Access control applications
3.18 EST3 Installation and Service Manual
Delayed egress
Description of the application
Delayed egress doors help to control shoplifting at retail sites. A
delayed egress door has card readers and a request to exit (REX)
switch. Employees can badge in and out as they would at any
other door. In an emergency, customers must press the REX
switch to unlock the door.
When the REX switch is activated, the CRC sounds the
CRCSND horn and sends a security alarm event to the panel. It
does not unlock the door immediately, thus allowing site staff
time to investigate.
The CRC waits for a specific interval of time before unlocking
the door. The typical delay time is 15 seconds; however, you
may be able to use a delay of up to 30 seconds with the approval
of the AHJ. The horn continues to sound for a specific period of
time, or until the CRC is reset.
After the delay time passes, the CRC unlocks the door, and
latches it in the unlocked state. The CRC must be reset in order
to relock the door and silence the horn. To reset the CRC, site
staff must use a valid badge at the card reader.
The CRC also activates the CRCSND horn if the door is opened
without badging. For example, if the door is forced open from
the outside, the CRCSND activates, even though the REX switch
has not been pressed.
Many codes require that delayed egress doors unlock during a
fire alarm, or when the panel is in trouble. This requirement
allows occupants to evacuate the site immediately when a fire is
detected, or when the panel loses its ability to detect a fire or
sound the alarm.
Figure 3-5 shows a delayed egress door with inside and outside
card readers and a request to exit switch. The CRC uses a door
contact switch to determine the position of the door, and a
maglock to lock the door. The door contact switch and REX
switch are connected to the input loops of the CRC.
Note: Refer to NFPA 101 and the local AHJ to determine the
requirements for delayed egress applications.
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