keeping a door closed until a release mechanism is activated, usually a lever, knob, key, or thumb turn.
Electromagnetic locks
An electromagnetic lock, magnetic lock, or mag-lock is a locking device that consists of an electromagnet and an armature plate. There are two main types of electric locking devices : fail-safe and fail-secure. A fail-secure locking device remains locked when power is lost. Fail-safe locking devices are unlocked when de-energized. Direct pull electromagnetic locks are inherently fail-safe.
Hydraulic elevator
Travels inside a cylinder. An electric motor pumps hydraulic oil into the cylinder to move the piston. The piston smoothly lifts the elevator cab. Electrical valves control the release of the oil for a gentle descent.
Electric traction elevator
Geared and gearless traction elevators with machine room. Traction elevators are lifted by ropes that pass over a wheel attached to an electric motor above the elevator shaft. They are used for mid- and high-rise applications and have much higher travel speeds than hydraulic elevators.
Gearless traction elevator
These elevators typically operate at speeds greater than 500 feet per minute (2.54 meters per second). In a gearless traction machine, woven steel cables called hoisting ropes are attached to the top of the elevator car and wrapped around the drive sheave in special grooves.
Geared traction elevator
An electric motor in this design drives a gear-type reduction unit that turns the hoisting sheave. Although slower than a typical gearless elevator, the gear reduction offers the advantage of requiring a less powerful motor to turn the sheave. These elevators typically operate at speeds from 350 to 500 feet per minute (1.7 to 2.5 meters per second) and carry loads of up to 30,000 pounds (13,600 kgs).
Main brake
This is mounted on the shaft and operated by the control mechanism. The brake is self-applying, so the car will stop in the event of a power failure.
Governor
This measures and limits elevator speed by means of the control panel. It will actuate the safety rail clamp if the elevator tries to exceed its proper rate of travel.
Safety rail clamps
These grip the side of the rails if there is an emergency.
Car bumpers
Located on the bottom of the car, they stop the car if it over travels at low speed.
Interlocks
These prevent the elevator from operating unless the hoistway door is closed and locked.
Proximity dictators
Similar to safety edges, but they sense the presence of a person near the door and can stop the closing motion.
The cabs will self-level to reduce tripping hazards.
Smoke control
This standard protects life and reduces property loss by establishing requirements for the design, installation, and testing of smoke control systems used to mitigate the impact of smoke from fire.
Containment
To confine a fire to the zone of origin for a specified time, thereby preventing fire spread and leaving more time for safe evacuation of the building occupants. Specially engineered containment systems are used as enclosures in instances where specific identifiable hazards within a building need to be independently isolated from the remainder of the building.
Firestopping
Firestopping is an integral part of fire protection engineering. Firestop systems protect against the passage of flames, deadly gases, and toxic smoke through openings that are created for penetrations, joints, and gaps in fire-resistive walls, floors, and floor/ceiling assemblies. The integrity of fire-rated assemblies is restored by firestop systems.
Passive fire protection (PFP)
Passive fire protection (PFP) is a group of systems that compartmentalize a building through the use of fire-resistance-rated walls/floors. Compartmentalizing your building into smaller sections helps to slow or prevent the spread of fire/smoke from one room to the next.
Active fire protection (AFP)
Active fire protection (AFP) is a group of systems that require some amount of action or motion to work efficiently in the event of a fire. Actions may be manually operated, such as with a fire extinguisher, or automatic, such as by a sprinkler; but, either way, they require some amount of action. AFP includes fire/smoke alarm systems, sprinkler systems, and fire extinguishers, as well as firefighters.
Ball drip
Automatic drain valve at the bottom of a dry standpipe; used to ensure the standpipe remains dry.
Siamese connection
Provided outside a building for fire department hose connection.
Halon extinguisher
Used when water damage might be bad for the room (e.g., computer rooms).
Foam extinguisher
Used where flammable liquid fires might occur (e.g., industrial buildings, aircraft hangars).
Intumescent paint
A material that expands rapidly when exposed to heat, insulating the surface.
Ionization detectors
Gaseous ionization detectors are radiation detection instruments used in particle physics to detect the presence of ionizing particles and in radiation protection applications to measure ionizing radiation.
Cavity resonators (Helmholtz)
A large air space that is filled with absorptive material and a small-sized opening to absorb specific low-frequency ranges.
Reverberation time (RT)
Clear echo is caused when reflected sound of a sufficient intensity reaches a listener more than 50 ms after he or she has heard the direct sound.
Sound power
The rate at which sound energy is emitted, reflected, transmitted, or received per unit time. The SI unit of sound power is the Watt (W).
Clerestory
A row of upper windows in a wall above a roof to let light deeper into a space.
Fire compartmentation
A vital part of passive fire safety design, it is composed of special floor, ceiling, and wall assemblies as a means to confine fire, heat, smoke, and toxic gases. It can provide a safe area of refuge for occupants and firefighters.
Roof monitor
Concealed space
When is a fire pump needed?
When the municipal water pressure is not high enough, the pump provides the added water pressure required for fire protection systems. Fire pump rooms should be sprinkled and protected with a one-hour fire rating. Additionally, emergency lighting and ventilation should be provided.
NFPA 13, NFPA 13D, NFPA 13R
TNFPA 13 is the standard for design and installation of sprinkler systems. NFPA 13D (one- and two-family dwellings) and NFPA 13R (up to and including four-story residential) are subsets of NFPA 13.
List the differences between sound absorption and sound insulation.
Sound absorption is dependent on the physical properties of a material, space, or object and on the sound source. The energy of the sound is absorbed and dissipated before being transmitted. It is utilized to stop echoing in a space (e.g., fiberglass, carpeting).Sound insulation is dependent on the sound-insulating qualities of the materials being used. It is utilized to stop sound from traveling to adjacent spaces. It reduces sound transmission but cannot prevent it (e.g., gypsum, CMU block).
Concealed space
Concealed spaces in buildings allow fires to spread undetected. Fire blocking and draftstopping are required to prevent fire from spreading into concealed spaces.
