NICET FAS-II key terms

The wiring path that carries alarm or supervisory signals from automatic detectors and manual pull stations to the fire alarm control unit. It may serve a conventional zone or a group of addressable devices.

The circuit that supplies operating power from the control unit to audible and visible signaling appliances such as horns, speakers, and strobes, and that the panel monitors for wiring faults.

A detector, module, or appliance on a signaling line circuit that carries its own unique address, so the control unit can report its exact location and status.

A supervised circuit that carries digital data between the control unit and addressable devices, letting many devices share a single wiring path while each is identified separately.

A group of initiating devices wired on one circuit that the control unit reports as a single area, without identifying which individual device operated.

The main panel that receives signals from initiating devices, applies its programmed logic, and activates notification appliances, relays, and off-premises transmitters.

A device that senses sustained water movement in a sprinkler or standpipe pipe and sends an alarm signal, usually after a delay that ignores pressure surges.

A device that monitors whether a control valve is fully open and sends a supervisory signal when the valve is closed or partly closed, indicating reduced protection.

A detector installed on or in an air-handling duct that samples the airstream for smoke; on alarm it typically stops the fan and signals the control unit.

A signal showing that a system or protected condition is impaired but no fire exists, such as a closed valve, low sprinkler air pressure, or a detector switched off.

A signal reporting a fault in the fire alarm system itself, such as an open circuit, a ground fault, loss of primary power, or a failed battery.

The standard audible evacuation pattern used in the United States: three half-second pulses, a pause, three more pulses, repeated, to signal occupants to leave.

A manually operated initiating device, mounted at a marked and accessible location, that lets a person send an alarm signal to the control unit.

A heat detector that responds when the temperature climbs faster than a set rate, catching fast-growing fires before a fixed temperature threshold is reached.

A facility, staffed or automated, that receives signals from protected premises, notifies the fire department, and documents the actions taken.

The official or agency with legal authority to review plans, issue permits, conduct inspections, and enforce fire code requirements within a jurisdiction.

The National Fire Alarm and Signaling Code, which sets requirements for designing, installing, testing, inspecting, and maintaining fire detection and signaling systems.

The National Electrical Code article governing fire alarm system wiring methods, including power-limited circuit classification, conductor requirements, and installation rules.

The maximum permitted distance between detectors, or between a detector and a wall or obstruction, set by code for the ceiling type and the detector listing.

A written description of how the system reacts to each input: which devices respond, what outputs activate, and in what order. It is used to program and test the panel.

A document signed by the installer and owner at system turnover that lists the installed equipment and its configuration and confirms installation matched the approved plans.

Drawings updated to show how the system was actually installed, including device locations, circuit routing, and field changes, kept for future service and inspections.

A design in which two or more detectors or zones must be in alarm before the system treats the condition as a real alarm or releases a suppression system.

A feature that resets a detector briefly after its first alarm and requires a second alarm within a set time before the signal is processed, reducing nuisance alarms.

A circuit whose wiring leaves the control unit and returns on a separate path, so it keeps operating with a single open or ground fault and uses no end-of-line resistor.

A circuit that does not return to the control unit, so a single open fault disables everything beyond it; an end-of-line resistor is used to supervise the wiring.

A circuit arranged so a single open or short does not stop operation; faulted sections are isolated so the rest of the signaling line circuit keeps working.

A resistor installed at the far end of a Class B circuit that lets the panel monitor the conductors for opens and shorts.

The normal branch circuit supplying AC power to the fire alarm system; it must be dedicated to the system, clearly labeled, and not controlled by a switch.

The standby source, usually rechargeable batteries or a generator, that keeps the system operating for a code-specified time when normal AC power is lost.

A design calculation adding standby and alarm currents to verify the battery can carry the system through the required standby period plus a full alarm period.

A check performed during design to confirm enough voltage reaches the last appliance on each notification circuit so all devices operate within their listed range.

A classification describing how well circuit wiring resists fire damage, ranging from no added protection to a two-hour rated enclosure, required for voice and other critical circuits.

An unintended connection between a circuit conductor and ground that can keep a circuit from working properly; the panel must detect and annunciate it.

The functional test performed after installation, before the system is placed in service, showing every device and function works as designed; results are documented for the AHJ.

The continuing program of periodic inspection, functional testing, and servicing required to keep a fire alarm system reliable after it has been accepted.

A test, often using a calibrated instrument, confirming that each smoke detector responds within the sensitivity range listed on its nameplate and in the design documents.