Fire Alarm System for Home and Business
Fire Alarm System for Home and Business, Fire alarm is a unit made of several devices, which uses visual and audio signalization to warn people about a possible fire, smoke, or carbon monoxide occurrence in the area of coverage. Fire alarms are usually set in fire alarm systems to provide zonal coverage for residences and commercial buildings.
The warning signal is either a loud siren/bell or a flashing light, or it can include both. Some fire alarm systems use additional warnings, such as sending a voice message or making a phone call.
Fire Alarms Classifications
Depending on the functionality and the integrated components, there are several classifications of fire alarm systems.
Automatic fire alarm systems
Automatic fire alarm systems are activated through fire detectors, such as smoke or heat sensors. Manual fire alarms are activated with manual call points or pull stations.
Conventional fire alarms system
Conventional fire alarms systems work as one unit and cannot pinpoint the exact area of activation unless inspected. Addressable fire alarms have a specially dedicated address for each fire alarm detector that is connected to the control panel, for easier identification of the source of the danger.
One-stage fire alarm systems
One-stage fire alarm systems warn everyone in the building that a sensor has been activated. Two-stage fire alarm systems warn only certain people who are authorized to take appropriate action before the second stage. This system is designed to serve large public areas (for example, healthcare facilities) to prevent panic and inadequate frightful response.
Fire Alarm Control Panels
Fire control panel is the “brain” of the fire detection and alarm system. It is responsible for monitoring the various alarm “input” devices such as manual and automatic detection components, and then activating alarm “output” devices such as horns, bells, warning lights, emergency telephone dialers, and building controls.
Fire Control panels may range from simple units with a single input and output zone, to complex computer driven systems that monitor several buildings over an entire campus. There are two main control panel arrangements, conventional and addressable, which will be discussed below.
Conventional or “point wired” fire detection and alarm systems were for many years the standard method for providing emergency signaling. In a conventional system one or more circuits are routed through the protected space or building.
Fire alarm addressable system also monitors the condition of each circuit, identifying any faults which may occur. One of the advancements offered by these systems is their ability to specifically identify where a fault has developed. Therefore, instead of merely showing a fault along a wire, they will indicate the location of the problem. This permits faster diagnosis of the trouble, and allows a quicker repair and return to normal.
Fire Detectors
When present, humans can be excellent fire detectors. The healthy person is able to sense multiple aspects of a fire including the heat, flames, smoke, and odors. For this reason, most fire alarm systems are designed with one or more manual alarm activation devices to be used by the person who discovers a fire
Thermal detectors are the oldest type of automatic detection device, having origin in the mid 1800’s, with several styles still in production today.
Smoke detectors are a much newer technology, having gained wide usage during the 1970’s and 1980’s in residential and life safety applications. As the name implies, these devices are designed to identify a fire while in its smoldering or early flame stages, replicating the human sense of smell.
Flame detectors represent the third major type of automatic detection method, and imitate the human sense of sight. They are line of sight devices that operate on either an infrared, ultraviolet or combination principle. As radiant energy in the approximate 4,000 to 7,700 angstroms range occurs, as indicative of a flaming condition, their sensing equipment recognizes the fire signature and sends a signal to the fire alarm panel.
Fire Alarm Cable
Fire alarm cables are designed to ensure that the interconnections between fire alarm systems operate correctly for an appropriate length of time in the event of an evacuation.