Fail-Safe vs. Fail-Secure
Door Hardware That Saves Lives
When the power goes out, does your door lock or unlock? The answer depends on whether the hardware is fail-safe or fail-secure — and getting it wrong can trap people in a fire or leave your building wide open.
The Question That Could Save a Life
Imagine a hospital at 2 AM. The power goes out. Every electrified door in the building is about to do one of two things: lock or unlock. For a patient trying to escape a fire in a smoke-filled corridor, the answer to that question is the difference between life and death.
That's why understanding fail-safe vs. fail-secure hardware isn't just an academic exercise — it's a fundamental life safety concept that every facility manager, safety professional, and contractor needs to understand.
The Core Difference
Fail-Safe
Power OFF = Door UNLOCKED
When power is removed (outage, fire alarm, emergency), the door unlocks automatically. Power must be continuously applied to keep the door locked. Think: “safe for people to escape.”
Fail-Secure
Power OFF = Door LOCKED
When power is removed, the door remains locked on the secure side (outside). Power must be applied to unlock. Think: “secure against unauthorized entry.”
Critical clarification: These terms describe the behavior of the secure side (key side / outside) of the door — not the egress side. In almost all configurations, the egress side always allows free exit regardless of power state. A person on the inside can always get out NFPA 101, §7.2.1.
The Most Common Misconception
Many people assume that all egress doors must use fail-safe hardware. This is not correct. The confusion comes from conflating two different things:
Controlling Ingress (Entry)
Most access-controlled doors restrict who can enter while allowing anyone to exit freely. The lock on the outside (card reader side) can be fail-secure — it stays locked during outages, keeping the building secure. The inside always has free egress via lever or push bar.
Controlling Egress (Exit)
When electrified hardware affects the ability to exit, fail-safe is mandatory. The door must unlock on the egress side when power is lost so people can escape. This is non-negotiable for life safety.
In practice, fail-secure is far more common than fail-safe for standard access control. Think about it: if your office entrance used fail-safe hardware, every power outage would leave your front door unlocked — a security nightmare.
Where Each Type Is Required
🔓 Fail-Safe Required (egress is affected)
Electromagnetic locks (mag locks)
The magnet holds the door closed. Power loss must release it for egress.
Delayed egress locks
The 15/30-second delay system must release on fire alarm or power loss.
Controlled egress (healthcare/behavioral)
Locked psych units or dementia wings must unlock when fire alarm activates or power is lost.
Elevator lobby locks
Must release on fire alarm for elevator recall and firefighter access.
Stairwell reentry locks
Interior stairwell doors must allow re-entry to floors when locked. Fail-safe allows remote unlock during emergencies.
🔒 Fail-Secure Typical (ingress controlled, egress always free)
Card reader access doors (offices, hospitals, schools)
Outside locked by default, badge to enter. Inside lever/push bar always works for exit.
Electric strikes on standard doors
Strike holds latch engaged until access is granted. Free egress via inside lever.
Server rooms and restricted areas
Must remain locked during power outages for security. Egress via panic hardware inside.
Exterior entrance doors
Cannot afford to unlock during every power outage. Badge or key for entry, free exit.
The Fire Door Rule
Electric strikes on fire-rated doors MUST be fail-secure
This is a code requirement that catches many people off guard. Electric strikes installed on fire door assemblies must be fail-secure and listed to UL 10C or NFPA 252. Fail-safe strikes cannot be used on fire doors because the door must remain positively latched to maintain its fire rating during a power loss NFPA 80, §6.4.4.
Think about it: in a fire, the power may go out. If the electric strike were fail-safe, the fire door would be unlatched — defeating its entire purpose as a fire barrier. The door must stay latched and closed to contain fire and smoke.
The Egress Non-Negotiables
Regardless of whether hardware is fail-safe or fail-secure, NFPA 101 and IBC require these egress fundamentals for every door in the means of egress:
One motion to unlatch
A single operation (turn lever, push bar) must unlatch the door for exit. No two-step processes.
NFPA 101, §7.2.1.5.2No special knowledge
No key, tool, code, or special training required to exit. Any person must be able to operate the hardware.
NFPA 101, §7.2.1.5.2No tight grasping
Door hardware must be operable without tight grasping, pinching, or twisting of the wrist (ADA compliant).
NFPA 101, §7.2.1.5.10Proper mounting height
Release hardware must be 34–48 inches above the floor (with limited exceptions for childcare, etc.).
NFPA 101, §7.2.1.5.10Healthcare Spotlight: Controlled Egress
Healthcare facilities have a unique challenge: some patients (dementia, psychiatric, pediatric) must be prevented from leaving unsupervised, but the door must still allow escape during a fire. This is the controlled egress arrangement NFPA 101, §18.2.2.2.5.
Quick Reference Table
This article was inspired by an excellent deep-dive from I Dig Hardware by Lori Greene — one of the best resources on door hardware compliance. Shared with us by Donald Bell, a life safety professional who keeps his team sharp. Thanks, Donald.
References
1. NFPA 101 (2021): Life Safety Code, Chapter 7 — Means of Egress.
2. NFPA 80: Standard for Fire Doors and Other Opening Protectives.
3. IBC (2024): International Building Code, Chapter 10 — Means of Egress.
4. UL 10C: Standard for Positive Pressure Fire Tests of Door Assemblies.
5. Lori Greene, “FAQs About Fail-Safe and Fail-Secure”, I Dig Hardware, October 2022. Shared by Donald Bell.
Was this article helpful?
Rate this article to help us improve
Discussion (2)
Great breakdown of the technical details. The NFPA 25 maintenance table is exactly what I needed for my ITM schedule.
Really clear explanation. Would love to see a companion video walkthrough of the inspection process.