I’m working on another whiteboard animation video to help explain the different code sections that apply to mag-locks. These sections have often been misinterpreted in the past. The draft of the script for this video is below, and I’d love some feedback. Did I forget anything?
Decoded: Code Requirements for Electromagnetic Locks [Draft Script]
An electromagnetic lock is essentially an electromagnet in a housing that is mounted on the door frame, and a steel armature mounted on the door. 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 magnet.
There are two sets of requirements included in the model codes that are typically applied to electromagnetic locks. These sections address two different applications, so for each mag-lock installation, one set of requirements must be followed (not both).
The two applications addressed by the model codes are:
- An electrified lock released by a sensor that detects an occupant approaching the door and unlocks the door, or
- An electrified lock released by door-mounted hardware that incorporates a switch to immediately release the lock for egress.
When discussing these applications, the words “electromagnetic lock,” “electrically-locked,” and “electrified lock” may be used, but the important thing to remember is that these code sections apply to electrified locks that are unlocked by a sensor, or by a switch in door-mounted hardware. The most common type of lock used in these installations is an electromagnetic lock.
In the International Building Code, the sections that apply to these applications are:
- Sensor Release of Electromagnetically Locked Egress Doors – prior to the 2015 edition of the IBC, this section was called Access-Controlled Egress Doors. The title was changed in order to avoid confusion about whether this section was intended to apply to all doors with access control readers (that is not the intent).
- Electromagnetically Locked Egress Doors – beginning with the 2018 edition of the IBC, this section will be called Door Hardware Release of Electrically Locked Egress Doors to be consistent with the sensor-release section.
NFPA 101 – The Life Safety Code, has slightly different titles for these sections, but the requirements are similar:
- Access-Controlled Egress Doors for electrified locks released by a sensor
- Electrically Controlled Egress Door Assemblies for electrified locks released by door-mounted hardware incorporating a switch
According to the IBC and NFPA 101, an electrified lock released by a sensor mounted on the egress side to detect an approaching occupant must also be unlocked in the direction of egress by the following:
- Loss of power to the sensor
- Loss of power to the lock or locking system
- Activation of the building fire alarm or automatic sprinkler system, where provided, and the door must remain unlocked until the fire protection system has been reset.
- A manual unlocking device (typically a push button) that is located 40 to 48 inches above the floor and within 5 feet of the door. Ready access must be provided to the push button, and the button 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.
The model codes include the following requirements for an electrified lock released by door-mounted hardware that incorporates a built-in switch:
- The hardware mounted on the door must have an obvious method of operation and must be readily operated with one hand and under all lighting conditions.
- Operation of the hardware must directly interrupt the power to the lock, and the door must unlock immediately.
- The door must also unlock upon loss of power to the locking system.
- If panic hardware is required, operation of the panic hardware or fire exit hardware must release the lock.
- Note that this section does not require the door to unlock upon activation of the fire protection system.
Both of these types of electrified locks – those released by a sensor and those released by door-mounted hardware, must be allowed by the use group or occupancy classification; they are not allowed in every type of building. Refer to the applicable code for the list of occupancy types where these locks are acceptable, along with specific requirements regarding emergency lighting and the activation of manual fire alarm boxes. Some editions of the model codes also require the door locking system units to be listed in accordance with UL 294 – Standard for Access Control System Units.
There has been a lot of confusion about where and when to apply these code sections. Note that they only apply to electrified locks released by a sensor, and electrified locks released by door-mounted hardware. Electromechanical locks that allow free and immediate egress by turning a lever or pushing the touchpad of the panic hardware, are not required to comply with these two model code sections. There are additional sections that apply to delayed egress locks, controlled egress locks in health care facilities, stairwell reentry, and fail-safe locks on elevator lobby doors (NFPA 101 only).
States and local jurisdictions may modify the model codes, so it’s important to check the codes that have been adopted in a project’s location to verify whether these requirements apply. The Authority Having Jurisdiction (the AHJ) can be consulted for more information.