UFC 4-021-02NF
27 September 2006
change 1, 23 October 2006
These doors need to be keyed such that they can be manually unlocked by appropriate
response personnel until the security alarm panel and electrical power can be reset.
Emergency doors are required to be able to be opened for exiting during a fire-
emergency except for certain restricted institutional facilities (prisons and high-security
hospitals).
9-4.6.3 Door Coordination. Door control impacts (door hardware needs or changes)
are sometimes overlooked in project construction cost estimates. Inventory of doors
and assessment of door and hardware suitability should be an early design issue for
assessing project door interface requirements. Door coordination is one of the most
frequent (and costly) problem areas on security projects. It is important that the ESS
designer coordinate with the project architect to ensure that the proper door hardware is
specified and installed.
9-4.6.4 Life Safety Codes. Great care should be taken in designing access control
for doors. Refer to the Life Safety Code and Means for Egress for Buildings and
Structures for code guidance on egress and ingress doors.
9-4.6.5 Recommendation. Unless there is a compelling convenience reason for
making a door fail-safe, most ESS projects are designed such that the door hardware is
Fail-Secure.
9-4.7
Door Locks
9-4.7.1 Electric locks. The electric lock is a very secure method to control a door. An
electric lock actuates the door bolt. For very secure applications dual locks can be used
(for example, a retractable bolt on and at the top of the door frame and an additional
retractable bolt on the side of the door). In some cases, power is applied to engage the
handle, so the user can retract the bolt vice the electric operator actually retracting the
bolt. Most electric locks can have built-in position switches and request-to-exit
hardware. While offering a high security level, electric locks carry a cost premium. A
special door hinge, that can accommodate a wiring harness and internal hardware to
the door, is required. For retrofit applications, electric locks usually require purchase of
a new door.
9-4.7.2 Electric strikes. The difference between an electric strike and an electric lock
is the mechanism that is activated at the door. In an electric-lock door the bolt is moved.
In an electric-strike door the bolt remains stationary and the strike (or cover latch) is
retracted. As in electric locks, electric strikes can be configured for fail-safe or fail-
secure operation. The logic is the same. In fail-safe configuration the strike retracts
when de-energized on loss of power. This allows the door to be opened from the public
side. In fail-secure configuration the strike remains in place causing the door to be
locked from the public side and requires manual key entry to unlock the door from the
public side. Again, as with electric locks, unimpeded access is allowed for in the
direction of egress by manual activation of the door handle/lever when exiting from the
secure side. For retrofit situations electric strikes rarely require door replacement and
can often be done without replacing the doorframe.
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