A fire alarm system has a number of devices working together to detect and warn people through visual and audio appliances when smoke, fire, carbon monoxide or other emergencies are present.
Ionization-type smoke alarms have a small amount of radioactive material between two electrically charged plates, which ionizes the air and causes current to flow between the plates. When smoke enters the chamber, it disrupts the flow of ions, thus reducing the flow of current and activating the alarm.
The field of fire detection has advanced to where smoke detectors and alarm devices have combined to become life-safety systems. The purpose of an automatic fire-alarm system is to detect an occurrence, alert the control panel and proper authorities, and notify the occupants to take action.
Although photoelectric alarms are highly effective at detecting smoldering fires and do provide adequate protection from flaming fires, fire safety experts and the National Fire Protection Agency recommend installing what are called combination alarms, which are alarms that either detect both heat and smoke.
Most fire alarm systems consist of the following components: Fire alarm control panel – the system hub monitors inputs and system integrity, controls outputs and relays information. Primary power supply – primary power for your fire alarm system is usually supplied in the form of 124V or 240V AC from the power
Many fires occur at night or in a room or section that no one may be in at the time. The audible alert from the fire alarm can wake individuals up who may otherwise sleep while inhaling smoke. The alert can also provide an early signal during the day to individuals who, if not for the alarm, would not have the time needed to escape the home or building before the fire spreads out of control.
Another advantage of fire alarms is the flexibility to place them in specific rooms and areas of your choice. Although there are guidelines about certain areas to avoid, such as spots too close to bathrooms, where steam from showers and baths will inadvertently trigger the alarm, you do have options for where to install the units. For example, shared hallways for multiple bedrooms can be the location for a single fire alarm, or you can install the alarm in a bedroom that is usually closed off to other rooms.
Components of Fire alarm system
Smoke (particulate and aerosol)
Thermal detectors sense the high temperature or the temperature rise caused by a fire.
Flame detectors sense the radiation produced by a fire.
Fire-gas detectors sense the gases produced by a fire.