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Exit Door Hardware & Life
Safety
Don't touch that exit device!
When considering making changes in an exit device,
also known as a panic hardware or fire exit hardware,
first be sure you understand why it is there and
what effect any changes you make will have on
code compliance, life safety and security.
The exit device usually
comes to the attention when a building owner wants
to remove or override its functions to provide
extra or extreme building security. A company
may be losing products or work time from its customers
or employees by unauthorized use of an exit door.
The danger arises when a locksmith or security
installer is called in to add additional locks
and possibly replace the existing exit devices.
In many cases the result of the modification is
a violation of the life safety code.
Life safety codes require
the use of exit devices in specific situations,
and most codes prohibit the use of
any other lock or mechanism on the door that would
prevent the use of the device or confuse the user.
The primary purpose of an exit device is to protect
life safety by providing free egress to occupants
of a building or room. These devices are designed
for easy use, even in the dark. The independent
testing laboratories that test them require that
they be relatively easy to operate, so they can
be used by small children and physically impaired
adults.
Panic Devices or Fire Devices?
There is a distinct difference
between panic and fire devices, which carry a
fire label. Latching devices or locks on fire
doors must be self latching. The latch bolt cannot
be retracted to prevent the door from latching
when closed. The other major requirement for fire
doors is that they be self-closing, which requires
a door closer. Wall magnets or hold-open door
closers can be used to keep fire doors in the
open position but close them automatically in
case of fire. Electric latch retraction devices
can be used, again only when tied into the fire
alarm system.
Dogging is the mechanical
or electrical retraction of a latchbolt
to provide push/pull operation during heavy
traffic periods, to reduce wear on the mechanical
parts.
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Fire doors are normally not
found on the outside or perimeter doors, where owners
normally want to add security. However, there are
sections of a building that an owner wishes to separate
which do contain fire exit devices and doors. It
is necessary to understand that most building codes
do not allow any machining or altering to fire doors
or fire exit devices in the field. Holes over 1"
in diameter cannot be drilled into a fire door,
except for cylinder holes.
A fire exit device not only
provides egress but also maintains building separation,
so if there is a fire, the fire door and all of
the products mounted to it will prevent the spread
of the fire. Because this requires that it be
constantly latched, a fire exit device must be
designed so it cannot be dogged. It also is made
with heavier parts than a standard panic device,
as well as additional parts, which cause the latch
bolt to deadlock in the event of a very hot fire
over a period of time. At this point, any occupants
in the room would have succumbed to the fire and
containment of the fire would be the primary objective.
Exit Devices vs. Locksets,
Push/Pull Latches & Others
The main criterion that
allows the use of a lockset in a public building
rather than an exit or fire device is low occupancy.
What constitutes “low occupancy” really depends
on the local building codes, so any time it is
suggested that an exit or fire exit device be
removed and replaced with any other type of lock,
be sure to get approval in writing from the authority
having jurisdiction. This would be the fire marshall,
not the building owner.
Push/Pull latches, sometimes referred to as a
hospital latch, are also used to latch doors in
rooms with low occupancy, where the code does
not require a panic or fire device. Hospital latches
provide the same easy egress as the panic device
but do not have a full-width bar.
Classifications used by
independent testing laboratories differentiate
panic exit devices from exit locks. An exit lock,
otherwise known as a panic alarm, typically consists
of a paddle with a dead bolt.
Depressing the paddle retracts
the deadbolt, allowing egress through the door
and at the same time generating an alarm. Exit
locks are designed for locking a door but do not
provide the life safety features of exit or fire
exit devices. For example, they are not designed
for high frequency use and may be difficult for
a small child or an adult with a disability to
use.
Additional Locks?
The safety code that most
model building codes are based on, NFPA 101T Life
Safety Code, says that no other lock may be installed
on a door equipped with a panic or fire exit device.
It goes on to state that even a chain hanging
nearby would be in violation of the life safety
code if it is there for the intention of locking
the exit device.
The main criterion for an
exit or a fire exit device is that it must open
in one motion. Adding an exit lock or a dead bolt
with a thumb turn could cause confusion or panic
if someone were to walk up to a door in a dimly
lit room and push on an exit device. They should
be able to expect that the door would release
with no other motion.
"Special Locking Arrangement"
is a relatively new term in the door hardware
industry. When permitted, special locking allows
additional hardware to be added to an opening
to slow down the unauthorized use of an exit.
The special locking equipment must meet certain
requirements and is attached to a door in addition
to the exit or fire exit device. The second locking
operation must follow the Life Safety Code with
several requirements, including being tied into
the fire alarm system. On activation of the fire
alarm the second locking arrangement must release
immediately. Electromagnetic locks are popular
in this operation. Von Duprin combines special
locking and the exit or fire exit device, meeting
both requirements of life safety and security.
This type of combined device is actually classified
by Underwriters Laboratories (UL) as a “Controlled
Panic Exit Device”.
When a store owner wants
to add an electromagnetic lock to an exit door
or replace an exit device with an electromagnetic
lock, there are consequences to consider. Because
all panic devices or fire devices are listed in
Warnock-Hersey, UL or other listing agency manuals,
any panic or a fire exit device that is removed
from a door should be replaced with one that is
listed under the same category. The only exception
is if the device is being replaced with one listed
in one of the third-party testing manuals as a
Controlled Panic Exit Device.
Electric
Strikes
Many
times electric strikes are used with a panic exit/fire
exit device. When an electric strike is used with
a panic or fire exit device, it must have the
same strength as the latch bolt or security will
be reduced. Typically, an ANSI Grade 1 strike
should be used. When using an electric strike
with a panic device, make sure it is recommended
by the manufacturer of both the panic device and
the electric strike.
When using an electric strike
with a fire exit device, it is necessary that
manufacturers of both items recommend their use
as a system. When an electric strike is used with
a fire device, it must be non-fail safe (fail
secure) to protect the integrity of the fire exit.
Most requirements that allow the use of an electric
strike with a fire exit device permit this use
only at the bottom of the stairwell, where the
door will not have to unlock in the event of a
fire. Stairwell doors on all floors above must
be designed so people cannot be trapped in the
stairwell in the event of a fire. Because fire
doors must be self latching, there usually is
little opportunity to use an electric strike on
a fire door. On a single-floor building where
fire doors are used to separate parts of a building,
a fail-secure electric strike can be used with
a rim or mortise lock fire exit device.
The Effect of Door Design
Certain types of exit doors
may affect security or safety, and therefore lock
selection. When building designers or store owners
use full glass doors, they make it easier for
someone to break the glass and release the exit
device. To counteract this possibility, they may
try to add other locks and security devices and
end up compromising life safety.
Because the use of exit
devices is required by life safety codes, inswinging
doors have been prohibited on most occupancies.
When adding or changing locks on an inswinging
door, the first consideration is whether the opening
requires an exit device. If it does, it will also
be necessary to re-swing the door so it opens
outward. This situation is more common on older
buildings.
For a single door, a rim-type
exit device is easier to install and maintain,
and it allows more adjustment if the door warps
or the frame moves as the building settles. If
the door has been pre-prepped for it, a device
with a mortise latch also can be used.
Door
Coordinator
Pushing the
inactive door will push the active door out
of the direction of travel. On this application,
a coordinator is recommended to hold the active
door open until the inactive door closes.
Depressing trigger or inactive door side will
allow active side to close. |
Pairs of doors without a mullion
will require at least one vertical rod exit device,
but two rim devices may be used on pairs separated
by a mullion. This is the most secure and also the
easiest installation, and it requires the least
amount of maintenance. Pairs of doors without an
overlapping astragal can accommodate two vertical
rod or two concealed vertical rod devices. Pairs
of doors will also accept a vertical rod device
on one leaf with a mortise or rim device on the
other. Most manufacturers recommend the use of a
mortise on the second leaf. When pairs of doors
have an overlapping astragal it is imperative that
only one leaf utilize a vertical rod exit device,
since with two vertical rod devices, one door could
not be opened until the other was opened first.
Double Egress Pair of
Doors |
A special pair of doors called
double egress are not used on the exterior of a
building but are useful to separate portions of
a building, typically in a firewall application.
The doors are designed such that when approaching
them in either direction, one leaf swings in the
direction of travel. This type of application requires
use of vertical rod exit devices on both leaves.
Exterior Doors
The most frequent call for
added security is on exterior doors. The simplest,
most secure exit device application is an exit-only
door, such as the rear door of a store. This type
of exit device has no exterior trim or provision
for a key knob, thumb piece or lever. The shortcoming
of this is that the owner cannot gain entry from
the exterior.
The second-best application
would be a "night lock" function, which provides
entry, but only to those having a key. This type
of operation is similar to a storeroom function
lockset. If a higher security is required, unlocking
could be accomplished using a card or a code access
system. For a weekend and nighttime operation
the access control system could be turned off,
prohibiting entry even with a valid code. This
type of exit device could either use electric
locking of the knob set, or even better, electric
latch retraction. In this case, the exterior of
the door can be equipped with a flush cup pull,
making forced entry almost impossible.
Interior Doors
On single interior doors,
use only rim exit devices, or mortise devices
on doors equipped for that type of lockset. A
hotel or a corporate headquarters that has large
meeting rooms or ballrooms often presents a special
problem. The owner may want the doors locked at
night but unlocked, possibly with the devices
dogged, during the daytime. In most cases, however,
these doors are fire doors and mechanical dogging
is not permitted. In this case the use of electric
latch retraction is the only answer. To control
access, the latches may be hooked to a card access
system or to a remote switch. For fire doors,
the latch retraction function should be wired
to the fire alarm system so that an alarm or a
power failure will cause the doors to latch.
Related to interior applications
is the use of exit devices on vestibule doors.
These are typically nonfire doors, and dogging
is permitted. Only one of the doors in a pair
or multiple doors need be equipped with an exterior
key, typically as a night latch function. Once
the owner has entered the area, all the devices
could be mechanically dogged. For an operation
with numerous doors and where security is a high
priority, electrified latch retraction could be
incorporated. In this case the security office
could electrically dog all doors at a predetermined
opening time and then at closing time simply flip
the switch to release or relatch all the doors.
In this case no one would be locked in the building
but everyone would be locked out of the building.
Installation Pointers
One of the biggest challenges
for a locksmith or maintenance personnel, when
it comes to exit devices is installation. The
importance of using the fasteners provided by
the manufacturer cannot be overemphasized, to
ensure that all parts are stable and do not move
around. Using the correct fasteners also provides
the level of locking that the manufacturer has
tested for.
For surface-mounted hardware,
rim and surface-mounted vertical rod exit devices,
use the correct fastener or sex nuts and bolts,
as specified by the manufacturer. When mounting
surface devices on wood doors, make sure that
the door manufacturer has put in the correct reinforcement
blocking materials. Use sex nuts and bolts whenever
possible, rather than wood screws. Many times
sex bolts are necessary to meet code requirements
of the door manufacturer, particularly on wood
doors and on some steel doors. Always check with
the door manufacturer if this is not clear. When
using machine screws, it is imperative to drill
the correct size holes and use a tap where specified.
Attempting to shortcut the installation by using
self-tapping screws will always come back to haunt
the owner and possibly the installer.
When mounting a rim exit
device, be sure to use the correct backset. Whenever
possible choose a manufacturer that has an adjustable
strike to compensate for building expansion or
contraction from air conditioning, weatherstripping
and climate changes. This is especially noticeable
in dark aluminum doors on the south side of buildings,
which have been known to expand as much as 3/16"
to 1/4" in the summer sun.
When installing a cross
bar exit device, make sure that the hinge and
the lock stile cases are level, the cross bar
is cut to the correct length, and the cross bar
is installed rigidly.
When installing a touch
pad exit device, make sure that the exit device
clears any glass beads that may extend past the
surface of the door. The glass bead is the little
rim that goes around a window, also called a light.
Kits are available to shim the device away from
the door surface.
When installing vertical
rod devices, make sure that the vertical rods
are perpendicular to the exit device to prevent
binding. Also, make sure that the rods are in
line with the top and bottom latch. Read the manufacturer’s
installation instructions carefully before cutting
the vertical rods to length. In most cases, only
the top rod should be cut. It is also helpful
to understand how the vertical rod exit device
works. In many cases the top latch controls the
operation of the bottom latch. This will be covered
in the manufacturer’s installation manual.
When using the vertical
rod exit devices, it is imperative that both rods
be used. If both rods are not used on a fire device,
the fire label will be voided. For security purposes,
if both rods are not used, the door is an easy
entry point.
One of the most common mistakes
when installing vertical rod exit devices is to
interchange the top and bottom latch cases. When
unpacking a vertical rod device, carefully examine
both of the latches and make sure that they are
not mixed up.
Earlier we mentioned the
term astragal. An astragal is simply an overlapping
wood or metal part that is attached to the face
of one door to either help protect doors in need
of fire label or to prevent entry of weather,
sound, or light. If a pair of doors is equipped
with an astragal, do not use two vertical rod
exit devices. It is also critical to know which
door must be opened first and equip it with a
rim or mortise lock set.
This door is referred to
as the active leaf of the pair of doors. The inactive
or second leaf is the one that is equipped with
the vertical rod exit device. On pairs of doors
that must close in a particular sequence, the
use of a coordinator is required. The coordinator
prevents the active leaf from closing before the
inactive leaf has closed. A carry bar is sometimes
used with a coordinator, to open the active leaf
if the inactive leaf is opened first by mistake.
Regardless of the type of
lockset, vertical rod, rim device or other hardware
that has been selected, it should be combined
with a good quality closer to assure continued
satisfactory operation of the hardware. While
this article does not deal with door closers specifically,
it is important to realize that if a bargain-priced
door closer is put on an expensive pair of doors
with expensive hardware, it will probably destroy
the door and the hardware that is mounted on it
rather quickly. For exterior doors that are exposed
to windy conditions or heavy usage, an overhead
stop is also a requirement.
This information is intended
to provide a better insight into the use of exit
devices and provide some facts to work with when
servicing, replacing or inspecting them. The overall
goal should be to secure a building while not
violating any life safety or fire codes.
Command Terms
and References
Code Officials
and Testing Laboratories
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