Components

Not every system uses a simple single-station smoke alarm (the ones you see everyday in your home). Big buildings can have pretty complex systems with hundreds of detectors, which you can break down into three parts. The initiation device, the notification device, and the control panel.

The alarm initiation device can be manual or automatic. Either way, it's sole function is to tell the system to start an alarm. The alarm notification device is an audible and usually visual device that makes it very obvious to building occupants that there is an alarm. The last component, the control panel, is the brain of the system. It manages the entire system, and can indicate to firefighters exactly where the alarm is located.

Control panels also handle power to the alarm system and can provide backup power if necessary. Some panels will automatically notify the fire department or a central station monitoring company. These things are like snowflakes- never two of the same. Old control panels might just indicate that yes, an alarm has been activated. Modern ones will usually indicate an exact area where the alarm has sounded. Don't turn off or reset a panel until after the situation has been resolved, and keep an eye out for an additional display panel near the front door of the building (often called a remote annunciator). Don't confuse this with a control panel.

A manual pull station is that box you know all too well, if you needed to get out of a midterm in highschool. All you have to do to activate the alarm is give it a good yank. The single-action stations just say "pull", while the double-action stations will have a cover or door that you have to open before you can pull on them. These can have tamper alarms on them.