How To Install Electromagnetic Locks For Life Safety

April 2, 2018
Because an improperly installed EML can slow or even prevent egress in the event of a fire, a quality, code-compliant installation is essential

The need for mechanical locks and electrified locking hardware for general security is huge, especially in crime ridden urban centers. High rise tenant suites of various kinds, common office buildings, government facilities and libraries, all are of major concern where it comes to the proper installation of electromagnetic locks (EMLs). This is of crucial importance because an improperly installed EML can slow or even prevent egress at the most inopportune moment, such as when there’s a life-threatening fire. Hence, because of past experiences, a quality, “legal” installation requires the strict observance of all applicable fire codes as specified by the National Fire Protection Association of Quincy, Mass.

“Most pitfalls are encountered when one attempts to apply ‘security’ measures to fire and life safety related elements of a building, usually at the exits. ‘Delayed Release Exiting’ is an example of the code writer’s effort to give acceptable consideration to security concerns,” says Michael Minieri, principal security consultant and SME (Subject Matter Expert) with Minieri Associates of Orlando, Florida. “History is full of cases where fire fatalities were the direct result of occupants being unable to use an exit.”

For example, in Section of NFPA 101, 2009 Edition, entitled ‘Delayed-Egress Locking Systems, fire code allows for a 15-second delay before release with the idea of apprehending a criminal in the act of fleeing the scene of a crime -- 30 seconds with approval of the AHJ (Authority Having Jurisdiction). An AHJ can be a city building inspector, village fire official, even an insurance company, to name only a few.

Nobody in the security business would knowingly jeopardize the lives of those who use the access control hardware we install. Deaths and injuries do, however, happen and most of the time it’s because of issues that relate to a timely exit which in turn is often due to equipment failure due to misapplication. Perhaps the most important aspect of what we do at the perimeter (exit discharge) door is related to having a fairly good knowledge of local and statewide fire codes. Unfortunately, those who do not have a working knowledge of these codes can negatively impact the ability of a building’s occupants to survive a raging fire. Perhaps this article will help save a life, but not without your help.

The National Fire Protection Association (NFPA), Underwriters Laboratory (UL), Factory Mutual (FM) and other third-party, code-making organizations perform an enormous service by studying and analyzing fire tragedies in order to make improvements to what we do and do not do in order to preserve lives. They then publish these findings from lessons learned in the form of relevant fire codes for everyone to use. The work they do complements the work you ultimately do.

While chances are you already have had the pleasure of meeting at least one or two maglocks in your career, it goes without saying that there may be those among us who have not. To be sure that everyone starts at the same place, let’s review what EMLs are, how they operate, and why fire codes are an important part of the installation process.

An EML is an electrified locking device designed to prevent entry during those times when a door is unused by the authorized occupants of a building. It uses electricity and magnetism to prevent someone outside the structure from opening the door without a proper “credential.” In this case an acceptable “credential” can be a PIN (Personal Identification Number) with a keypad, an access card in conjunction with a reader, an RFID (Radio Frequency Identification) credential, or a biometric identification system.  

The EML itself most often sits atop the door opposite the hinge. The main lock body usually mounts to the stationary door frame and the “armature”-- in the form of a flat metal plate--fastens to the opposing surface of a movable door.

EMLs designed for the point of exit discharge (see definition below) are usually capable of a holding power of 1200 pounds. Indoor models, which are used primarily to control foot traffic, typically produce a holding power of 600 pounds.

Note: The definition of ‘Exit Discharge’ is “That portion of a means of egress between the termination of an exit and a public way” (Section 3.3.77, NFPA 101, Life Safety Code, 2009 Edition, as well as Section 3.3.72, NFPA 101, 2006 Edition).

There are two basic types of EMLs in use. The most common requires the use of a manual or automatic means of activation when egress is required. According to NFPA, you cannot use a special key or any other special method of egress. The second type of EML uses a built-in pressure sensor to “sense” when someone wants to exit. With this one, as well as the use of panic bar/paddle hardware, the door is clearly labeled in such a manner that an occupant knows to press to leave in an emergency. In this case the EML is required to release within 3 seconds when a minimum of 15 pounds is applied to the door from the inside (Section, NFPA 101, 2009 Edition).

How to Assure Timely Egress

Perhaps a better title for this section would be, “How to Install an EML to Fire Code.” If you’re going to install EMLs, you must know fire code in order to do so. Now, on the other hand, if the extent of your exposure to an EML is at the invitation of an EC (Electrical Contractor), EE (Electrical Engineer), or an Architect, then all compliance issues should already have been considered. But make no mistake about it, in the finale--in a court of law--responsibility for fire code compliance rests with you, the installer.

There is a rhyme and a reason to how EMLs are engineered and installed. It begins with knowing what fire code says about new or existing construction and the hardware necessary to accompany any EMLs you install. For example, everything you need to know about what NFPA requires on the inside of an exit discharge door can be found in Section of NFPA 101, 2009 Edition. We’ll discuss the basics behind these code requirements so you have an idea as to what’s expected.

Because this type of installation does not utilize a typical mechanical lock which provides free egress from inside a facility, and because the EML itself is under the direct control of some type of EAC (Electronic Access Control) system, the method used to exit must be instinctive so it’s easy for someone to understand. This process must comply with Section of NAPA 101, which says, “Locks, if provided, shall not require the use of a key, a tool, or special knowledge or effort for operation from the egress side.”

Secondly, there’s the matter of hindering the egress/exit process because of the installation of an EML and other equipment that goes with it. In this regard, Section 7.1.9, entitled Impediments to Egress, NFPA 101, 2009 Edition,.says, “Any device or alarm installed to restrict the improper use of a means of egress shall be designed and installed so that it cannot, even in case of failure, impede or prevent emergency use of such means of egress, unless otherwise provided in and Chapters 18, 19, 22, and 23.”

Third, there are several devices needed on an exit discharge door when installing an EML. One is an “egress motion detector” and the other is a “manual means of egress,” such as a push button, a panic bar across the door, or a paddle, also installed on the inside of the door. The height of the latter must be no less than 30 inches above finished floor and no more than 48 inches in existing construction--34 and 48 inches respectively in new construction.

The manual means of egress must be positioned no less than 34 inches and no higher than 48 inches above the finished floor in order to comply with Section, NFPA 101, 2009. This specific code reference also assures that your installation meets the requirements set forth with the Federal ADA (Americans with Disabilities Act).

Either one must be equipped with the necessary switching and/or electronics to make egress happen at the door. The idea is that the button or bar will mechanically release the door if the egress motion fails to do so.

Another means of egress is through a REX (Request to Exit) connection, which is commonly used with a card reader or keypad inside the point of exit discharge. “’Request to Exit’ (aka “REX”) are usually considered when attempting to avoid providing a conventional panic bar. Considering the requirement for free egress no matter the circumstances, those concerned with ‘security’ should accept that the use of access control for ‘reading out’ are essentially voluntary. The fire codes allow required exit doors to be secure against entry from the outside,” says Minieri.

This device, which often is used to record users that exit the structure, electrically attaches to an access control door controller or the main host computer. Keep in mind that REX devices--the REX function itself--is not the same thing as the egress function defined in NFPA 101. Where the REX function is optional, providing a ready means of egress is mandatory.

EML Wiring Considerations

Operating power that sustains an EML must be routed through a set of NC (Normally Closed) contacts inside the egress motion as well as the manual release button and panic bar/paddle. When the egress motion or panic hardware is activated, power is severed to the EML locally at the door. Without power, the EML cannot continue to maintain the door in its secure condition, thus allowing the individual requesting egress to exit the building at the point of exit discharge.

Power for your EMLs is also an important issue on several fronts. First, you must size the power supply you use so it not only provides the necessary power to operate one or more EMLs simultaneously, but you also must assure that its power capacity is at least 20 percent higher than the dead-on current requirements of all the EMLs combined. Second, you must calculate the correct size of the metallic cable that carries power to each EML. You also must assure that all the EMLs in the building(s) you’re working in release the doors when there’s a fire alarm condition in progress.

This last requirement brings us to the matter of interconnecting these EMLs with a local, structural fire alarm system when there’s one in the building. Here’s what Section of NFPA 101, 2009 Edition, says about it, “Activation of the building fire-protective signaling system, if provided, shall automatically unlock the doors in the direction of egress, and the doors shall remain unlocked until the fire-protective signaling system has been manually reset.”

Minieri points out that the code requires that occupants be able to exit without the need for ‘special knowledge’ (i.e. pin code) or objects (i.e. card). He says, “For security purposes, the code does provide circumstances to allow of delay or 15 or 30 seconds from activation of the exit device (i.e. panic bar). This time is for a security response which may simply be investigation via CCTV. The most frequent application is probably the retail environment as an anti-shoplifting measure. Kits are readily available and properly ‘listed” for this purpose.’”

The interconnection between EMLs and the manual fire pulls inside a building, also referred to as ‘manual fire alarm boxes’ in NFPA fire code, is different in Section than previous ones. “The activation of manual fire alarm boxes that activate the building fire protective signaling system specified in shall not be required to unlock the doors.” We find the answer to ‘why’ in the opposing annex under the same section reference: “It is not the intent to require doors that restrict access but comply with to comply with the access controlled egress door provisions of” (Section A., NFPA 101, 2009 Edition).

Another issue that you must be aware of is the presence of automatic fire protection. According to Section, “Activation of the building automatic sprinkler or fire detection system, if provided, shall automatically unlock the doors in the direction of egress, and the doors shall remain unlocked until the fire-protective signaling system has been manually reset.”

The fact of the matter is, you will not have to worry about meeting this requirement because you will contact the fire alarm company of record to make all the necessary connections and programming changes so their fire alarm system meets fire code with respect to your EML and all the egress releasing devices you install. You will have to assist them, but the fire alarm system is not your direct responsibility. But it is your responsibility to know when interconnection is required.