How Do Fire Alarm Systems Work?
Understand Fire Alarm Basics & Bring Your Building Up To Code
Understanding fire code requirements is essential if you own, manage, or build commercial structures. All too often people confuse fire alarms with fire sprinklers or smoke detectors. Fire alarms are far more complex than those individual systems.
In this blog, you will learn what the role and primary components of a fire alarm system are and the basics of how these components work together to protect your building and its occupants in the event of a fire.
This article serves as a 101 class in fire alarms – what is the main function, the components and how they work together with your entire fire protection system.
What is the Main Purpose and Function of a Fire Alarm System?
• A fire alarm system detects fires and alerts both building occupants and emergency personnel from a centrally monitored location.
• A fire alarm system also identifies the location of fires within the building and detects when errors occur in wiring and connections.
• A fire alarm system has four key functions: detect, alert, monitor, and control. The full system is basically a network of devices, appliances, and control panels that carry out these four functions.
Five key elements that make up every fire alarm system:
1. Initiating Devices: initiating devices detect smoke or a fire. These devices include smoke detectors, heat detectors, sprinkler water flow sensors, and fire alarm pull stations.
2. Indicating Appliances: indicating appliances sound the alarm and alert occupants to the fire hazard. They may use horns, chimes, bells, and in some situations, even strobe lights for the hard of hearing and deaf. These appliances are deliberately loud and designed to encourage everyone to leave the building quickly.
3. Fire Alarm Panel: the fire alarm control panel is the user interface and central monitoring and controlling element of the system. It has a display showing the current state (alarm or no alarm) of the fire alarm system and a touch pad, which allows onsite personnel to program, troubleshoot, silence, and reset the system. The fire alarm panel monitors and has supervisory function over all of the system’s initiating devices, indicating appliances, and all related telephone ties, field wiring, and its circuit cards and internal wiring. It is also from the fire alarm panel that a call is sent out to a monitoring agency which makes sure emergency personnel are alerted.
4. Power Supplies: cover main power from the breaker, have (2) 12V batteries as backup for 24 hours, and sometimes a generator as backup power. The batteries will take over should the power fail, allowing the system to continue protecting the building from fire for 24 hours. A generator is used for power outages lasting longer than 24 hours.
5. Auxiliary Devices: many additional devices can be added onto a fire alarm system for additional reinforcement. These include things like visual LED indicators showing which zone in a building a fire alarm was triggered, remote annunciators, alarm silence switches, electromagnetic door holders, fire doors, elevator capture and shutdown, etc.
These systems can be simple or elaborate depending on the needs of the facility. Creating or updating a fire alarm system for your building can be a challenging task and consulting with the professionals at Spartan Fire Protection and professional electricians is a must if you want to stay up to code.
Fire Alarm Systems Have 3 States
There are three states of operation: Normal, Alarm, and Trouble.
When all devices, appliances, wiring, and circuitry are operating correctly, and no alarms are activated, the system is operating in a Normal State.
When an initiating device is activated, the system goes into an Alarm State. The indicating appliances will sound, alerting building occupants to the danger, and the alphanumeric display on the control panel will indicate from which zone of the building(s) the alarm is originating from so that emergency personnel can quickly respond to the correct area.
Should a short develop in the circuits connecting the fire alarm panel and initiating devices, or within the panel’s wiring or zone cards, or if the system’s phone line connection is not functioning, then the system goes into Trouble State. The panel will indicate which zone the issue is in, and a buzzer will sound to alert maintenance personnel to the problem. While the buzzer is loud enough to be heard, it is not as loud and will not be confused with an actual alarm.
What Happens When A Fire Alarm System is Activated?
When a fire starts, the smoke or heat will activate one of the initiating devices, or someone will activate the manual pull station, alerting the fire alarm system to the fire – putting it in alarm mode.
When the system goes into alarm mode, three things should happen:
• The indicating appliances should sound the alarm.
• A call goes out to the monitoring company.
• Fire suppression systems may also be activated to help fight the fire until emergency personnel arrives.
How Do You Disarm a Fire Alarm?
It is important that the building manager or maintenance crew understand how to read and use the fire alarm panel, especially if it is in trouble state or is experiencing false alarms. There are alarm and trouble silence options as well as a system reset option.
Need Help Staying Up To Code?
Failing to consult with professionals about fire alarms and fire protection can lead to disastrous consequences – loss of property, loss of investment and most importantly, loss of life. Spartan Fire Protection has been bringing buildings up to code and maintaining fire alarm and fire protection systems throughout Houston to great reviews.
If you are getting ready to build, or if your current fire protection system needs updating or maintenance – give our experts at Spartan a call today.