Electromagnetic Locks: Where, When & Why

Oct. 2, 2017
Know the latest code requirements for maglocks on means of egress and other doors

Proper design specification and installation of electrical locking devices is a serious business. Whether you are inexperienced or have been doing it for years, it still requires diligence and in-service training or self study.

The Locksmith Ledger endeavors to offer resources for our readers in this regard. Other publications (not too many) and manufacturers (several of the good ones) also provide resources on their webpages as well as provide classroom training.

When I noted that some code changes had been made and more are proposed that affect the installation of electromagnetic locks, I felt compelled to use the opportunity to learn more, and share with Locksmith Ledger readers.

The hope is this article will whet your appetite to continue your studies into the subject and you put what you learn to practical use.

When I told a friend who is a locksmith of my plans for this article he commented I better be sure to mention at the end of the article to “check with the AHJ.” I said, no I would emphasize it at the beginning of the article, since the Authority Having Jurisdiction’s approval is the most critical factor in the process.

He also mentioned details on some of his past jobs and recent job bids, and it further convinced me this would be a worthwhile topic to discuss.

As new uses for electromagnetic locks are devised and shortcomings in system designs are exposed, the code writers have endeavored to update their rules to best reflect what is allowable and what defines best practices.

Saying you want to do a good job is lip service unless you back it up by remaining up to date with the codes, and maintaining a professional level of workmanship standards.

All building codes are related to the occupancy type which refers to the categorizing of structures based on their usage and are primarily used for building and fire code enforcement.

The occupant load is defined by IBC as “the number of persons for which the means of egress of a building or portion thereof is designed.” It is defined by NFPA101 as the total number of persons that might occupy a building or portion thereof at any one time.

Also note that there are few life safety requirements for how you control entry through an opening, they address how you control egress.

We’re not discussing delayed egress this time, but we frequently offer this topic and searching the Locksmith Ledger should yield many articles on the subject.

Electromagnetic locks are typically used for door access control, but also are used for main entrances to buildings and a variety of specialized applications in schools, healthcare, corrections, banking and corporations. They are used in buildings (interior) and on gates (exterior).

Electromagnetic locks, unlike mechanical locks, do not have an integral means of unlocking them. This is also true for electrically actuated bolts. This means they are potentially dangerous since unless the system they are used with is properly designed the locking device represents an unacceptably high life safety hazard.

Means of Egress

An important term used in door control and life safety is means of egress, defined as a continuous and unobstructed path of vertical and horizontal egress travel from any occupied portion of a building or structure to a public way.

A means of egress consists of three separate and distinct parts:

The exit access: That portion of a means of egress system that leads from any occupied portion of a building or structure to an exit. (ie: everything from the furthest point in an occupied room to the corridor that provides access to the egress stairs)

The exit: That portion of a means of egress system, which is separated from other interior spaces of a building or structure by fire-resistance-rated construction and opening protective as required to provide a protected path of egress travel between the exit access and the exit discharge. Exits include vertical exits, exterior exit doors at ground level, exit enclosures, exit passageways, exterior exit stairs, exterior exit ramps and horizontal exits, but do not include access stairs, aisles, exit access doors opening to corridors, or corridors. (ie: everything from the exit stairs to the doors that lead to the exterior)

The exit discharge: That portion of a means of egress system between the termination of an exit and a public way (the doors that lead into the public way.

The title “Access-Controlled Egress Doors” appears in NFPA 101–Life Safety Code and past editions of the International Building Code (IBC). The corresponding section in NFPA 101 is called Access-Controlled Egress Doors, but the two sets of requirements are very similar despite the differing section titles.

These two sections apply to electrically/electromagnetically locked doors, where the lock is released by a sensor detecting an approaching occupant. 

Both the IBC and NFPA 101 also include separate sections that apply to electrically/electromagnetically locked doors that are released by door-mounted hardware incorporating a switch to release the electrified lock. 

Again, electromagnetic locks require a separate release device – a sensor or a switch in the door-mounted hardware. Mag-lock applications are typically released by one of these two types of switches.  In NFPA 101, the section for mag-locks released by a switch in the door-mounted hardware is called Electrically Controlled Egress Door Assemblies.  In the IBC, this section is currently called Electromagnetically Locked Egress Doors, but beginning with the 2018 edition of the IBC, this section will be called Door Hardware Release of Electrically Locked Egress Doors.

Controlling egress for electromagnetic locks used for access control typically fall into one of two categories:

1. Electrified/electromagnetic lock released by a sensor that detects an occupant approaching the door and unlocks the door for egress.

NFPA 101 Section:  Access-Controlled Egress Doors. IBC Section:  Sensor Release of Electromagnetically Locked Egress Doors (prior to the 2015 edition: Access-Controlled Egress Doors)

In addition to unlocking when the sensor detects an approaching occupant, the door must unlock upon:

  • 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 pushbutton) 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.

2. Electrified/electromagnetic lock released by door-mounted hardware that incorporates a switch to immediately release the lock for egress

NFPA 101 Section:  Electrically Controlled Egress Door Assemblies. IBC Section:  Electromagnetically Locked Egress Doors (beginning with the 2018 edition: Door Hardware Release of Electrically Locked Egress Doors)

These sections require the following:

  • 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. 

If all this hasn’t met your minimum daily code requirement, also 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.

About the Author

Tim O'Leary

Tim O'Leary is a security consultant, trainer and technician who has also been writing articles on all areas of locksmithing & physical security for many years.