Electromagnetic and Interlock Devices

Electromagnetic locks are popular on college campuses and in schools. It’s important to be aware of the 2009 edition of the IBC and NFPA 101 that introduced new sections addressing electromagnetic locks — “Electromagnetically Locked Egress Doors” (IBC) and “Electrically Controlled Egress Door Assemblies” (NFPA 101). These new sections allow electromagnetic locks to be released with a door-mounted release device, such as a request-to-exit (RX) switch in a latchset, panic hardware or by a touch-sense bar. The lock must also release upon loss of power to the switch in the door-mounted hardware. There is no requirement in this section for the door to automatically release upon fire alarm, although the code official may prefer that added safety feature.

Prior to the 2009 editions, only one section of each publication addressed electromagnetic locks: “Access Controlled Egress Doors.” This sec
tion still exists, so this is a second viable option for doors with electromagnetic locks. This would typically be applied to electromagnetic locks controlled by a motion sensor and also requires an emergency pushbutton that unlocks the door for 30 seconds — independent of the access control system, automatic unlock upon fire alarm and unlock upon power failure.

Both sets of requirements apply to specific occupancy types, so the use of electromagnetic locks in either configuration is restricted to those occupancies. When electromagnetic locks are specified, keep in mind the requirement for 80 inches of headroom from the floor to the projecting hardware. There is an exception that allows 78 inches to the closer arm or overhead stop, but this exception does not specifically address electromagnetic locks that project below the 80-inch point.

Where there is a need to restrict the flow of traffic, such as a cleanroom in a university laboratory, interlocks are often specified. These are typically set up as a vestibule with two door openings that control access and egress by allowing only one door to be opened at a time. When one door is opened and someone enters the vestibule or interlock, the second door may not be opened until the first door comes to a close.

Interlocks are not addressed in the IBC or NFPA 101, so each case must be addressed with the code official for that jurisdiction. Emergency devices, such as an alarmed pushbutton, should be specified inside the room and inside the vestibule to provide a means of emergency egress. An override from the access side should be provided as well, to allow access in an emergency.

Rooftops and Wrapping Up

Many schools incorporate enclosed courtyards to increase the natural light to spaces within the building’s interior and it is becoming more common to see university roof decks used as assembly space. If these spaces are accessible to building occupants, free egress must be provided — often back into the building. From a security perspective this can sometimes be a problem but any methods implemented to restrict egress from the courtyard or roof would require approval from the code official.

If a roof is used only for mechanical equipment and the door is locked from the stairs side, free egress from the roof may not be required depending on the specific code that has been adopted for the project’s jurisdiction. If a courtyard is only used for light and green space and is never occupied by anyone other than landscaping or service personnel, consideration may be given for the egress from this space as well.

In closing, a lack of understanding of code requirements for accessibility, fire resistance and egress can result in noncompliant door openings and liability for the security integrator, supplier and institution. A working knowledge of the codes pertaining to door openings should be included in the education of each person involved in this work to avoid pitfalls. If noncompliant hardware is supplied to a school, the code official may require replacement of the new material with appropriate products. If the problem is not identified during the code official’s inspection, a situation could arise that results in lack of access or egress, injury or even fatalities.

Lori Greene, AHC/CDC, CCPR, FDAI is Ingersoll Rand Security Technologies’ Manager-Codes and Resources. Read her security hardware blog at idighardware.com or contact her at [email protected].

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Applying ADA Standards to Access Control

The two national standards used for accessibility are the 2010 Americans with Disabilities Act (ADA) Standards for Accessible Design and International Code Council (ICC) A117.1 – Accessible and Usable Buildings and Facilities, which is referenced by the International Building Code (IBC). These accessibility standards require operating hardware to be mounted within the allowable range of 34 inches to 48 inches above the floor.

Hardware must be operable without tight grasping, pinching, or twisting of the wrist and door pulls must allow the user to insert their hand behind the pull so tight grasping is not necessary. The bottom surface of the push side of the door, from the floor or ground to 10 inches above, must be flush and smooth with no protrusions. The required clear opening width must be maintained so any protrusions above the 10-inch height must be carefully considered.

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Field Modification of Fire Doors

If new access control hardware is installed on a fi re door assembly, the requirements of NFPA 80 — “Standard for Fire Doors and Other Opening Protectives” — must be followed. There are strict limitations within NFPA 80 for field modification of fi re doors, including a limitation of 1-inch diameter holes for new hardware (except cylinder holes, which may be of any diameter).

If the preparations for new hardware exceed the limits set by NFPA 80, the door and frame may need to be relabeled by the listing agency, which can be very costly. Any modifications must also maintain the required self-closing and positive-latching functions. A violation example of this would be where fire exit hardware has been removed and electromagnetic locks installed — leaving fire doors with no positive latch and affecting the assembly’s ability to restrict the spread of fire.

 

 

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