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  2. Fire alarm notification appliance - Wikipedia

    en.wikipedia.org/wiki/Fire_alarm_notification...

    From NFPA 72, 2002 Edition: “7.4.2.1* To ensure that audible public mode signals are clearly heard, unless otherwise permitted by 7.4.2.2 through 7.4.2.5, they shall have a sound level at least 15 dB above the average ambient sound level or 5 dB above the maximum sound level having a duration of at least 60 seconds, whichever is greater ...

  3. Alarm device - Wikipedia

    en.wikipedia.org/wiki/Alarm_device

    an alarm clock that sounds an alarm at a pre-set time, often used to wake a person up or remind them of an event. a fire alarm which is used to give occupants of a building early warning of a potential fire and give them time to evacuate. warning devices on a vehicle that sound when it is moving in an unexpected direction, such as reversing,

  4. Fire alarm system - Wikipedia

    en.wikipedia.org/wiki/Fire_alarm_system

    A fire alarm control panel Fire alarm speaker and pull station. Fire alarm systems are composed of several distinct parts: Fire alarm control panel (FACP), or fire alarm control unit (FACU): This component, the hub of the system, monitors inputs and system integrity, controls outputs, and transmits information.

  5. Fire alarm call box - Wikipedia

    en.wikipedia.org/wiki/Fire_alarm_call_box

    When the box is activated by turning a knob or pulling a hook, a spring-loaded wheel turns, tapping out a pulsed electrical signal corresponding to the box's number. [1] A receiver at fire headquarters announces the alarm through flashing lights or tones, or via a pen recorder, and the box number is matched to a list of box locations.

  6. Manual fire alarm activation - Wikipedia

    en.wikipedia.org/wiki/Manual_fire_alarm_activation

    Many modern fire alarm pull stations are single-action and only require the user to pull down a handle to sound the alarm. Other fire alarm pull stations are dual-action, and as such require the user to perform a second task before pulling down, such as lifting or pushing in a panel on the station or breaking a glass panel with an attached hammer.

  7. PASS device - Wikipedia

    en.wikipedia.org/wiki/PASS_device

    In the United States, the National Fire Protection Association sets standards for PASS devices in NFPA 1982. [ 1 ] The PASS device is normally used in conjunction with breathing apparatus; it is a small, battery-powered device attached to the self-contained breathing apparatus (SCBA) harness which enables the firefighter to summon help by ...

  8. Constant false alarm rate - Wikipedia

    en.wikipedia.org/wiki/Constant_false_alarm_rate

    However, in most fielded systems, unwanted clutter and interference sources mean that the noise level changes both spatially and temporally. In this case, a changing threshold can be used, where the threshold level is raised and lowered to maintain a constant probability of false alarm. This is known as constant false alarm rate (CFAR) detection.

  9. Federal Signal Modulator - Wikipedia

    en.wikipedia.org/wiki/Federal_Signal_Modulator

    The system uses a distinctive "WHOOP" tone that was originally produced for Federal Signal's line of fire alarms. The system is tested on the second Monday of every month at 6:00pm. [6] Alaska has many Federal Signal Modulators and Eclipse 8s on their All Hazard Siren System. They sound for tsunamis as well.