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1 – Pull Stations for Fire Protection Systems

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#122 – Pull Stations for
Fire Protection Systems: A
First Line of Defense
August 22, 2018
A working fire alarm pull station
supports prompt evacuation and
swift action from first responders
When somebody “pulls the fire alarm,” they’re usually talking about fire
alarm pull stations. For more than 50 years, some form of these typically
red boxes have been found on the walls of most large buildings in the
United States.
In this article, we’ll cover how pull stations work, why they’re important,
and what to look for when purchasing one.
How does a fire alarm pull station
work?
Sometimes referred to as “pull switches,” fire alarm pull stations—often
featuring a T-bar handle, as shown below—activate fire alarm systems.
Pull stations with a T-bar handle are
easily recognized and activate with a single downward motion.
Source: Potter
These systems can also be activated by other initiating devices, such as
automatic heat and smoke detectors, but what follows is the same:
indicating appliances, such as horns or strobe lights, direct occupants to
leave the area. Pull stations send a signal to the control panel, and if the
fire alarm is monitored, the control panel then usually sends a message
to a company’s monitoring service, which transmits that message to first
responders. In some cases, a signal is transmitted directly to a fire
department.
The status of pull switches and other essential components are displayed
on fire alarm control panels like this one. Source: Photographed at
Oklahoma State University and uploaded to Wikimedia Commons
It’s a less commonly-known fact that most pull stations don’t cause fire
sprinklers to spray water. Many fire alarm systems may monitor fire
sprinkler systems – and sound the alarm when sprinklers discharge – but
their purpose is to alert bystanders and authorities to danger.
Pull stations are redundant—and
that’s (part of) the point
The National Fire Protection Association (NFPA) authors guidelines used
by state and local governments to write fire code. At the core of NFPA’s
philosophy is redundancy – the effort to guarantee that when one life
safety system fails, another takes its place.
From the 2018 edition of NFPA 101
4.5.1 Multiple Safeguards. The design of every building or structure intended for human
occupancy shall be such that reliance for safety to life does not depend solely on any
single safeguard. An additional safeguard(s) shall be provided for life safety in case any
single safeguard is rendered ineffective.
Attacking the problem of fire safety from multiple angles makes
buildings much safer. Safety features – from fire extinguishers to fire
escapes – are redundant in the best possible sense of the word.
Working, fail-safe fire prevention systems have become more
widespread as the frequency of fires has declined. But today’s fires, while
drastically fewer in number, remain just as deadly and devastating when
they occur, making these fail-safes as critical as ever.
Thomas Peele, a journalist with The Mercury News, reported on a 2018
fire in San Jose, California that injured 15 people and displaced more
than 100. Peele learned that an untested and uncertified fire alarm
system failed to activate when fire broke out in a second-story unit at
Summerwind Apartments. Fire inspector Andrew Whyte uncovered
several additional fire safety violations, including problems with exit
signs, emergency lights, and other fire prevention equipment. An
inspection in 2011 had found “that the alarm at Summerwind was not
certified as working,” but the issue was never remedied.
Pull stations, required in
nearly every building, must be
nearby
Every fire alarm system can be activated in one of several ways, but
according to NFPA guidelines, manual fire alarm initiation is a
requirement common to almost every building requiring a fire alarm
system. Automatic detection can be used in place of manual activation
only when explicitly allowed.
As a general rule, all kinds of public buildings – theaters, schools,
daycares, hospitals, prisons, apartments, hotels, and businesses – need at
least one alarm pull switch, even when automatic detection devices are
connected to the alarm system. NFPA 101: Life Safety Code, available for
free at NFPA.org, spells out these requirements.
From the 2018 edition of NFPA 101
9.6.2.6* For fire alarm systems using automatic fire detection or waterflow detection
devices to initiate the fire alarm system in accordance with Chapters 11 through 43, not
less than one manual fire alarm box, located as required by the authority having
jurisdiction, shall be provided to initiate a fire alarm signal.
When boxes are required, they must be placed near exits and along walls
at a prescribed distance.
From the 2018 edition of NFPA 101
9.6.2.3 A manual fire alarm box shall be provided as follows, unless modified by another
section of this Code:
(1) For new alarm system installations, the manual fire alarm box shall be located within
60 in. (1525 mm) of exit doorways.
(2) For existing alarm system installations, the manual fire alarm box either shall be
provided in the natural exit access path near each required exit or within 60 in. (1525
mm) of exit doorways.
9.6.2.5* Additional manual fire alarm boxes shall be located so that, on any given floor
in any part of the building, no horizontal distance on that floor exceeding 200 ft (61 m)
shall need to be traversed to reach a manual fire alarm box.
9.6.2.7* Manual fire alarm boxes shall be accessible, unobstructed, and visible.
Where multiple doors are clustered together, as pictured below, an alarm
box is required on each side.
From the 2018 edition of NFPA 101
9.6.2.4 Manual fire alarm boxes shall be mounted on both sides of grouped openings
over 40 ft (12.2 m) in width, and within 60 in. (1525 mm) of each side of the opening.
Pictured: A grouped opening of doors at the Roy Wilkins Auditorium in
Saint Paul, Minnesota; an alarm box is required on each side of the
grouping. Source: Wikimedia
NFPA provides straightforward
installation guidelines
NFPA 72: National Fire Alarm and Signaling Code establishes installation
criteria for “initiating devices,” a term that covers everything from
waterflow detectors to manual fire alarm boxes. First and foremost, only
qualified installers should make changes to fire alarm systems.
From the 2016 edition of NFPA 72
10.5.2.1 Fire alarm systems and emergency communications systems installation
personnel shall be qualified or shall be supervised by persons who are qualified in the
installation, inspection, and testing of the systems.
10.5.2.2 State or local licensure regulations shall be followed to determine qualified
personnel.
10.5.2.3 Personnel shall provide documentation of their qualification by one or more of
the following:
(1) Registration, licensing, or certification by a state or local authority
(2) Certification by an organization acceptable to the authority having jurisdiction
(3) Manufacturer’s certification for the specific type and brand of system provided
Further guidelines ensure the visibility, accessibility, and proper function
of alarm activation devices.
From the 2016 edition of NFPA 72
17.14 Manually Actuated Alarm-Initiating Devices.
17.14.1 Manually actuated alarm-initiating devices for initiating signals other than for fire
alarm shall be permitted if the devices are differentiated from manual fire alarm boxes
by a color other than red and labeling.
17.14.2 Combination manual fire alarm boxes and guard’s signaling stations shall be
permitted.
17.14.3 Manually actuated alarm-initiating devices shall be securely mounted. 17.14.4
Manually actuated alarm-initiating devices shall be mounted on a background of
contrasting color.
17.14.5 The operable part of a manually actuated alarm initiating device shall be not
less than 42 in. (1.07 m) and not more than 48 in. (1.22 m) from the finished floor.
Two terms are introduced later in this section:
Single-action boxes require only one action to operate (i.e.,
a single pull on a lever)
 Double or dual-action boxes require two actions – lift and
pull.
The 2016 edition of NFPA 72 continues:

17.14.6 Manually actuated alarm-initiating devices shall be permitted to be single action
or double action.
17.14.7* Listed protective covers shall be permitted to be installed over single- or
double-action manually actuated alarm initiating devices.
17.14.8 Manual fire alarm boxes shall comply with 17.14.8.1 through 17.14.8.6.
17.14.8.1 Manual fire alarm boxes shall be used only for fire alarm initiating purposes.
17.14.8.2 Manual fire alarm boxes shall be installed so that they are conspicuous,
unobstructed, and accessible.
17.14.8.3* Unless installed in an environment that precludes the use of red paint or red
plastic, manual fire alarm boxes shall be red in color.
What features should I look for?
Listings are an indicator of a fire alarm pull station’s quality. A listing or
approval from experts in product testing, such as UL, ensures that
manufacturers have taken certain precautions against damage. A pull
station meeting UL 38, the company’s Standard for Manual Signaling
Boxes for Fire Alarm Systems, has been examined, tested, and confirmed
to resist problems caused by impact, use, corrosion, weather, and other
factors.
If the box features a metal body, it should be treated or coated with
corrosion-resistant material. In most cases, a single-action pull station
works, but a dual-action pull model – those that require two gestures to
activate – may be best in areas where the alarm may be unintentionally
activated by impact (or by a prankster). All boxes should feature a handle
that cannot be reset, except by authorized personnel, when pulled.
Single-action pull stations from Viking Group (manufactured by Potter
Electric Signal Company) exceed these standards. They’re made with
corrosion-resistant cast-iron bodies that mount to a standard single
gangbox – boxes sized for a single light switch or a pair of electrical
sockets. These stations include a terminal block, allowing for wires to
connect to alarms with no splicing required.
Viking’s boxes meet the standards of UL 38 and have listings or
approvals from UL, CSFM, FM, and the New York City Department of
Buildings. Locking handles prevent premature termination of the fire
alarm’s signal and hex-keyed entry and a die-cast body restrict access to
authorized personnel.
Viking pull stations are ready for pre-orders at QRFS. To place yours, call
us at 888.361.6662.
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