Codes Apply for Electromagnetic Locks
An
electromagnetic lock (EM Lock) is essentially an electromagnet in a housing
mounted on the door frame, and a steel armature mounted on the door wing. When
the magnet is energized, it bonds to the armature and locks the door. To allow
access or egress, a switch must be provided to de-energize the electromagnet. It
can be difficult to determine which set of code requirements to follow.
However, code compliance is crucial when this product is used in an access- or
egress-control system. Unlike most locks, electromagnetic locks typically require
external release devices such as motion sensors or request-to-exit switches to
allow building occupants to exit. In addition, secondary means of releasing the
mag-lock are often mandated by the codes, and the requirements vary depending
on the type of locking system used.
Prior
to the 2009 edition of the International Building Code (IBC), the set of code
requirements typically used for doors equipped with electromagnetic locks was
the section called Access-Controlled Egress Doors. The 2009 edition added a
second set of requirements that could be used, called Electromagnetically
Locked Egress Doors. Either of these two sets of requirements can now be used,
depending on the application.
The
basic difference between these two sections is that the original section,
Access-Controlled Egress Doors, required a sensor and push button as release
devices, while the new section, Electromagnetically Locked Egress Doors, allows
a door-mounted release device instead. This could be panic hardware or a
latchset with a request-to-exit (RX) switch, or a bar with an electronic touch
sensor.
A
building could have several AHJs (Authorities Having Jurisdiction), and more
than one code may be enforced for a particular project. The most commonly used
model codes in the U.S. are the International Building Code (IBC), the
International Fire Code (IFC), and NFPA 101 – The Life Safety Code, but state
and local codes sometimes include modifications that affect the use of
electrified hardware. It’s usually best to follow the most stringent set of
requirements that have been adopted in the project’s jurisdiction.
Here
is a summary of the requirements for both sections from the 2009 IBC:
1008.1.4.4 Access-Controlled Egress
Doors
·
Applies
to entrance doors in a means of egress and entrance doors to tenant spaces.
·
Allowed
in Use Groups - A (Assembly), B (Business), E (Educational), I-2 (Institutional
- Hospitals & Nursing Homes), M (Mercantile), R-1 (Residential - Hotels,
Motels, & Boarding Houses), and R-2 (Residential - Apartments & Dormitories).
·
A
sensor must be mounted on the egress side to detect an occupant approaching the
doors. Doors must unlock upon a signal from the sensor or loss of power to the
sensor.
·
Loss
of power to the lock must unlock the doors.
·
A
manual unlocking device (push button) shall result in direct interruption of
power to the lock – independent of the access control system electronics. When
the push button is actuated, the doors must remain unlocked for 30 seconds
minimum. The push button must include signage stating “Push to Exit” and must
be located 40” to 48” vertically above the floor and within 5’ of the doors.
Ready access must be provided to the push button.
·
If
the building has a fire alarm/sprinkler system/fire detection system,
activation of the system must automatically unlock the doors. Doors must remain
unlocked until the system has been reset.
·
Entrance
doors in buildings with an occupancy in Group A, B, E or M shall not be secured
from the egress side during periods that the building is open to the general
public.
1008.1.9.8 Electromagnetically Locked
Egress Doors
· Applies
to doors in a means of egress and doors to tenant spaces. The 2009 IBC includes
a limitation to doors “not otherwise required to have panic hardware,” which
was removed in the 2012 edition.
·
Allowed
in Use Groups - A (Assembly), B (Business), E (Educational), M (Mercantile),
R-1 (Residential - Hotels, Motels, & Boarding Houses), and R-2 (Residential
- Apartments & Dormitories).
· The
door must be equipped with listed hardware mounted on the door leaf, which
incorporates a built-in switch to directly release the electromagnetic lock and
unlock the door immediately.
· The
release device must have an obvious method of operation, and must be readily
operated with one hand under all lighting conditions.
· Loss
of power to the listed hardware must automatically unlock the door.
· When
the new section was added to the 2009 IBC, the technical committee made a
change to the proposed language which caused some confusion. A limitation to
doors that are “not otherwise required to have panic hardware” was
included in the 2009 edition, but it appears that this was not the intent. The
limitation was removed and the intent clarified in the 2012 edition of the IBC,
and as long as the switch in the panic bar releases the mag-lock, a door
required to have panic hardware can be equipped with a mag-lock.
·
With
the addition of Section 1008.1.9.8 – Electromagnetically Locked Egress Doors,
the door-mounted release device can be used instead of the sensor and emergency
push button. Note that this section does not require the mag-lock to release
upon activation of the fire alarm or sprinkler system when a door-mounted
release device is used. But there are a few issues that are still unclear, even
with the 2012 changes.
· The
door must unlock upon loss of power to the “listed hardware,” which in this
case is the door-mounted release device. Loss of power to some types of
request-to-exit switches will not unlock the mag-lock. We may see a future
change to the language so that loss of power to the electromagnetic lock is
required to unlock the door, but the code currently addresses the release
device.
·
I-2
occupancies (Institutional – Hospitals & Nursing Homes) are not included as
acceptable locations for electromagnetically locked egress doors. This use
group was added to the Access-Controlled Egress Doors section in the 2009
edition of the IBC, so hopefully the new section will catch up and include the
I-2 use group in the future.
·
UL
305, the UL Standard for Panic Hardware, doesn’t address the use of panic
hardware to release an electromagnetic lock. There is also a section of the IBC
which states that certain doors shall not be equipped with a latch or lock
unless it’s panic hardware. This should be changed to reflect the use of a mag-lock
released by panic hardware.
The following summaries address each type of
system where a mag-lock might be used, and the related model code requirements:
Sensor Release: A sensor automatically unlocks the electromagnetic lock
to allow egress.
This is the most common type of system where
electromagnetic locks are used. In past editions of the model codes, the
applicable section referred to “access-controlled egress doors” which often
gave the impression that the requirements applied to all doors with an access
control system. A typical access control system which controls access but
utilizes a lever handle or panic hardware to allow free egress is not required
to comply with this section. The intent is for this section to apply only to
electrified locks that are released by a sensor, and the title of this section
has been changed in the model codes to clarify the intent.
For these systems, a sensor on the egress
side of the door opening must detect an approaching occupant and unlock the
door. The door must also unlock upon loss of power to the sensor or locking
system, upon activation of the building fire alarm or automatic sprinkler
system (until manually reset), and upon actuation of an auxiliary switch –
typically a push button. This switch must be located 40-48 inches above the
floor and within 5 feet of the door, must be readily accessible, and must be
marked “PUSH TO EXIT.” Pushing the button must directly interrupt power to the
lock, independent of the other electronics, and the door must remain unlocked
for at least 30 seconds.
Recent editions of the IBC/IFC and NFPA 101
include virtually identical egress requirements for these systems, and all of
these model codes currently require the UL 294 listing for these applications.
It’s important to note that when this type of system is installed on a door
that is required by code to have panic hardware, the panic hardware is required
in addition to the electromagnetic lock.
Door-Hardware Release: A switch in the door-mounted hardware releases
the electromagnetic lock to allow egress.
This type of system typically utilizes a
request-to-exit (RX or REX) switch in the lever handle, panic hardware, or
sensor bar mounted on the door. Again, the requirements of the IBC/IFC and NFPA
101 are very similar. The model codes require the hardware mounted on the door
to have an obvious method of operation, and to be readily operable with one
hand and under all lighting conditions. Operation of this door-mounted hardware
must directly interrupt power to the electromagnetic lock, and the door must
unlock immediately. The door must also unlock upon loss of power to the locking
system, and the UL 294 listing is required by the current model codes. Note
that this section does not require an auxiliary push button beside the door, or
for the door to unlock upon activation of the fire protection system, although
some local codes or AHJs may mandate these additional safety overrides.
Delayed Egress: Doors are locked to delay egress for 15 seconds under
normal operation but allow immediate egress during an emergency.
There are two types of egress:
·
Free means that someone can exit an egress door without any delay by
using only a single motion, such as turning a lever or pushing on a panic bar.
·
Delayed means that there’s a timed delay before someone can pass through the
egress door and exit. Typically, this delay is 15 seconds.
Delayed egress is used to:
·
Discourage casual use of
certain doors, so pedestrians can’t leave a premises or steal merchandise.
·
Deter elopement of patients,
children or inmates from a protected area of a facility.
·
Make possible access
control in both directions through selected openings.
Often, delayed egress systems include panic
hardware with delayed egress circuitry, but electromagnetic locks are also available
with this function. The lock includes an integral timer which allows the door
to be opened 15 seconds after an attempt to exit is made – or 30 seconds when
approved by the AHJ. The activation switch may be part of the mag-lock, or the
timer may be initiated by an external RX switch.
To ensure free egress in an emergency,
delayed egress locks must unlock immediately (no 15-second delay) upon
activation of the fire protection system or sprinkler system, and upon loss of
power. The capability of allowing immediate egress by a switch at the fire
command center or other location may also be required.
Under normal operation, the delayed egress
lock prevents egress until a force of 15 pounds, maximum, is applied for not
more than 3 seconds; an audible alarm will sound in the vicinity of the door,
and in 15 seconds the door will unlock to allow egress. After the device has
been released by an attempt to exit, it must be rearmed manually - current
codes do not allow delayed egress locks to rearm automatically.
Doors with delayed egress locks must also
include signage stating, “PUSH UNTIL
ALARM SOUNDS. DOOR CAN BE OPENED IN 15 SECONDS.” When a delayed egress lock
is installed on an inswinging door, or when an AHJ approves a 30-second time
delay, the signage must reflect the applicable operation. Specific requirements
for the signage can be found in the model codes, and current codes also require
the UL 294 listing for delayed egress locking systems.
The model codes include some additional
limitations based on the use group or occupancy classification. For example,
past editions of the IBC/IFC prohibited the use of delayed egress locks in
assembly, educational, and high hazard occupancies, but the 2018 editions
include exceptions for doors serving classrooms with an occupant load of less
than 50 people, and for secondary exits from courtrooms. Delayed egress locks
are allowed in those locations when the jurisdiction has adopted the 2018
edition of the model code, or when approve by the AHJ.
Controlled Egress: In health care facilities where patients require
containment for their safety or security, doors may be locked in the direction
of egress under normal operation but must allow emergency egress.
The IBC and IFC allow this application to be
used in some health care units in hospitals, nursing homes, and other Group I-1
and I-2 facilities. These units might include memory care, maternity,
pediatrics, or other areas approved by the AHJ. NFPA 101 includes these
requirements in the chapters that cover new and existing health care
facilities, and the code allows the doors to be locked where patients’ special
needs require specialized protective measures for their safety or security.
According to the IBC and IFC, the building
must have an automatic sprinkler system or automatic fire detection system, and
activation of these systems must unlock the doors to allow egress. Loss of
power must also automatically unlock the controlled egress doors, as well as a
switch that directly breaks power to the lock - located at the fire command
center, nurses station, or other approved location. A building occupant must
not be required to pass through more than one door equipped with a controlled
egress lock before entering an exit. The automatic-release requirements listed
here do not apply to areas used for psychiatric treatment, or hospital units
where listed infant abduction systems are installed.
All clinical staff members must have the
ability – including keys or credentials – to unlock the doors for emergency
egress, and these procedures must be included in the facility’s emergency plan.
Training and drills are crucial in order for staff to be familiar with the
egress protocols. Systems used for controlled egress must be listed to UL 294,
and emergency lighting must be present at doors equipped with these locks. The
requirements of NFPA 101 would not change the type of locks used in these
systems (fail safe electrified locks), but the Life Safety Code does include
slight variations to the required safety systems and procedures.
Stairwell Reentry: Stairway access doors may be locked on the stair side
but must unlock to allow building occupants to leave the stairwell if it
becomes compromised during a fire.
The IBC and IFC require all stairwell doors
that are lockable on the stair side to have electrified locks that can be
remotely released by a switch at the fire command center, or other approved
location. (Note: Stair discharge doors may be locked to prevent access to the
stairwell but must allow free egress.) For high-rise buildings, the IBC and IFC
require the stairwell to be equipped with a two-way communication system if
doors are electrically locked. Consult the IBC/IFC for exceptions related to
buildings with a single exit stair.
The NFPA 101 requirements for stairwell
reentry differ from the IBC and IFC, so it’s very important to refer to the
adopted code to verify what is required. For example, NFPA 101 allows doors to
be mechanically locked on the stair side when serving four stories or less –
the IBC and IFC require these doors to be electrically locked, or never locked.
NFPA 101 also exempts some occupancies from the reentry requirements, and
includes a section detailing the criteria for “selected reentry” – which allows
some doors to be mechanically locked and others to allow reentry.
If mag-locks are used on fire-rated stair
doors, the door must be equipped with additional latching hardware to maintain
the fire rating. In addition, the mag-locks must meet the applicable
requirements on the egress side – sensor release, door hardware release,
delayed egress, or controlled egress. Fail-safe electrified locks or fail-safe
trim for fire exit hardware is commonly used; fail safe electric strikes are
not listed for use on fire door assemblies.
Elevator Lobby Egress: Doors secure the elevator lobby and prevent
access to the tenant space but must allow emergency egress from the lobby.
Currently, the IBC and IFC require each
elevator lobby to have code-compliant egress via at least one exit. This could
include direct access from the lobby to an exit stairwell, or free egress from
the lobby to a corridor that leads through a tenant space to an exit. This
means of egress must not be restricted, except with a delayed egress lock (most
occupancy types) or an exit alarm.
NFPA 101 does allow egress through elevator
lobby doors to be restricted during normal operation, if the doors allow
emergency egress. The application must be allowed by the applicable occupancy
chapter. For example, Chapter 11 (Special Structures and High-Rise Buildings)
allows elevator lobby exit access doors to be locked “in other than newly
constructed high-rise buildings.” Therefore, this application would not be
allowed by NFPA 101 in new high-rise buildings.
The building must have a fire alarm and
sprinkler system, and the lobby must have a smoke detection system. Activation
of any of these systems (except by manual pull stations), or loss of power must
automatically unlock the doors to allow egress. The doors must remain unlocked
until the system is manually reset.
The elevator lobby must have a two-way
communication system connected to a central control point that is constantly
staffed by people who can provide emergency assistance. The electrified hardware
must be listed to UL 294, and any latch-releasing hardware on the door must
comply with the egress requirements of NFPA 101.
Because the IBC and IFC do not include a
section similar to NFPA 101 regarding elevator lobby doors, some cities and
states have modified the IBC/IFC to allow these doors to be electrically
locked. These modifications typically require fail safe locks which unlock
automatically upon activation of the fire protection system, as well as
communication between the elevator lobby and a security desk or other location.
Security Interlock: Two or more doors are interlocked so that when one
door is opened, the other door cannot be opened; commonly used on clean rooms
and high-security applications.
Mag-locks are often used in security
interlocks, but this application is not currently addressed in the model codes
except when related to a prison sallyport. This type of system could impede
egress, so each application must be approved by the AHJ, and additional safety
features may be required. For example, to avoid entrapment in the room or
vestibule, the AHJ may require emergency override switches in both locations,
as well as an override switch on the exterior that is controlled by a key or
credential. These switches will allow the doors to be unlocked for access or
egress if one door is in the open position, preventing the use of the other
door. In most security interlocks, the locks are automatically unlocked upon
activation of the fire protection system, to allow free egress. Consult the AHJ
to determine what is required.
In most cases, only one of these sections
will apply to a particular door opening equipped with a mag-lock. The exception
would be a stairwell door that must meet the stairwell reentry requirements on
the stair side but would have one of the other applications on the egress side.
Remember, refer to the applicable model codes and any state or city
modifications to determine whether additional limitations apply, and consult
the AHJ if more information is needed.
Code Comparisons - Occupancy Classifications
I-Codes. Until
the 2018 edition of the IBC, delayed-egress locks were allowed in all use
groups except A – assembly, E – educational and H – high hazard. Beginning with
the 2018 edition, delayed-egress locks are allowed on the secondary exits that
serve courtrooms (typically assembly occupancies) if the building has a
sprinkler system. The 2018 edition also allows delayed-egress locks on
classroom doors in educational occupancies if the calculated occupant load
served by the door is fewer than 50 people. This gives schools an option if
they’re looking for a way to prevent elopement of young children or students
who have special needs.
NFPA. The
NFPA codes are less restrictive and allow delayed-egress locks in areas of low
and ordinary hazard contents, although the Life Safety Code includes
restrictions depending on the occupancy. For example, delayed-egress locks
aren’t permitted on the main entrance or exit doors that serve assembly occupancies,
and they also are prohibited on airport jetway doors. Lodging or rooming houses
can have only one door that has a delayed-egress lock per escape path, and
residential board and care facilities are permitted to have delayed-egress
locks only on exterior doors. The other occupancy classifications aren’t
subject to similar limitations.
Code Comparisons - Required Fire Protection System
I-Codes & NFPA. Both sets of
model codes require buildings that have delayed-egress locks to be equipped
throughout with an automatic sprinkler system or approved automatic smoke- or
heat-detection system. This requirement allows either type of system, although
the change to the 2018 IBC that applies to courtrooms specifically requires a
sprinkler system.
Code Comparisons - Activation Time
I-Codes & NFPA. Both sets of
model codes require the delayed-egress timer to begin when a force of 15 pounds
is applied for no more than 3 seconds. Prior to the 2015 edition of the IBC,
the timer was required to begin after someone attempted to exit for 1 second.
The activation time required to initiate the 15-second (or 30 second) timer is
permitted to be less than 3 seconds, but it can’t be more than 3 seconds.
Code Comparisons - Automatic Release Delay
I-Codes & NFPA. When the timer
is activated, the model codes require the delayed-egress lock to release in the
direction of egress after 15 seconds; the AHJ might approve a time delay of 30
seconds. After that period, the door will be unlocked in the direction of
egress, and another attempt to exit will allow the door to be opened.
Code Comparisons - Rearming After Activation
I-Codes & NFPA. When the timer
of a delayed-egress lock is activated and the lock allows egress after 15 (or
30) seconds, the model codes require the lock to be rearmed manually.
Code Comparisons - Audible Alarm
I-Codes & NFPA. Both sets of
model codes require an audible alarm to sound when a delayed-egress lock is
activated, but the codes don’t mandate a specific type of alarm. Some products
incorporate a continuous alarm, while others have an intermittent sound or even
a verbal countdown.
Code Comparisons - Signage Requirements
I-Codes. Signage
must state "PUSH [PULL] UNTIL ALARM SOUNDS. DOOR CAN BE OPENED IN 15 [30]
SECONDS.” These signs are required for doors equipped with delayed-egress locks
(see exception for Group I) and must be mounted above and within 12 inches of
the door exit hardware. Beginning with the 2015 edition, signage is required to
comply with the visual character requirements of ICC A117.1 – Accessible and
Usable Buildings and Facilities. In Group I – institutional occupancies, the
AHJ may allow signage to be omitted for certain types of treatment areas.
NFPA. The
required text for the signage is the same as that required by the I-Codes:
“PUSH [PULL] UNTIL ALARM SOUNDS. DOOR CAN BE OPENED IN 15 [30] SECONDS.” The
NFPA codes require signage for delayed-egress locks to be readily visible, with
letters not less than 1 inch high, a stroke width of one-eighths of an inch and
a contrasting background, durable and located on the egress side of the door
adjacent to the release device.
Code Comparisons - Action Upon Alarm Activation
I-Codes. When
the fire alarm or sprinkler system is activated, delayed-egress locks must
allow immediate egress automatically. This ensures that building occupants can
exit quickly during a fire.
NFPA. The
NFPA codes are more specific regarding the types of system activation that must
unlock the delayed-egress locks for emergency egress. These doors must unlock
with no delay in the direction of egress upon the activation of a sprinkler
system, not more than one heat detector or not more than two smoke detectors.
Code Comparisons - Remote Release
I-Codes. To
allow immediate egress when necessary, the I-Codes require delayed-egress locks
to be capable of being deactivated by a switch at the fire command center or
other approved locations.
NFPA. Remote
release isn’t mandated by the section of the Life Safety Code that addresses
delayed-egress locks.
Code Comparisons - Action Upon Power Failure
I-Codes & NFPA. When power
fails, both sets of codes require delayed-egress locks to unlock immediately in
the direction of egress. A common question about delayed-egress locking systems
is whether battery backup is allowed in the power supply of the electrified
hardware. The model codes don’t address this specifically, so it often is left
up to the AHJ to decide whether delayed-egress locks must release upon loss of
the main power to the building or continue to delay egress on standby power.
However, based on the requirements of NFPA 72 – National Fire Alarm &
Signaling Code, I don’t recommend using independent battery backup in the power
supply of the delayed-egress lock. If the fire-alarm system and delayed-egress
locks are powered by two different standby power systems, the hardware might
not interface properly with the fire alarm after the loss of main building
power. Using the same standby power source for the fire-alarm system and
delayed-egress locks is preferred.
Code Comparisons - Emergency Lighting
I-Codes & NFPA. Emergency
lighting is required by both sets of model codes, on the egress side of the
door on which a delayed-egress lock has been installed. It’s important to check
for the presence of emergency lighting before you install delayed-egress
hardware.
Code Comparisons - Quantity of Locks per Egress Path
I-Codes. For
most use groups, only one delayed-egress lock is allowed per egress path. This
has changed from past editions of the I-Codes, where a building occupant could
encounter only one delayed-egress lock before going through an exit. In Group I
– institutional occupancies, such as hospitals, nursing homes and day care
facilities, the I-Codes allow two doors that have delayed-egress locks per egress
path, with a maximum combined delay of 30 seconds. In Group I-1, Condition 1
and Group I-4, the exception permitting two doors that have delayed-egress
locks mandates that the building is equipped with a sprinkler system
throughout.
NFPA. For
most occupancy classifications, the NFPA codes don’t restrict the number of
delayed-egress locks per egress path. Only in lodging or rooming houses does
the Life Safety Code limit delayed-egress locks to one device per escape path.
Required Listings
I-Codes & NFPA. Both sets of model codes
require delayed-egress locking systems to be listed to UL 294 – Standard for
Access Control System Units. If a delayed-egress lock will be installed on a
fire-door assembly, it also must be listed to UL 10C – Positive Pressure Fire
Tests of Door Assemblies or NFPA 252 – Standard Methods of Fire Tests of Door
Assemblies. In addition to the other listings, panic hardware that has delayed
egress as a feature must be listed to UL 305 – Standard for Panic Hardware
(I-Codes & NFPA) and in some cases BHMA A156.3 – Exit Devices (NFPA only).
If you are
a system integrator or access automation installer or even a distributor, it is
important to know how to select the best code application for access system on
behalf of the customer. Majority of the datasheets and catalogues are not
really useful unless you already know what you are getting into. If need any
further information contact us on ssaintegrate@gmail.com.
Further Reading
For more on codes and delayed-egress locks:
IBC sections for Delayed Egress:
·
2021 – 1010.2.13
·
2018 – 1010.1.9.8
·
2015 – 1010.1.9.7
·
2012 – 1008.1.9.7
·
2009 – 1008.1.9.7
NFPA 101 sections for Delayed Egress Electrical Locking systems:
7.2.1.6.1
