Manually actuated alarm-initiating devices commonly called fire alarm pull stations are easy to take for granted. They are found on the walls of almost every building. And, while their basic design hasn’t changed much in the last 50 years or so, they remain an important component of modern fire protection systems.
Functions And Types Of Pull Stations
A fire alarm pull station is one of two types of initiating devices used in a typical fire alarm system. There are automatic initiation devices such as smoke detectors and heat sensors that work without human intervention to activate alarms while pull stations provide the ability for a person to trigger the alarm manually.
Manual pull stations generally fall into two main types, single-action and dual-action. With a single-action alarm box, a person can activate the alarm by simply pulling the handle down.
Dual-action alarm boxes require the user to perform two actions to activate the alarm such as lifting up on the handle before pulling it down or having to break a glass panel to access it. On all types, pulling down the handle completes the circuit and locks the handle in the activated position, which sends a notification to the fire alarm control panel to trigger the alarms.
Reset The Control Panel
Once a manual pull has been activated, it must be restored to its ready position. This typically requires a special tool or key, which is used to open the alarm station.
Opening the alarm station allows the handle to revert to its original ready position. Once in its ready position, the station is closed, which allows the alarm to be reset from the fire alarm control panel.
Where Are Pull Stations Required?
NFPA requires at least one manual pull station for any fire alarm system that uses automatic fire detection devices Regardless of its occupancy classification, almost every building will require manual pull stations in addition to other, automatic initiation devices. Pull stations provide an important failsafe in the event of a malfunction in one or more of the automatic initiation devices.
The requirement for multiple safeguards comes from the National Fire Protection Association (NFPA) 101 Life Safety Code, which states that life safety should “not depend solely on any single safeguard” and that “additional safeguard(s) shall be provided for life safety in case any single safeguard is rendered ineffective.”
National Fire Protection Association (NFPA)
NFPA 101 requires at least one manual pull station for any fire alarm system that uses automatic fire detection devices such as smoke detectors and heat sensors or water flow detection devices such as sprinklers. How many of them are required depends on how large the area to be protected is and how many exits it has.
These requirements are provided in NFPA 72 National Fire Alarm and Signaling Code, which guides the design and installation of fire alarm systems, including fire alarm pull stations.
Placing The Fire Alarm
Placement of fire alarm pull stations is critical to ensure they provide the protection intendedNFPA 72 refers to fire alarm pull stations as manual fire alarm boxes. The code requires that the travel distance to the nearest pull station on a given floor must be no more than 200 feet. So, the larger the building and the longer its hallways, the more pull stations will be required. Likewise, the more exits there are in a building, the more pull stations will be required.
NFPA 72 requires a pull station within 60 inches of every individual exit, and for groups of doors that are more than 40 feet wide away from each other, there must be a pull station on both sides of the grouping. The placement of fire alarm pull stations is critical to ensuring they provide the protection intended.
Easily Accessible In Emergency
The requirements for their placement are intended to ensure that occupants leaving any area of the building can quickly and easily find and pull the alarm to warn others of the emergency on their way out.
In keeping with this idea, they must be securely mounted on the wall where they are conspicuous, unobstructed, and accessible. This means that they must be installed in such a way that people with or without disabilities can access them.
Inspection Before Installation
According to NFPA 72, visual inspections of manual fire alarm boxes are required when they are first installed and every six months after that.
Visual inspections are intended to identify any obstructions and conditions that indicate servicing may be needed, such as open or broken covers on dual-action alarms. Visual inspections may be conducted by the building owner or designated representative. However, any servicing must be done by a qualified professional.
Annual Testing
Testing is typically done as part of more comprehensive testing of the fire alarm system
Prior to testing pull stations, technicians will deactivate the alarms and strobes, which are tested separately, to avoid disturbing the building’s occupants.
When testing, one technician will pull the alarm handle to activate the pull station while another technician watches the alarm panel to confirm whether or not the notification was received that the pull station was activated. Once this is confirmed, the technician will use a key to reset the pull station.
Manual fire alarm boxes must be tested annually per the manufacturer’s instructions. Annual testing is required by NFPA 72 also. This testing is typically done as part of more comprehensive testing of the fire alarm system, which is also required annually.