Skip to main content

Critical Technologies Acronym List

AbbreviationEllaborationDescription
AHUAir Handling UnitAn AHU conditions and distributes air through a building, but its main purpose is the distribution. It takes air from the outside and combines it with return air from the building. It then goes through a filter, then moves over heating/cooling coils to achieve the desired temperature (possibly dehumidifiers/humidifiers as well), then a fan is used to blow the air and circulate the new conditioned air throughout the building. There are dampers found in the AHU which act as valves regulating the amount of air flow going through the unit.
ASIArchitect’s Supplemental InformationAn ASI is a formal document issued by an architect to clarify, correct, or add information to the construction drawings or specifications after the contract is signed. It is not an updated version of the construction document; it is just a supplemental document that adds information.
ATSAutomatic Transfer SwitchAn electrical switch that switches load between two sources when it senses an issue with the primary power source. Usually from a main power source to a backup power source, like a generator.
AVAudio & Visual Systems in conference roomsIt typically involves devices like microphones, speakers, amplifiers, projectors, displays, cameras, and control systems, working together to manage and deliver content to an audience. For a conference room, there are usually just microphones, speakers, amplifiers, cameras, and TVs/monitors.
BASBuilding Automation SystemIt is a computer-based system that controls, monitors, and regulates the HVAC and mechanical systems of a building without the need for direct physical human intervention. It can also include security and monitoring systems.
BDFBuilding Distribution FrameAlso referred to as the Main Distribution Frame, or Mainframe, it is a central termination point for building network and telecommunication cables in a building.
BIMBuilding Intelligence ModelA BIM is a digital representation of a building that integrates various data points about its physical and functional characteristics to optimize performance, enhance user experience, and improve operational efficiency. This would be the UI friendly EC-Net-4 component models that can be monitored and controlled from a computer.
BMSBuilding Management SystemA computer-based control system that monitors a building’s mechanical and electrical equipment. The management system encompasses all the building’s systems, including the automation system. The BAS is a component that helps to manage the systems in the building, but not all the systems.
BODBasis of DesignThe "Basis of Design" (BOD) is a document that outlines the fundamental decisions and assumptions made during the design process, ensuring alignment with the Owner's Project Requirements (OPR) and relevant standards. It gives justification to the design and gives construction workers a more comprehensive understanding of what the product should be.
BOMBill of MaterialsA list of the raw materials, assemblies, components, parts, and quantities needed to manufacture a product.
BPBooster PumpIncreases the water pressure, supplemental to the primary pump, in a building’s water system.
BuswayPrefabricated electrical distribution system consisting of bus bars in a protective enclosure, providing power distribution through tap boxes. They look like I-beams, and they are usually suspended from the ceiling.
Bus BarsTerminals at the end of the busway, they are flat bars. They are an alternate solution to traditional wiring and conduit.
CBCircuit BreakerSwitch that automatically opens the circuit loop if the circuit is overloaded or shorted.
CCDConstruction Change DirectiveA CCD is a written order from the owner or architect to a contractor, instructing them to perform work that deviates from the original contract, even if they haven't agreed on the cost or schedule adjustments yet.
CDConstruction DocumentsA construction document is usually an architectural drawing. These drawings visually communicate the design intent, spatial relationships, and technical requirements of a building project. They include floor plans, elevations, sections, and details that guide the construction process.
CIBTCable Infrastructure Build TeamA CIBT is a group of professionals responsible for the design, installation, maintenance, and repair of the physical network that connects devices, servers, and other hardware within a building or across different locations. This is partially HBT’s team’s responsibilities.
COChange OrderA change order is a written document that modifies an existing contract, typically in construction or public improvement projects. It outlines changes to the scope of work, schedule, or cost of the original agreement. It is important to note that these are not just requests, but formal amendments.
CORChange Order RequestCOR is the same as a CO (Change Order), except it is a request.
CPPCam Lock Power PanelA camlock power panel is a specialized electrical panel that uses camlock connectors for temporary power distribution. These panels specialize in temporary power distribution and temperature-controlled environments.
CMConstruction ManagerEnsures a project is completed safely and within budget.
ContainmentPhysical containment of either hot or cold air, to be supplemented with the building's cooling to create the working conditions for a data center. Facebook's typical DC builds use hot aisle containment, while our colo facilities can vary. If you're in London, con-tainment means structured cable tray.
CSWCore SwitchA core switch is a high-capacity network switch positioned at the "core" or backbone of a network, responsible for high-speed data transfer and connectivity between different parts of the network. Acts as a central hub.
Cold StorageBack-up storage of data, not to be retrieved on an ongoing basis. Typically Tape or Spin-Down Drive storage.
ColoCo-location facility; leased suites in an independently owned data center.
CRACComputer Room Air ConditionerThis is responsible for the bulk of the conditioning, which cools the air. The unit is also usually outside.
CRAHComputer Room Air HandlerThis is responsible for moving the air throughout the room and is usually indoors. It may do some cooling or heating, but this is only to maintain the desired temperature.
CPMCritical Path MethodIt is the sequence of events or tasks that directly affect the duration of the project. It is a method that ensures the movement of materials and schedules are related to the CPM path and makes the project timeline as efficient as possible.
CSWCluster SwitchA cluster switch, in the context of networking, refers to a group of switches that are managed as a single logical unit. This allows for simplified management, increased bandwidth, and redundancy by combining multiple physical switches into a virtualized entity. 
CXCommissioningCommissioning is the verification that all components function as intended from the start and throughout the building's operation. 
CXACommissioning Authority/AgentThe official person who authorizes and approves the commissioning.
DCData CenterFacility used to house computer systems and associated components, such as telecommunications and storage systems.
DCCData Center Connectivity teamResponsible for managing and maintaining the network infrastructure that connects a data center to the outside world and to other data centers.
DCIMData Center Infrastructure ManagementSimilar to the connectivity team but is more responsible for the physical infrastructure of the servers, storage, power, cooling, and security.
DC UPSDirect Current Uninterruptible Power SupplyA DC power supply that is provided as backup to the primary power supply.
DDDesign DevelopmentProcess of completing a design.
DDCDirect Digital ControlDirect Digital Control (DDC) is a computerized control system that uses digital microprocessors to automate and manage processes, typically in building automation systems (BAS) like HVAC. Distech is the DDC software used at HBT.
DDCDry Dust CollectorA dry dust collector works by using a filter to separate dust and particles from the air, trapping the dust and releasing the cleaned air. It typically involves a blower to draw air into the system, a filter to capture dust, and a mechanism to remove the collected dust. 
DDFDDone Done Freaking DoneFinal revision of a document or deliverable.
DOASDedicated Outdoor Air SystemIt is a specialized HVAC system designed to introduce and condition 100% outside air into a building, independent of the main heating, ventilation, and air conditioning (HVAC) system. Although the unit is separate from the main HVAC system, they usually act in conjunction with one another.
DPDistribution PumpA pump that distributes fluid through a system. Assure consistent flow and pressure.
DXDirect ExpansionType of cooling unit used in data centers. This is where refrigerant directly cools the air or liquid being conditioned.
EC&HEvaporative Cooling and HumidificationIt uses the endothermic properties of water evaporation to cool and add water to the air.
End-Feed BoxPower Feeder Outlet Box delivering power from RPP (Remote Power Panel) or in-row UPS (Uninterruptible Power Supply) to Busway.
ETOEarly Turn Over, used in project management.It means turning a project over early from HBT to the client, or within HBT and it goes from one team to another.
EOREngineer of RecordIt is the licensed engineer on site who is responsible for the design and construction of a project.
Fac NetFacilities Network
FAT CATFacebook’s backbone network system for latency reduction.
Fiber CanPatch panel for fiber. Ethernet connection delivered by fiber cable.
FF&EFixed Furniture & Equipment
FLAFull Load AmperageIt is the maximum amplitude of amperage that the control panel can take based off the breakers. For example, if the highest amperage breaker and only breaker is 20A, then the FLA is 20A.
FPTFunctional Performance Test
FWTFactory Witness Test
GUIGraphical User Interface
GMPGuaranteed Maximum PriceDetermines the maximum price a client will pay for a project.
HMIHuman Machine InterfaceUsually a touch screen but can involve physical buttons with a screen too.
HMDHouse Mechanical DistributionIt refers to a house that people live in, not in-house.
HPMHighlights, People, MeWeekly Reports
HVBHigh Voltage BreakerBreaker for High Voltage
IBIssue BulletinIt’s a document or actual board that shows key issues, data to prove the problem exists, and solutions to the problem with people assigned to it.
IACIndirect Air CoolingOften uses a heat exchanger.
IBOSInfrastructure Business Operations Support
ICMInfrastructure Construction ManagementSame as IBOS but it is for construction management.
IDFIntermediate Distribution FrameIt is a secondary distribution point in a network infrastructure, usually for large networks like campuses or big buildings with high demands.
IFOSIntegrated Facility Operations Support
ISTIntegrated System Testing
In-Row UPSUninterrupted Power SupplyThe use of computers, storage, networking and other physical devices.
Jay BoxA server capable of switching load sources with internal failure.
KPIKey Performance IndicatorA measurable value that demonstrates how effectively an organization is achieving its objectives.
KVAKilovolt-AmpereA unit of measurement for electrical power.
LBSBLoad Bank Switch BoardCabinet size and takes high voltage around 800V AC.
LCPLocal Control PanelA panel that controls a specific area of the building.
LVLow Voltage120V AC or less.
LVSGLow Voltage Switchgear120V AC or less.
MAC AddressMedia Access Control AddressA unique hardware identifier assigned to a network interface controller (NIC).
MDFMain Distribution FrameThe main distribution point in a network infrastructure, usually for large networks.
MOABMotor Operated Air BreakerSwitch allows change between two power sources. Usually used for high voltage disconnect switches so they can be operated remotely, they are breakers powered by motors and using air as the driving force.
MOPMethod of ProcedureA document that outlines the steps to be taken to complete a task or process.
MPOEMain Point of EntryThe point at which the electrical power enters the Data Halls.
MSBMain SwitchboardThe main electrical distribution point in a data center (Low Voltage Applications).
MSGMain SwitchgearThe main electrical distribution point in a data center (High Voltage Applications).
MVAMega Volt-AmpereA unit of measurement for electrical power.
MVSMedium Voltage Switch
MVSGMedium Voltage Switchgear
MVPSSMedium Voltage Primary Selector Switch
MWMegaWattA unit of measurement for electrical power.
NOCNetwork Operations CenterA centralized location for monitoring and managing a network.
OACOwner Architect ContractorThe three parties involved in a construction project (Funder, Designer, Builder).
ODFOptical Distribution FrameA frame used to distribute fiber optic cables.
OFCIOwner Furnished Contractor InstalledThe owner provides the equipment and the contractor installs it.
OFEOwner Furnished EquipmentThe owner provides the equipment.
P6Primavera Scheduling SoftwareA project management software by Oracle.
Patch PanelA panel that connects multiple cables together.
PDUPower Distribution UnitA device that distributes power from a single source to multiple outlets.
PLCProgrammable Logic ControllerA computer that controls and monitors industrial processes.
PlenumA space in a building that is used for air circulation.
Plug-In BoxConnects racks and DC UPSs (Direct Currect Uninterrupted Power Supply) to the main power distribution system.
POCPoint of ContactA person or team responsible for a specific task or project.
POPPoint of PresenceA location where a network or service provider has a physical presence.
PORPlan of RecordThe final approved plan for a project.
PQMPower Quality MeterMeasures the quality of the power supplied to a load.
PRPurchase RequestA document that outlines the requirements for a purchase.
PTXPower TransformerA device that transforms electrical power from one voltage to another.
RCMRegional Construction ManagerThe person in charge of construction projects in a specific region.
RDDCRapid Deployment Data CenterA data center that can be quickly deployed and set up.
RFIRequest for InformationA document that requests information from a vendor or supplier.
RFPRequest for ProposalA document that requests proposals from vendors or suppliers.
RHRelative HumidityThe amount of moisture in the air.
ROReverse OsmosisA process that removes impurities from water that uses a semi-permeable membrane to remove contaminants from water by applying pressure.
RPPRemote Power PanelA panel that controls and distributes power remotely.
RSWRack SwitchA switch that is mounted in a rack.
RTURooftop UnitA type of air conditioning unit that is mounted on a roof.
SAISystem Acceptance InspectionAn inspection that verifies that a system meets the requirements of the project.
SBSwitchboardA panel that controls and distributes power.
SBDCStick Built Data CenterA data center that is built using traditional construction methods.
SCOSupply Chain OperationsThe management of the flow of goods, services, and related information from raw materials to end customers .
SDSchematic DesignThe design phase of a project where the overall layout and design of the building is created.
SE&DStrategic Engineering and DevelopmentThe process of developing and implementing a strategic plan for a project.
SF6 BreakerSulfur Hexafluoride BreakerA type of circuit breaker that uses sulfur hex to extinguish dangerous arcs. Used in high voltage circuits.
SOCSecurity Operations CenterA centralized location for monitoring and managing security systems.
SOESourcing and Operations EngineeringThe process of developing and implementing a plan for sourcing and operating a project.
Spine Down DriveSecondary storage device that is used to store data in a data center. It can be powered down when not actively in use, saving energy.
SOOSequence of OperationsA document that outlines the steps to be taken to complete a task or process.
SOPStandard Operating ProcedureA document that outlines the standard procedures for a task or process.
SOWStatement of WorkA document that outlines the scope of work for a project.
SP&AStrategic Planning and AnalysisThe process of developing and implementing a strategic plan for a project.
SPOCSingle Point of ContactA person or team responsible for a specific task or project.
SSWSpine SwitchThey do not connect directly to end devices, but they connect directly to leaf switches. They are responsible for controlling high speed data transmission to allow reliable communication across the network.
STCSystem Transfer CabinetA housing that holds & controls the switch's primary and backup power sources.
TABTest and BalanceThe process of testing and balancing a system to ensure it meets the requirements of the project.
Tap BoxPower Feeder Outlet Box with circuit breaker.
Tape DriveData storage device that uses magnetic tape to store data.
Target PlateGrate to disperse airflow in data halls.
TBHTo Be HiredA person who has been hired but has not yet started working.
TFTransfer FanA fan that is used to transfer air from one location to another.
TOR SwitchTop of Rack SwitchA switch that is mounted in a rack and is used to connect devices.
TPMTotal Program ManagementThe Facebook Infrastructure Technical Program Management Team
Ts & CsTerms and ConditionsThe terms and conditions of a contract or agreement.
UDBUser DatabaseA database that stores user information.
Uni-StrutMetal Framing SystemA system used to support and organize cabling and other equipment in a data center.
UPSUninterruptible Power SupplyA device that provides a backup power source.
UVUltravioletA type of electromagnetic radiation with a wavelength shorter than that of visible light.
VAVVariable Air Volume BoxA device that controls the amount of air that is supplied to a space. This controls the airflow in ducts by actuating a plate/damper to restrict air flow. They usually have conditioning heating/cooling coils.
VFDVariable Frequency DriveA device that controls the speed of a pump by adjusting the frequency input of the electrical power.
VRFVariable Refrigerant FlowA type of air conditioning system that uses a variable refrigerant flow to control.
Wet MediaWet media refers to evaporative cooling media or humidification media that is saturated with water. Air is passed through this wet media, and as the water evaporates, it absorbs heat from the air, resulting in a cooling effect and increased humidity. This is due to the latent heat of vaporization, where water changing to a gas state of matter undergoes an endothermic process, resulting in the absorption of large amounts of heat.
RHCReheat CoilA coil that is made to use electricity, water, or steam for the heating element.
ESPEthernet Switch PanelA control panel responsibile for organizing the communcation cables of a controllers that are dispersed in the building.
FMFlowmeterA device that measures the flow rate of a fluid.
PTPressure TransducerA device that measures the pressure of a fluid. It uses a diaphragm, which bends when pressure exerts a force on it, which causes an electrical signal.
TTTemperature TransmitterAn electronic device that converts the signal from a temperature sensor (thermocouple/thermistor) into an electrical signal for digital data.
CACompressed AirCompressed air is used to power pneumatic tools and equipment.
DCADry Compressed AirCompressed air that has been dried to remove moisture.
TSTemperature SensorA device that measures the temperature of a fluid.
TT&MTTemperature Transmitter & Humidity SensorSimilar to TT, except there is also a sensor that measures humidity.
WDCWet Dust CollectorA device that works by passing air through mist or moist air, then turns the dust into sludge which forms on the walls and then gets discarded.
PCWPProcess Chilled Water PumpA pump that circulates chilled water that is used to cool a process, like a condenser, boiler, or heat exchanger. This water is not filtered and is not safe for consumption or plumbing.
SPCSpaceThis is a term used to refer to the air or area surrounding the duct. This could be a room, or ceiling.
DPTDifferential Pressure TransmitterThis transmits an electrical signal of two different pressures that can be combined to form a difference in pressure.
SnagProblem created by HBT.
ConstraintProblem created by subcontractor/someone else.
SATSupply Air TemperatureThe temperature of the air that is supplied to a component.
CoxCommissioningThe process of ensuring that a system is installed, tested, and functions as intended.
PTPPoint to Point CheckoutThe process of verifying the correct wiring and functionality of each individual input and output (I/O) point within a control panel. This must be done on every control panel to verify that all components, inputs, outputs, and controllers are sending the proper signals and receiving the required power.
L1Panel ReadinessThe process of verifying that a control panel is ready for use. This includes verifying that all components.
L2Pre and Post EnergizationThe process of verifying the ground and voltages.
L3Point to PointThe process of verifying the correct wiring and functionality of each individual input and output (I/O) point within a control panel.
L4Final System CheckoutThe process of verifying that the system is functioning as intended, including graphics, red-line drawings, and program functionality.
CPControl PanelA panel that contains the controls for a system.
SPSub PanelA panel that contains the controls for a sub-system.
Host IDThe unique identifier for software licensing.
IP AddressAddress enabling communication between network devices.
ServerCentral Resource Manager in a Network
NetworkSystem of interconnected devices
HostDevice connected to the intenret.
ClientPersonal use device connected to the internet.
RouterDevice routing information packets across a network.

Revision History

RevisionDateNameDescription
1.0.08/5/2024Charlie DowInitial implementation
1.1.08/6/2024Greg DolceAdded terms
1.1.18/8/2025Sneha KarnikUpdated the Acronym List and added more terms.