HI Fire Alarm flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

NFPA 72

The National Fire Alarm and Signaling Code, which covers the application, installation, location, performance, inspection, testing, and maintenance of fire alarm systems and their components.

Authority having jurisdiction

The organization, office, or individual responsible for approving equipment, installations, and procedures, and for granting final acceptance of a fire alarm system.

Initiating device circuit

The circuit connecting the control unit to initiating devices such as smoke detectors, heat detectors, and manual pull stations, which reports alarm or supervisory conditions to the control unit.

Notification appliance circuit

The circuit connecting the control unit to notification appliances such as horns, strobes, and speakers, which provides audible and visible signals to building occupants.

Addressable device

A device whose individual identity is reported to the control unit, allowing the system to annunciate the specific device that has gone into alarm or trouble.

Photoelectric smoke detector

A smoke detector that uses a light source and a photosensor to detect light scattered by smoke particles, responding faster to large-particle smoldering fires.

Ionization smoke detector

A smoke detector that uses a small radioactive source to ionize air in a chamber and detects changes in current caused by smoke particles, responding faster to small-particle flaming fires.

Rate-of-rise heat detector

A heat detector that alarms when the temperature rises faster than a set rate, typically around 15°F per minute, rather than at a fixed temperature.

Duct smoke detector

A smoke detector installed in an HVAC duct to detect smoke being transported through the ductwork, typically causing shutdown of the air-handling unit on alarm.

Isolator module

A module on an addressable loop that isolates a short-circuited segment so that the remaining devices on the loop continue to communicate with the control unit.

Monitor module

An addressable module that supervises a dry contact from another system and reports its open or closed state to the control unit as an alarm or supervisory condition.

Class A circuit

An initiating or notification circuit that continues to operate through a single open or ground fault because the circuit is wired out and back to the control unit.

Class B circuit

An initiating or notification circuit that may lose the affected portion of the circuit on a single open or ground fault, since the circuit is wired as a single path.

End-of-line resistor

A resistor installed at the end of a conventional initiating device circuit to supervise the circuit, producing a trouble on an open and an alarm on a short.

Smoke detector spacing

On a smooth ceiling, the maximum spacing between smoke detectors is 30 ft (9.1 m), with the first detector within 15 ft (4.6 m) of the wall.

Manual pull station travel

Manual pull stations must be located so that no point on a floor requires travel of more than 200 ft (61 m) to reach one, and at each required exit.

Public mode audibility

Audible signals in public mode must produce at least 15 dBA above ambient or 5 dBA above the maximum sound level of at least 60 seconds duration, whichever is greater.

Sleeping area audibility

Audible signals in sleeping areas must be at least 75 dBA at the pillow or 15 dBA above ambient, whichever is greater, and must not exceed 110 dBA at the pillow.

Strobe synchronization

Visible notification appliances within a protected area must flash in unison so that unsynchronized flash patterns do not create a seizure hazard for occupants.

Strobe candela rating

The listed light output of a visible notification appliance, which determines its coverage area and must be selected according to room size and mounting height.

Secondary power duration

Battery backup must operate the system for 24 hours of standby followed by 5 minutes of alarm signaling, unless the code or authority having jurisdiction requires otherwise.

Battery capacity formula

Capacity in amp-hours equals standby current times standby hours plus alarm current times alarm hours, with a derating factor applied for battery aging and temperature.

Battery recharge requirement

Batteries must be recharged to 80 percent of capacity within 24 hours and to full capacity within 48 hours after a discharge.

Circuit survivability

Circuits that must continue to operate during a fire, such as notification circuits in high-rise buildings, require a 2-hour fire-rated pathway.

Ground fault detection

The control unit must supervise its circuits for ground faults, and a ground fault on a supervised circuit produces a trouble signal.

Sensitivity testing

Smoke detectors must have their sensitivity tested at the frequency specified by the code and after any cleaning, repair, or relocation of the detector.

Record of inspection

A document that records the date, the devices tested, the results of testing, and the name of the person who performed the inspection and testing.

Battery load test

A test that verifies the battery can deliver its rated capacity under load; the battery must be replaced if it fails the test or exceeds its service life.

Detector wall clearance

Detectors must be installed at least 4 in (100 mm) from a wall and at least 36 in (900 mm) from an air supply diffuser to avoid dilution of smoke.

Heat detector spacing

On a smooth ceiling, the maximum spacing for heat detectors in the 135°F to 174°F range is 50 ft (15.2 m), with the first detector within 25 ft (7.6 m) of the wall.

Elevator recall

A fire alarm function that, on a designated initiating signal, causes elevators to return to a designated floor and open their doors, per code and elevator manufacturer requirements.

Record of completion

A document retained by the building owner that records the installed system configuration, including as-built drawings, device lists, and calculations, and is available to the authority having jurisdiction.