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Part
1 - What is an Exit Device?
An
exit device facilitates exit through an opening. According to
ANSI 156.3 Section 2.6.4, an exit device is a door latching assembly
incorporating an actuating mechanism usually called an activating
bar which releases latch bolt(s) upon application of forces in direction
of travel. It is important to remember that exit devices
should not be called push bars (this speaks to the action, not the
purpose), crash bars (a slang term) or panic bars (suggests a negative
connotation).
The Purpose of an Exit Device
There are several reasons to use an exit device. They
provide safe emergency egress (exit) from a building. They
also allow barrier free access, and comply with the ADA and ANSI
117.1. Furthermore, exit devices encourage increased security with
authorized entrance features and fail safe exit designs. They also
contain fire and smoke through compartmentalization.
Buildings require exit devices to comply
with both fire and life safety codes (NFPA 80, NFPA 101) and building
codes (IBC, BOCA, SBC). While these codes offer guidelines, the
local authority with jurisdiction has the final word.
Where to Use an Exit Device
Exit devices are used on doors that must be latched and provide
an exit in emergencies. Examples of this include stairwell doors,
cross corridor doors, exit doors and exit only doors.
There are three situations in which exit
devices should always be used. These include:
- High occupancy areas, where there is a
concern for exiting in an emergency
- Perimeter security, where there is a restricted,
authorized entrance with provisions for exit under alarm conditions
- Security systems, where there is a need
for access control
Critical
Selection Issues
There are five major issues to consider
when selecting an exit device:
- First, you must know whether or not a
door is listed or labeled (meaning it has been tested and approved
by an authorized agency). This consideration includes panic doors,
which are approved for use on "non-fire listed" doors
in the emergency path of egress, and fire doors, which are approved
for use on "fire listed" doors in the emergency path
of egress.
- Next, you must understand the door stile
width, or vertical member of the door structure. A wide or medium
stile is used when the vertical member on the latch or pivot side
edges will accept narrow, medium, or wide stile devices. A narrow
stile, on the other hand, is used when the vertical member on
latch or pivot side edges requires use of narrow stile device.
- Third, you must analyze traffic control
and people flow, including traffic volume (based upon building
type and occupancy) as well as the entrance and exit.
- Fourth, the electronic interface must
be considered. This includes security, or authorized entrance
and fail safe exit, monitoring of the door, access control relative
to both the ingress and egress, and the fire/smoke control system.
- Lastly, you must account for accessibility.
A barrier free environment adheres to the ADA and ANSI 117.1 in
terms of levers (versus knobs) and the absence of thumb operated
trim.
Exit Device Types and Styles
There are six types of exit devices. The
crossbar can
not be chained and is not very secure while the paddle is
generally limited to hospital applications. The full length touchpad features
an operating mechanism as long as the device. The partial length
touchpad, on
the other hand, is at least ½ of the door's length and permits
field retrofit (alarmed exit, cylinder dogging). A flush panel in
the door is typically the most difficult to prepare and install
as the door must be specifically prepared to show only the touchpad.
Lastly, electronic control features
electrified options. This includes monitoring the door status with
alarmed exits and controlling the entrance and exit with delayed
egress, among others.
Exit devices are available in three styles:
- First, the medium/wide style device features
a larger chassis and cover, requires larger stiles for reinforcement
and is common in commercial buildings.
- Second, the narrow style device is aesthetically
pleasing, has a thinner chassis, and accommodates narrow stile
doors and is commonly used on aluminum doors.
- Lastly, the standard style device is less
expensive, but has limited applications and finishes.
Applications
Exit devices have four primary applications.
When used with a rim device, there
is a single latch point. As a result, the components are surface
applied, allowing for simple application, preparation and installation.
Next, the surface vertical rod requires
two latch points (at both the top and bottom) and therefore involves
more components. The concealed vertical rod is very similar
to the surface vertical rod. It involves two latch points (at the
bolt and rod). It is more difficult to prepare, install and adjust
as assembly is concealed in the door. Lastly, the mortise
device features a single latch point. It uses a mortise lock, operated
by the exit device, and requires a mortise in the door for the lock
body.
Evaluation
Upon submission, results of
your evaluation will be displayed with the correct answers shown
in red.
-
Exit devices can also be referred to as push bars, crash bars or panic bars.
Yes
No
-
Who has final say over exit device compliance?
NFPA 80, NFPA 101 fire and safety codes
Local authority with jurisdiction
IBC, BOCA, SBC building codes
-
Which situation offers restricted, authorized entrance under alarm conditions?
Perimeter security
Low occupancy areas
Court yards
-
Which one of the following meets the criteria for selecting an exit device?
Listed or labeled doors
Traffic flow
Electronic interface
All of the above
-
The following style of exit device is more common in commercial buildings:
Narrow
Standard
Medium/Wide
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