Table of Contents
- 1 What is initiating device in fire alarm?
- 2 What are the alarm initiation devices?
- 3 Which alarm initiating device is activated by a rapid rise in temperature?
- 4 Which of the following is an example of an initiating device?
- 5 What are the disadvantages of fire alarm systems?
- 6 What is the purpose of a fire alarm system?
What is initiating device in fire alarm?
According to NFPA 72, fire alarm initiating devices are defined as devices used to manually or automatically signal a fire alarm system to initiate responses from equipment and people.
What are the alarm initiation devices?
The initiating devices in a fire alarm system are those that detect signs of a possible fire and activate an alarm. They are the system’s triggers and the most visible aspect of the fire alarm system. Fire alarm initiating devices include smoke detectors, sprinkler water flow switches, manual pull stations, and more.
What is an initiating device circuit?
In a fire alarm system, the Initiating Device Circuit (IDC) is an input circuit or detection circuit: it carries the alarms detected by devices like flow switches, pull stations, heat detectors, tamper switches, etc. If the wire loses continuity, the panel will show that there’s trouble on the circuit.
How can fire alarms be activated?
Photoelectric smoke detection uses a steady beam of light. Once smoke particles enter the internal chamber of the device, the particles scatter the beam and redirect it to a photocell, which then triggers the alarm.
Which alarm initiating device is activated by a rapid rise in temperature?
Heat detectors are activated by either melting a fusible material, changes in electrical current induced by heat loads on bimetallic metals, destruction of the device itself by the heat, or by sensing a rate of ambient temperature rise.
Which of the following is an example of an initiating device?
Initiating devices: These components act as inputs to the fire alarm control unit and are either manually or automatically activated. Examples would be devices such as pull stations, heat detectors, duct detectors, and smoke detectors. Heat and smoke detectors have different categories of both kinds.
What activates a fire alarm?
When it comes to smoke alarms, there are two main types: photoelectric and ionization. Ionization smoke detection employs the use of ions and electrons that whizz around electrodes. When smoke enters the ionization chamber, it sticks to the ions, which disrupts the chemistry and activates the alarm.
Which component of a fire alarm system allows occupants to activate the fire alarm?
Automatic initiating devices – automatic initiation devices trigger the fire alarm system automatically when a fire happens. These devices include heat, flame and smoke detection. When heat, flames or smoke is detected, the devices send a signal to a central control panel that activates the system.
What are the disadvantages of fire alarm systems?
A couple other disadvantages fire alarm system inspectors point out is wireless systems have limited range and don’t have centralized monitoring. Range can be a problem for large offices or homes, since a weak wireless connection may cause the system to not operate reliably.
What is the purpose of a fire alarm system?
The purpose of a fire alarm system is to detect a fire and provide warning to building occupants to evacuate the premises. Automatic devices, such as smoke and heat detectors, sense the fire and then activate audiovisual devices.
How is a fire alarm activated?
A fire alarm pull station is an active fire protection device, usually wall-mounted, that, when activated, initiates an alarm on a fire alarm system.
What are the components of a fire alarm system?
Fire Alarm System Components. A fire alarm system consists of three basic components: detection devices (smoke and heat detectors), alarms and notification (strobes/horns), and suppression devices (sprinklers or devices that use gas or chemicals).