How Does a Fire Alarm System Work?

Before we tackle on how does a fire alarm system work, let us first know what a fire alarm system is. A fire alarm system is an “active fire protection” system that controls all the fire alarm modules in a building. When we say “active fire protection”, it refers to items or systems that can be “activated” mechanically or electronically. Fire alarm systems are composed of alarm initiating devices (smoke detectors and heat sensors), alarm notification appliances (sirens or devices that produce loud noises), fire control units (sprinkler systems or fire extinguisher systems), power supplies and wirings. Fire alarm systems notify the occupants of a building or a house of a possible fire so that the occupants can either evacuate for safety or extinguish the fire before it could spread out and become uncontrollable.

So how does a fire alarm system works? The fire alarm system can be set off automatically by smoke detectors, heat detectors or manually. These sensors are set to detect certain levels of heat or smoke that could be an indication of fire. A loud bell or a siren, sometimes accompanied by blinking or flashing lights for individuals who have hearing problems, blasts to alert occupants in the building. To truly understand how a fire alarm system works, let us go further into the components of the fire alarm system. In a fire alarm system there is always a smoke detector to detect smoke or fire.

How does a fire alarm system work by way of smoke sensor? There are two types of smoke detectors. These are the “optical detector” and the “ionization detector”. The optical smoke detector detects smoke by using light sensors (infrared LED). When smoke particles pass thru the chamber of the optical detector, it scatters light that triggers the alarm. In the ionization detector, if the smoke particle enters the chamber of the ionization detector it will reduce air ionization inside the chamber of the ionization detector and triggers the alarm. Another aspect of how a fire alarm system works is the heat sensor or also called thermal sensor. A fire alarm system works by way of heat sensor in quite simple way. The heat sensor monitors the temperature in a room and any abrupt rise or sudden extreme change in temperature triggers the fire alarm.

Some fire alarm systems have automatic dialers that could dial an emergency number to contact the local fire department.