Three different fire engine companies (or fire stations) receive the call to go fight that one fire. Usually that means its one really, really big fire.
The above is partially correct, but still incorrect. A multi-alarm fire is given its' alarm number (one-alarm, two-alarm, etc) based on the number of "units" and firefighters present at the fire.
Here in Kern County, two engine companies may respond, and the fire may still be classified a one-alarm fire. I have dispatched 2 engine companies (7 units, 23 firefighters) to a warehouse fire, that was coded a three-alarm fire.
Not every city or county uses this method of multi-alarms. It is however, the most widely used system.
Other factors also play into the multi-alarm system. Such as firefighters needing relief from exhaustion, the fire spreading to other buildings/structures, or the fire simply being to big to contain with the resources available at the fires' location. These will almost always result in more engine companies being called in to assist, thus raising the multi-alarm code to the next level, or higher.
Its a really big fire and you need to stand clear
Firefighters call a large fire a 'three alarm' fire.
Fire Alarm
The fire alarm rang
To open a fire alarm, you typically need to break the glass or press a button on the alarm panel. This will activate the alarm and alert others of a fire emergency.
The fire alarm technician is in charge of the installation of fire alarm systems. Fire alarm systems include addressable or conventional alarm control panels, smoke detectors, heat detectors, manual button alarms, sirens and strobes, signs, etc. A professional fire alarm system is large with professional addressable bus lines alarm systems, addressable detectors for building fire security, or other special field fire security. So, the fire alarm technician should be knowledgeable in alarm systems working principles and installation.
The Fire Alarm was created on 1936-03-09.
Mildred initially called the fire alarm about Montag.
Some fire alarm systems are directly connected to the fire service so that wehn the fire alarm is triggered, the fire department are automatically called. If not, then call the emergency services and ask for fire service.
To effectively shut off a fire alarm, locate the alarm panel and enter the code or use a key to silence the alarm. If you cannot do this, contact the fire department for assistance.
The fire alarm beeps once to alert people of a potential fire or emergency situation.
Tulsa Fire Alarm Building was created in 1931.