Engineer Building Facilities key terms

A factory-built or field-assembled cabinet containing coils, filters, dampers, and one or more fans that conditions and distributes air through ductwork to the spaces it serves.

A refrigeration machine that removes heat from water or another secondary fluid and rejects it at a condenser, supplying chilled water to air handling units and terminal cooling equipment in a building.

An open heat-rejection device that evaporates part of the circulating water to release condenser heat to the atmosphere; it serves chillers and process loads and needs water treatment and drift control.

A terminal unit with a damper that varies supply airflow to a zone in response to thermostat demand, often paired with a reheat coil, while the central fan maintains duct static pressure.

A control strategy that admits outdoor air for free cooling when outdoor temperature or enthalpy is favorable, reducing mechanical cooling; it depends on linked damper actuators and verified changeover sensors.

A networked digital control system that monitors and commands HVAC, lighting, power, and other equipment using sensors, controllers, and schedules to hold setpoints and generate alarms and trend data.

An engine-driven alternator with automatic transfer switching that supplies essential loads such as egress lighting, fire pumps, elevators, and life-safety systems when normal utility power fails.

A battery or flywheel-backed power conditioner that carries critical loads without interruption during a utility outage or source transfer, bridging the gap until a generator accepts load.

An assembly of check valves and relief ports installed to stop reverse flow of contaminated water into the potable supply; it requires periodic testing by a certified tester and code recordkeeping.

The number of subordinates reporting directly to one supervisor; narrow spans suit complex or safety-critical work, while wide spans cut cost but demand stronger procedures and staff competence.

A written or electronic authorization describing a maintenance task, its location, priority, labor and material estimates, and completion record; it is the basic unit for tracking cost and backlog.

A measurable value chosen to show how well an operation meets a goal, such as work order completion rate, mean time to repair, energy use per square foot, or customer satisfaction.

A negotiated contract between an employer and a certified union that sets wages, hours, job classifications, seniority, discipline, and grievance procedures, and legally binds both parties.

A documented, time-limited process that states specific deficiencies, measurable expectations, support offered, and review dates for an employee whose work has fallen below standard.

A staffing measure in which one FTE equals one person working a standard full schedule; part-time and overtime hours are converted so workload can be compared across shifts and budgets.

A document issued by the buildings department certifying that a structure complies with approved plans and codes for its stated use and occupancy, required before the space may be legally occupied.

The continuous and unobstructed path from any point in a building to a public way, made up of exit access, the exit itself, and exit discharge.

The number of people a space is designed to hold, computed from code area factors or fixed seating; it sets egress width, required exits, and plumbing fixture counts.

A person certified by the fire department to implement a building's fire safety plan, train occupants and staff, run drills, and coordinate with responding firefighters during an incident.

A fire alarm function that automatically returns elevators to a designated landing, opens the doors, and parks them so occupants are not trapped and firefighters gain control.

A rated assembly inside ductwork that closes on heat to preserve the fire resistance of the wall or floor it penetrates; it must be inspected and tested on a documented cycle.

A written procedure and hardware system that isolates hazardous energy, applies locks and tags, and verifies zero energy before service, protecting workers from unexpected startup or stored energy release.

A New York City law setting carbon emission limits for buildings over 25,000 square feet, with annual reporting and penalties above the caps, driving retrofits and electrification.

Scheduled servicing performed on equipment at time or usage intervals to prevent failures, preserve warranties, and sustain efficiency; tasks are generated from each asset's maintenance plan.

Work that is necessary but postponed for budget or operational reasons; the accumulated backlog raises failure risk and energy cost and should be measured, prioritized, and funded.

A multi-year schedule of major repairs, replacements, and upgrades with cost estimates and funding sources, aligning budgets with asset condition assessments and long-term facility needs.

An internal request that starts procurement by identifying goods or services needed, quantity, justification, account code, and required date, subject to approval before a purchase order is issued.

A solicitation that states the problem, scope, and evaluation criteria and asks vendors to propose solutions and pricing; used when best value requires judgment beyond lowest bid.

A contract schedule defining measurable performance obligations such as response time, uptime, cleaning frequency, and remedies for shortfall, used to manage vendors and in-house expectations.

Software that holds the asset register and generates, assigns, and closes work orders while capturing labor, parts, and history data used for planning and budget analysis.

A cooling rate equal to 12,000 British thermal units per hour, roughly the heat needed to melt one ton of ice in a day; equipment capacity is commonly stated in tons.

A material's resistance to heat flow, expressed in square feet times degrees Fahrenheit hours per BTU; higher values mean better insulation, and assemblies add layer resistances in series.

Relations describing how fan or pump flow, head, and power change with speed: flow varies with speed, head with its square, and power with its cube, for geometrically similar machines.

The ratio of real power in kilowatts to apparent power in kilovolt-amperes; low values signal inefficiency and utility penalties, often corrected with capacitors or synchronous equipment.

The number of years for annual savings to repay an investment's initial cost, computed as cost divided by yearly savings; easy to communicate but blind to the time value of money.

The sum of a project's future cash flows discounted to today at a chosen rate, minus initial cost; a positive result means the investment earns more than the required return.

For repairable equipment, total operating time divided by the number of failures in that period; it estimates reliability and informs spare parts stocking and replacement planning.