Magnetic Door Holders
Fire Alarm-Integrated Door Release

What Is a Magnetic Door Holder?

A magnetic door holder is an electromagnetic device that holds a fire-rated door in the open position during normal building operations and releases it automatically upon fire alarm activation, allowing the door’s self-closer to shut the door and restore the fire-rated barrier. The device consists of two parts: an electromagnet mounted to the wall or floor and a steel strike plate mounted to the door. When energized, the electromagnet holds the door open against the tension of the door closer. When power is removed — either by fire alarm activation or power failure — the magnet releases and the closer pulls the door shut NFPA 80, §5.2.8.

Magnetic door holders solve a persistent facility management challenge: fire-rated doors in corridors, stairwells, and smoke compartment boundaries must be self-closing and self-latching per NFPA 80, but occupants prop them open with wedges, trash cans, or tie-backs because the heavy closers impede daily traffic. Door holders provide a code-compliant way to keep doors open when there is no fire and ensure they close automatically when one is detected.

How They Connect to the Fire Alarm System

Magnetic door holders interface with the fire alarm system in one of two ways:

Direct FACP connection: The holder is wired to a notification appliance circuit (NAC) or a dedicated relay output on the fire alarm control panel. When the panel enters alarm, it de-energizes the circuit, causing all holders on that circuit to release. This is the simplest and most common configuration for buildings with a centralized fire alarm system NFPA 72, §21.8.

Integral smoke detector: Some magnetic door holders include a built-in smoke detector listed to UL 228. The detector monitors the local environment and releases the door when it senses smoke, even before the building-wide alarm activates. These standalone units are useful in buildings without a fire alarm system or where specific doors need earlier release. The integral detector must still be connected to the building fire alarm system if one exists, so the release event is annunciated UL 228.

Fail-safe design: All magnetic door holders are designed to be fail-safe — meaning power loss causes release. If the building loses power or the fire alarm circuit fails, the doors close automatically. This fail-safe behavior is a code requirement, not just a design preference NFPA 80, §5.2.8.1.

Where Are They Required?

Magnetic door holders are not required in the same way that detectors or sprinklers are required. Rather, they are a permitted method for holding open fire doors that would otherwise be required to remain closed:

Corridor fire doors: Doors in fire-rated corridor walls may be held open by listed electromagnetic devices connected to the fire alarm system. Wedges, kickstands, or any other non-listed hold-open device is a code violation NFPA 101, §7.2.1.8.

Smoke barrier doors: Doors in smoke barrier walls (common in healthcare facilities separating smoke compartments) are frequently held open by magnetic holders. Healthcare surveyors from CMS and The Joint Commission pay close attention to these doors.

Stairwell doors: Stairwell doors may be held open if equipped with listed holders and a smoke detection release. However, some AHJs prohibit holding stairwell doors open regardless.

Hazardous area separation doors: Doors separating hazardous areas (boiler rooms, generator rooms, storage rooms) should generally remain closed and are typically not candidates for hold-open devices.

Installation Requirements

Mounting: The electromagnet may be wall-mounted, floor-mounted, or integrated into the door closer assembly. Wall-mounted holders must be positioned to hold the door at the proper angle (typically 90 degrees or greater) without interfering with egress width. The magnet must align precisely with the strike plate — misalignment weakens the hold and allows the door to creep closed.

Holding force: The electromagnet must have sufficient holding force to keep the door open against the spring tension of the closer. Standard holders range from 25 to 80 pounds of holding force. The selected holder must be matched to the closer force.

Wiring: Holders connected to the FACP are typically wired in parallel on a 24 VDC circuit. When the relay de-energizes, all holders on the circuit release simultaneously. The wiring must be supervised per NFPA 72 requirements for notification appliance circuits.

Signage: NFPA 80 requires that fire doors be labeled and that any hold-open device be listed and labeled. The holder’s UL listing mark must be visible.

Inspection, Testing & Maintenance

Both NFPA 72 and NFPA 80 address ITM for magnetic door holders:

Annual functional test: Initiate a fire alarm condition (or trigger the holder’s release circuit) and confirm each door releases from the holder, closes completely, and latches. A door that releases but does not latch fails the test — the closer may need adjustment or replacement NFPA 80, §5.2.4.

Healthcare-specific requirements: In healthcare occupancies, fire door inspections including magnetic holder testing are required annually per NFPA 80 and are a frequent survey focus for CMS and The Joint Commission.

Common Deficiencies

Doors propped with wedges instead of holders: The most common and most dangerous deficiency. A wedged-open fire door will not close during a fire. If the building has no fire alarm system, the door stays open indefinitely. Removing wedges and installing proper holders is a frequent AHJ requirement.

Holder does not release on alarm: Wiring faults, blown fuses, or programming errors can prevent the holder from de-energizing during an alarm. This is caught during annual testing.

Door does not latch after release: The closer is too weak, the latch is misaligned, or the floor has settled. The door must both close and positively latch to maintain its fire rating.

Missing strike plate: The steel plate falls off or is removed during painting, leaving only the electromagnet. Without the plate, the door cannot be held open and the purpose of the holder is defeated.

Holder overridden by occupants: In some facilities, staff tape the strike plate to the magnet, zip-tie the door to the holder, or bypass the release circuit to keep the door from closing during drills. This is a serious code violation.

Practical Inspection Tips

Walk every corridor: During a facility walkthrough, note every fire door and check whether it is self-closing, propped open with a non-listed device, or held open by a listed magnetic holder. Document each one.

Pull-test the magnet: Gently try to pull the door free from the holder. It should require moderate effort. If the door falls free easily, the magnet may be failing or the strike plate may be dirty. Clean both surfaces.

Trigger a local alarm: During annual testing, activate a nearby pull station or detector and confirm the holder releases. Then walk to the door and confirm it has fully closed and latched.

Check the closer: After the holder releases, watch the door close. It should swing closed at a controlled speed and latch without slamming. A door that drifts to within 1 inch but does not latch fails.

References