Building Security
Exit
Locks
Exit locks, sometimes referred to as exit control
devices, are listed in the UL “Mechanical Equipment
Directory” under the heading FQUV. While these devices
may look like exit devices, they may or may not
be approved as panic hardware or fire exit hardware.
There are several types of devices available for
exit control, including:
- a. Hardware that permits
exiting and sounds an alarm.
- b. Hardware that delays
egress for a designated period of time and sounds
an alarm.
- c. Hardware that qualifies
as panic hardware or fire exit hardware, in
addition to sounding an alarm. While this may
appear confusing, the first two types are not
always approved for use or do not qualify as
panic or fire exit hardware.
Unfortunately, exit locks are
sometimes installed on doors that require either
panic or fire exit hardware. While this may be from
ignorance of code requirements or lack of thought
when a building owner requests alarmed devices,
the consequences cannot be overstressed. Improper
selection may place more than one party in jeopardy
and lead to expensive legal consequences.
It should be noted that
some manufacturers can add an alarm package to
an existing exit device without replacing the
entire unit.
Special Locking Arrangements
This type of hardware permits delayed egress for
up to 15 seconds. Once the device is activated,
it starts an irreversible sequence of events that
includes sounding an alarm for the specified period
before allowing exiting to occur. The use of this
hardware has specific restrictions regarding delay
of egress and is limited to specific occupancies.
Table III shows variations and limitations of
the model building codes.
The UBC is obviously more
stringent than the other codes, as it limits occupancy
essentially to businesses and requires both sprinklers
and smoke detectors throughout the premises.
Table
III
|
| Code |
Permitted Occupancy |
Remarks |
|
BOCA
[Sec. 813.4.1.2] |
Business
Factory & Industrial
Institutional
Mercantile
Storage
Residential
|
Automatic sprinklers
or smoke detectors throughout building.
|
|
SBC
[Sec. 1113.6] |
All Occupancies
except Assembly |
Automatic sprinklers
or smoke detectors throughout building. |
|
UBC
[Sec. 3304(e)] |
B-2 Occupancies
(See Note 1) |
Automatic sprinklers
and smoke detectors throughout building. |
|
LSC
[5-2.1.6] |
Assembly, except
main entrance
Educational
Health Care (See Note 2)
Hotels & Dormitories
Apartments
Lodging & Rooming Houses
Mercantile
Business
Industrial
Storage |
Automatic sprinklers
or smoke detectors throughout building. |
|
Note 1: B-2 includes
drink & dining establishments with occupant load
less than 50, wholesale & retail stores, office
buildings, printing plants, police & fire stations,
factories & workshops using materials not highly
flammable or combustible, storage and sales rooms
for combustible goods, paint stores without bulk
handling, buildings or portions thereof used for
education beyond 12th grade with less than 50 occupants
in any room.
Note 2: Health care
allows only one device within any path of egress.
Deadlocking
This feature is valuable in preventing the latchbolt
from being forced out of the strike by manipulation.
Some manufacturers offer this feature on all exit
devices, while others limit it to specific devices.
Deadlocking may not be as important on rim devices,
since the latchbolt is safeguarded because the
strike is mounted on the face of the frame stop.
In determining whether it is needed for a particular
door, consider the door’s location and the level
of security desired.
Dogging
Holding the latchbolt in the retracted position
is termed dogging and is permitted only on devices
that are not fire-rated. Dogging may be achieved
through the use of a tool or a key cylinder, depending
on the design of the exit device. Cylinder dogging
is considered to be more secure, as a dogging
tool is too easy for unauthorized persons to obtain.
Switches
Switches may be used with exit devices for a variety
of purposes. A signal switch can monitor the position
of a pushpad or latchbolt. Other switches may
be used on doors that have door status indicator,
as a request-to-exit signal to allow egress without
sending an alarm.
Auxiliary Locks and Exit
Devices
Auxiliary locking mechanisms or devices, which
prevent full use of panic hardware or fire exit
hardware, are not permitted. This is specifically
referenced in LSC 5-2.1.5.5 and inferred by other
model codes, although they do not refer to it
specifically.
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