NV Fire Alarm key terms

A remote display panel that shows the status of a fire alarm system, including alarm, supervisory, and trouble conditions, by zone or device, so responders can locate the source without going to the main control unit.

An initiating or notification device that carries a unique digital identifier on the signaling line circuit, letting the control unit report its exact location and status rather than only a general zone.

An audible or visible output produced by the system to warn occupants of a fire emergency, distinct from supervisory and trouble signals, and typically activated automatically by an initiating device or manually by a pull station.

A system architecture in which the control unit polls intelligent sensors for analog values such as smoke obscuration or temperature, then applies programmed thresholds and algorithms to decide whether an alarm condition exists.

A device such as a horn, bell, chime, or speaker that produces sound to alert occupants, evaluated for sound pressure level, temporal pattern, and audibility above ambient noise in the protected space.

The documented arithmetic proving secondary batteries can carry the system's standby load for the required duration plus the alarm load afterward, accounting for aging and voltage drop at end of discharge.

A remotely mounted power supply, often with its own battery, used to energize notification appliance circuits when the main control unit's output capacity or wiring distances cannot supply the required appliance load.

An initiating or notification circuit wired so that a single open or ground fault does not prevent operation of devices beyond the fault; the circuit leaves and returns to the same panel terminals.

A two-wire circuit that leaves the panel, serves devices, and ends at an end-of-line device; an open fault disables all devices beyond the break, though the panel still supervises the wiring.

A grouping of initiating devices on shared wiring that reports to the panel as a single point, so the panel identifies the area but not the individual device that operated.

A measured response characteristic of a smoke detector, expressed as obscuration per unit length or percent per foot, that must be checked at installation and periodically to confirm the device remains within its listed range.

A detector mounted on or in an air-handling duct that samples airflow to sense smoke, used to control fan shutdown and damper operation and to satisfy code requirements for duct smoke detection.

A resistor installed at the far end of a conventional circuit that provides a supervised normal current; the panel reads a change in that current as an alarm, open, or short condition.

The central panel that receives signals from initiating devices, processes them according to its programming, and operates notification appliances and auxiliary functions while monitoring its own power and circuits.

The formal examination of submitted drawings, calculations, and specifications by an authority to confirm the proposed system meets adopted codes and standards before installation begins.

An unintended connection between a circuit conductor and earth or the enclosure, detected by the panel's ground-fault sensing so the condition is reported as a trouble rather than left hidden.

A device that responds to thermal energy, either fixed temperature, rate-of-rise, or a combination, and is chosen where smoke detection would be unreliable or where rapid heat rise signals fire.

The wiring path connecting automatic detectors and manual pull stations to the control unit, supervised against opens, shorts, and grounds so a fault is annunciated as a trouble condition.

The recurring field activities of visually examining and functionally operating system components at code-specified intervals, then documenting results and correcting deficiencies found during the work.

A manually operated initiating device, typically a lever or pull handle, installed along the means of egress so occupants can activate the alarm without waiting for automatic detection.

The state office responsible for fire prevention and code enforcement, including plan review and inspection authority over certain occupancies and jurisdictions under Nevada fire protection statutes.

The national fire alarm and signaling code that governs installation, performance, inspection, testing, and maintenance of detection and notification systems, and is adopted in some form by Nevada jurisdictions.

The National Electrical Code, which sets requirements for fire alarm circuit wiring methods, conductor installation, overcurrent protection, and grounding that fire alarm technicians must follow alongside NFPA 72.

The supervised output circuit that powers horns, strobes, speakers, or combination appliances, sized so voltage at the farthest appliance remains within its listed operating range under alarm load.

The written authorization issued by a local or state authority allowing fire alarm installation, alteration, or repair work to proceed under approved plans and required inspections.

A programmed feature that delays general alarm for a limited period while trained staff investigate, provided the signal is acknowledged within a short window and the delay is permitted by the authority.

A document completed at system acceptance that records the installed configuration, device counts, battery calculations, and signatures confirming the system was installed and tested as designed.

The stored-energy source, usually rechargeable batteries or an engine-driven generator, that keeps the fire alarm system operational when normal building power fails or is interrupted.

The addressable data loop or path connecting intelligent devices to the control unit, carrying both power and digital communication and supervised for opens, shorts, and ground faults.

A device that senses airborne combustion products, using ionization, photoelectric, or air-sampling technology, and reports an alarm or pre-alarm to the control unit.

The condition in which the system runs on secondary batteries with no alarm active, the period used in battery calculations to prove capacity for the code-required duration.

Continuous electrical monitoring of circuit integrity and power so that opens, shorts, grounds, or loss of power are annunciated as troubles instead of silently disabling protection.

A signal indicating an off-normal condition in a system component that could impair performance if uncorrected, such as a closed valve, low battery, or duct detector trouble, distinct from fire alarm.

The standard audible evacuation cadence of three pulses followed by a pause, repeated, which is recognizable as a fire alarm and required for many occupancies unless voice evacuation is used.

An audible and visible indication that a circuit, power source, or component is not functioning properly, alerting building staff to a condition needing service rather than a fire emergency.

A strobe or other light source that flashes to alert occupants who are deaf or hard of hearing, with candela ratings and mounting heights set by code for the space covered.

An emergency communication arrangement using amplified speakers and prerecorded or live messages to direct occupants, often required in large or high-rise occupancies instead of tone-only signaling.

The loss of voltage along a conductor caused by its resistance and the current drawn, calculated to confirm appliances at the end of a circuit still receive their listed operating voltage.

A defined area or grouping of devices used by the control unit to identify where an alarm or trouble originates, and to organize annunciation and response for building occupants and responders.